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Sample records for host epithelial tissue

  1. Computational modeling of epithelial tissues.

    PubMed

    Smallwood, Rod

    2009-01-01

    There is an extensive literature on the computational modeling of epithelial tissues at all levels from subcellular to whole tissue. This review concentrates on behavior at the individual cell to whole tissue level, and particularly on organizational aspects, and provides an indication of where information from other areas, such as the modeling of angiogenesis, is relevant. The skin, and the lining of all of the body cavities (lung, gut, cervix, bladder etc) are epithelial tissues, which in a topological sense are the boundary between inside and outside the body. They are thin sheets of cells (usually of the order of 0.5 mm thick) without extracellular matrix, have a relatively simple structure, and contain few types of cells. They have important barrier, secretory and transport functions, which are essential for the maintenance of life, so homeostasis and wound healing are important aspects of the behavior of epithelial tissues. Carcinomas originate in epithelial tissues.There are essentially two approaches to modeling tissues--to start at the level of the tissue (i.e., a length scale of the order of 1 mm) and develop generalized equations for behavior (a continuum approach); or to start at the level of the cell (i.e., a length scale of the order of 10 µm) and develop tissue behavior as an emergent property of cellular behavior (an individual-based approach). As will be seen, these are not mutually exclusive approaches, and they come in a variety of flavors.

  2. Force transmission in epithelial tissues.

    PubMed

    Vasquez, Claudia G; Martin, Adam C

    2016-03-01

    In epithelial tissues, cells constantly generate and transmit forces between each other. Forces generated by the actomyosin cytoskeleton regulate tissue shape and structure and also provide signals that influence cells' decisions to divide, die, or differentiate. Forces are transmitted across epithelia because cells are mechanically linked through junctional complexes, and forces can propagate through the cell cytoplasm. Here, we review some of the molecular mechanisms responsible for force generation, with a specific focus on the actomyosin cortex and adherens junctions. We then discuss evidence for how these mechanisms promote cell shape changes and force transmission in tissues.

  3. Normal morphogenesis of epithelial tissues and progression of epithelial tumors

    PubMed Central

    Wang, Chun-Chao; Jamal, Leen; Janes, Kevin A.

    2011-01-01

    Epithelial cells organize into various tissue architectures that largely maintain their structure throughout the life of an organism. For decades, the morphogenesis of epithelial tissues has fascinated scientists at the interface of cell, developmental, and molecular biology. Systems biology offers ways to combine knowledge from these disciplines by building integrative models that are quantitative and predictive. Can such models be useful for gaining a deeper understanding of epithelial morphogenesis? Here, we take inventory of some recurring themes in epithelial morphogenesis that systems approaches could strive to capture. Predictive understanding of morphogenesis at the systems level would prove especially valuable for diseases such as cancer, where epithelial tissue architecture is profoundly disrupted. PMID:21898857

  4. Normal morphogenesis of epithelial tissues and progression of epithelial tumors.

    PubMed

    Wang, Chun-Chao; Jamal, Leen; Janes, Kevin A

    2012-01-01

    Epithelial cells organize into various tissue architectures that largely maintain their structure throughout the life of an organism. For decades, the morphogenesis of epithelial tissues has fascinated scientists at the interface of cell, developmental, and molecular biology. Systems biology offers ways to combine knowledge from these disciplines by building integrative models that are quantitative and predictive. Can such models be useful for gaining a deeper understanding of epithelial morphogenesis? Here, we take inventory of some recurring themes in epithelial morphogenesis that systems approaches could strive to capture. Predictive understanding of morphogenesis at the systems level would prove especially valuable for diseases such as cancer, where epithelial tissue architecture is profoundly disrupted.

  5. Undulation Instability of Epithelial Tissues

    NASA Astrophysics Data System (ADS)

    Basan, Markus; Joanny, Jean-François; Prost, Jacques; Risler, Thomas

    2011-04-01

    Treating the epithelium as an incompressible fluid adjacent to a viscoelastic stroma, we find a novel hydrodynamic instability that leads to the formation of protrusions of the epithelium into the stroma. This instability is a candidate for epithelial fingering observed in vivo. It occurs for sufficiently large viscosity, cell-division rate and thickness of the dividing region in the epithelium. Our work provides physical insight into a potential mechanism by which interfaces between epithelia and stromas undulate and potentially by which tissue dysplasia leads to cancerous invasion.

  6. Soft tissue and epithelial models.

    PubMed

    Jansen, J A; den Braber, E T; Walboomers, X F; de Ruijter, J E

    1999-06-01

    The applicability of a biomaterial for the manufacturing of oral implants is determined by its physicochemical and geometric surface properties. Research, therefore, is concerned with the cellular reactions that occur when an implant material comes into contact with body tissues. For permucosal oral implants, this involves both the reaction of bone and gingival cells. In vitro cell culturing--including the use of various analytical techniques like light microscopy, scanning and transmission electron microscopy, confocal laser scanning microscopy, and digital image analysis--is a good tool whereby investigators can obtain more insight into the relevant components of implant-tissue adhesion. In the current overview, the role of cell models in oral implant research is discussed, specifically with reference to responses of epithelial cells and fibroblasts.

  7. Three-Dimensional Human Bronchial-Tracheal Epithelial Tissue-Like Assemblies (TLAs) as Hosts for Severe Acute Respiratory Syndrome (SARS)-CoV Infection

    NASA Technical Reports Server (NTRS)

    Suderman, M. T.; McCarthy, M.; Mossell, E.; Watts, D. M.; Peters, C. J.; Shope, R.; Goodwin, T. J.

    2006-01-01

    A three-dimensional (3-D) tissue-like assembly (TLA) of human bronchial-tracheal mesenchymal (HBTC) cells with an overlay of human bronchial epithelial (BEAS-2B) cells was constructed using a NASA Bioreactor to survey the infectivity of SARS-CoV. This TLA was inoculated with a low passage number Urbani strain of SARS-CoV. At selected intervals over a 10-day period, media and cell aliquots of the 3-D TLA were harvested for viral titer assay and for light and electron microscopy examination. All viral titer assays were negative in both BEAS-2B two-dimensional monolayer and TLA. Light microscopy immunohistochemistry demonstrated antigen-antibody reactivity with anti-SARS-CoV polyclonal antibody to spike and nuclear proteins on cell membranes and cytoplasm. Coronavirus Group 2 cross-reactivity was demonstrated by positive reaction to anti-FIPV 1 and anti-FIPV 1 and 2 antibodies. TLA examination by transmission electron microscopy indicated increasing cytoplasmic vacuolation with numerous electron-dense bodies measuring 45 to 270 nm from days 4 through 10. There was no evidence of membrane blebbing, membrane duplication, or fragmentation of organelles in the TLAs. However, progressive disruption of endoplasmic reticulum was observed throughout the cells. Antibody response to SARS-CoV specific spike and nucleocapsid glycoproteins, cross-reactivity with FIPV antibodies, and the cytoplasmic pathology suggests this HBTE TLA model is permissive to SARS-CoV infection.

  8. Segmentation and Quantitative Analysis of Epithelial Tissues.

    PubMed

    Aigouy, Benoit; Umetsu, Daiki; Eaton, Suzanne

    2016-01-01

    Epithelia are tissues that regulate exchanges with the environment. They are very dynamic and can acquire virtually any shape; at the cellular level, they are composed of cells tightly connected by junctions. Most often epithelia are amenable to live imaging; however, the large number of cells composing an epithelium and the absence of informatics tools dedicated to epithelial analysis largely prevented tissue scale studies. Here we present Tissue Analyzer, a free tool that can be used to segment and analyze epithelial cells and monitor tissue dynamics.

  9. Host epithelial geometry regulates breast cancer cell invasiveness.

    PubMed

    Boghaert, Eline; Gleghorn, Jason P; Lee, KangAe; Gjorevski, Nikolce; Radisky, Derek C; Nelson, Celeste M

    2012-11-27

    Breast tumor development is regulated in part by cues from the local microenvironment, including interactions with neighboring nontumor cells as well as the ECM. Studies using homogeneous populations of breast cancer cell lines cultured in 3D ECM have shown that increased ECM stiffness stimulates tumor cell invasion. However, at early stages of breast cancer development, malignant cells are surrounded by normal epithelial cells, which have been shown to exert a tumor-suppressive effect on cocultured cancer cells. Here we explored how the biophysical characteristics of the host microenvironment affect the proliferative and invasive tumor phenotype of the earliest stages of tumor development, by using a 3D microfabrication-based approach to engineer ducts composed of normal mammary epithelial cells that contained a single tumor cell. We found that the phenotype of the tumor cell was dictated by its position in the duct: proliferation and invasion were enhanced at the ends and blocked when the tumor cell was located elsewhere within the tissue. Regions of invasion correlated with high endogenous mechanical stress, as shown by finite element modeling and bead displacement experiments, and modulating the contractility of the host epithelium controlled the subsequent invasion of tumor cells. Combining microcomputed tomographic analysis with finite element modeling suggested that predicted regions of high mechanical stress correspond to regions of tumor formation in vivo. This work suggests that the mechanical tone of nontumorigenic host epithelium directs the phenotype of tumor cells and provides additional insight into the instructive role of the mechanical tumor microenvironment.

  10. Studying cytokinesis in Drosophila epithelial tissues.

    PubMed

    Pinheiro, D; Bellaïche, Y

    2017-01-01

    Epithelial tissue cohesiveness is ensured through cell-cell junctions that maintain both adhesion and mechanical coupling between neighboring cells. During development, epithelial tissues undergo intensive cell proliferation. Cell division, and particularly cytokinesis, is coupled to the formation of new adhesive contacts, thereby preserving tissue integrity and propagating cell polarity. Remarkably, the geometry of the new interfaces is determined by the combined action of the dividing cell and its neighbors. To further understand the interplay between the dividing cell and its neighbors, as well as the role of cell division for tissue morphogenesis, it is important to analyze cytokinesis in vivo. Here we present methods to perform live imaging of cell division in Drosophila epithelial tissues and discuss some aspects of image processing and analysis.

  11. Mechanics of epithelial tissue homeostasis and morphogenesis.

    PubMed

    Guillot, Charlène; Lecuit, Thomas

    2013-06-07

    Epithelia are robust tissues that support the structure of embryos and organs and serve as effective barriers against pathogens. Epithelia also chemically separate different physiological environments. These vital functions require tight association between cells through the assembly of junctions that mechanically stabilize the tissue. Remarkably, epithelia are also dynamic and can display a fluid behavior. Cells continuously die or divide, thereby allowing functional tissue homeostasis. Epithelial cells can change shape or intercalate as tissues deform during morphogenesis. We review the mechanical basis of tissue robustness and fluidity, with an emphasis on the pivotal role of junction dynamics. Tissue fluidity emerges from local active stresses acting at cell interfaces and allows the maintenance of epithelial organization during morphogenesis and tissue renewal.

  12. Epithelial-mesenchymal transition in tissue repair and fibrosis.

    PubMed

    Stone, Rivka C; Pastar, Irena; Ojeh, Nkemcho; Chen, Vivien; Liu, Sophia; Garzon, Karen I; Tomic-Canic, Marjana

    2016-09-01

    The epithelial-mesenchymal transition (EMT) describes the global process by which stationary epithelial cells undergo phenotypic changes, including the loss of cell-cell adhesion and apical-basal polarity, and acquire mesenchymal characteristics that confer migratory capacity. EMT and its converse, MET (mesenchymal-epithelial transition), are integral stages of many physiologic processes and, as such, are tightly coordinated by a host of molecular regulators. Converging lines of evidence have identified EMT as a component of cutaneous wound healing, during which otherwise stationary keratinocytes (the resident skin epithelial cells) migrate across the wound bed to restore the epidermal barrier. Moreover, EMT plays a role in the development of scarring and fibrosis, as the matrix-producing myofibroblasts arise from cells of the epithelial lineage in response to injury but are pathologically sustained instead of undergoing MET or apoptosis. In this review, we summarize the role of EMT in physiologic repair and pathologic fibrosis of tissues and organs. We conclude that further investigation into the contribution of EMT to the faulty repair of fibrotic wounds might identify components of EMT signaling as common therapeutic targets for impaired healing in many tissues. Graphical Abstract Model for injury-triggered EMT activation in physiologic wound repair (left) and fibrotic wound healing (right).

  13. Adhesion to the host cell surface is sufficient to mediate Listeria monocytogenes entry into epithelial cells.

    PubMed

    Ortega, Fabian E; Rengarajan, Michelle; Chavez, Natalie; Radhakrishnan, Prathima; Gloerich, Martijn; Bianchini, Julie; Siemers, Kathleen; Luckett, William S; Lauer, Peter; Nelson, W James; Theriot, Julie A

    2017-09-06

    An intestinal epithelium is the first physiological barrier breached by the Gram-positive facultative pathogen Listeria monocytogenes during an in vivo infection. L. monocytogenes binds to the epithelial host cell receptor E-cadherin, which mediates a physical link between the bacterium and filamentous actin (F-actin). However, the importance of anchoring the bacterium to F-actin through E-cadherin for bacterial invasion has not been tested directly in epithelial cells. Here, we demonstrate that depleting αE-catenin, which indirectly links E-cadherin to F-actin, did not decrease L. monocytogenes invasion of epithelial cells in tissue culture. Instead, invasion increased due to increased bacterial adhesion to epithelial monolayers with compromised cell-cell junctions. Furthermore, expression of a mutant E-cadherin lacking the intracellular domain was sufficient for efficient L. monocytogenes invasion of epithelial cells. Importantly, direct biotin-mediated binding of bacteria to surface lipids in the plasma membrane of host epithelial cells was sufficient for uptake. Our results indicate that the only requirement for L. monocytogenes invasion of epithelial cells is adhesion to the host cell surface, and that E-cadherin-mediated coupling of the bacterium to F-actin is not required. © 2017 by The American Society for Cell Biology.

  14. Site-specific programming of the host epithelial transcriptome by the gut microbiota.

    PubMed

    Sommer, Felix; Nookaew, Intawat; Sommer, Nina; Fogelstrand, Per; Bäckhed, Fredrik

    2015-03-28

    The intestinal epithelium separates us from the microbiota but also interacts with it and thus affects host immune status and physiology. Previous studies investigated microbiota-induced responses in the gut using intact tissues or unfractionated epithelial cells, thereby limiting conclusions about regional differences in the epithelium. Here, we sought to investigate microbiota-induced transcriptional responses in specific fractions of intestinal epithelial cells. To this end, we used microarray analysis of laser capture microdissection (LCM)-harvested ileal and colonic tip and crypt epithelial fractions from germ-free and conventionally raised mice and from mice during the time course of colonization. We found that about 10% of the host's transcriptome was microbially regulated, mainly including genes annotated with functions in immunity, cell proliferation, and metabolism. The microbial impact on host gene expression was highly site specific, as epithelial responses to the microbiota differed between cell fractions. Specific transcriptional regulators were enriched in each fraction. In general, the gut microbiota induced a more rapid response in the colon than in the ileum. Our study indicates that the microbiota engage different regulatory networks to alter host gene expression in a particular niche. Understanding host-microbiota interactions on a cellular level may facilitate signaling pathways that contribute to health and disease and thus provide new therapeutic strategies.

  15. Autophagy Controls an Intrinsic Host Defense to Bacteria by Promoting Epithelial Cell Survival: A Murine Model

    PubMed Central

    Chang, Sun-Young; Lee, Se-Na; Yang, Jin-Young; Kim, Dong Wook; Yoon, Joo-Heon; Ko, Hyun-Jeong; Ogawa, Michinaga; Sasakawa, Chihiro; Kweon, Mi-Na

    2013-01-01

    Cell death is a critical host response to regulate the fate of bacterial infections, innate immune responses, and ultimately, disease outcome. Shigella spp. invade and colonize gut epithelium in human and nonhuman primates but adult mice are naturally resistant to intra-gastric Shigella infection. In this study, however, we found Shigella could invade the terminal ileum of the mouse small intestine by 1 hour after infection and be rapidly cleared within 24 h. These early phase events occurred shortly after oral infection resulting in epithelial shedding, degranulation of Paneth cells, and cell death in the intestine. During this process, autophagy proceeded without any signs of inflammation. In contrast, blocking autophagy in epithelial cells enhanced host cell death, leading to tissue destruction and to inflammation, suggesting that autophagic flow relieves cellular stress associated with host cell death and inflammation. Herein we propose a new concept of “epithelial barrier turnover” as a general intrinsic host defense mechanism that increases survival of host cells and inhibits inflammation against enteric bacterial infections, which is regulated by autophagy. PMID:24260541

  16. ROCK1-directed basement membrane positioning coordinates epithelial tissue polarity.

    PubMed

    Daley, William P; Gervais, Elise M; Centanni, Samuel W; Gulfo, Kathryn M; Nelson, Deirdre A; Larsen, Melinda

    2012-01-01

    The basement membrane is crucial for epithelial tissue organization and function. However, the mechanisms by which basement membrane is restricted to the basal periphery of epithelial tissues and the basement membrane-mediated signals that regulate coordinated tissue organization are not well defined. Here, we report that Rho kinase (ROCK) controls coordinated tissue organization by restricting basement membrane to the epithelial basal periphery in developing mouse submandibular salivary glands, and that ROCK inhibition results in accumulation of ectopic basement membrane throughout the epithelial compartment. ROCK-regulated restriction of PAR-1b (MARK2) localization in the outer basal epithelial cell layer is required for basement membrane positioning at the tissue periphery. PAR-1b is specifically required for basement membrane deposition, as inhibition of PAR-1b kinase activity prevents basement membrane deposition and disrupts overall tissue organization, and suppression of PAR-1b together with ROCK inhibition prevents interior accumulations of basement membrane. Conversely, ectopic overexpression of wild-type PAR-1b results in ectopic interior basement membrane deposition. Significantly, culture of salivary epithelial cells on exogenous basement membrane rescues epithelial organization in the presence of ROCK1 or PAR-1b inhibition, and this basement membrane-mediated rescue requires functional integrin β1 to maintain epithelial cell-cell adhesions. Taken together, these studies indicate that ROCK1/PAR-1b-dependent regulation of basement membrane placement is required for the coordination of tissue polarity and the elaboration of tissue structure in the developing submandibular salivary gland.

  17. Polarized protein transport and lumen formation during epithelial tissue morphogenesis.

    PubMed

    Blasky, Alex J; Mangan, Anthony; Prekeris, Rytis

    2015-01-01

    One of the major challenges in biology is to explain how complex tissues and organs arise from the collective action of individual polarized cells. The best-studied model of this process is the cross talk between individual epithelial cells during their polarization to form the multicellular epithelial lumen during tissue morphogenesis. Multiple mechanisms of apical lumen formation have been proposed. Some epithelial lumens form from preexisting polarized epithelial structures. However, de novo lumen formation from nonpolarized cells has recently emerged as an important driver of epithelial tissue morphogenesis, especially during the formation of small epithelial tubule networks. In this review, we discuss the latest findings regarding the mechanisms and regulation of de novo lumen formation in vitro and in vivo.

  18. Polarized Protein Transport and Lumen Formation During Epithelial Tissue Morphogenesis

    PubMed Central

    Blasky, Alex J.; Mangan, Anthony; Prekeris, Rytis

    2015-01-01

    One of the major challenges in biology is to explain how complex tissues and organs arise from the collective action of individual polarized cells. The best-studied model of this process is the cross talk between individual epithelial cells during their polarization to form the multicellular epithelial lumen during tissue morphogenesis. Multiple mechanisms of apical lumen formation have been proposed. Some epithelial lumens form from preexisting polarized epithelial structures. However, de novo lumen formation from nonpolarized cells has recently emerged as an important driver of epithelial tissue morphogenesis, especially during the formation of small epithelial tubule networks. In this review, we discuss the latest findings regarding the mechanisms and regulation of de novo lumen formation in vitro and in vivo. PMID:26359775

  19. Know your neighbor: Microbiota and host epithelial cells interact locally to control intestinal function and physiology.

    PubMed

    Sommer, Felix; Bäckhed, Fredrik

    2016-05-01

    Interactions between the host and its associated microbiota differ spatially and the local cross talk determines organ function and physiology. Animals and their organs are not uniform but contain several functional and cellular compartments and gradients. In the intestinal tract, different parts of the gut carry out different functions, tissue structure varies accordingly, epithelial cells are differentially distributed and gradients exist for several physicochemical parameters such as nutrients, pH, or oxygen. Consequently, the microbiota composition also differs along the length of the gut, but also between lumen and mucosa of the same intestinal segment, and even along the crypt-villus axis in the epithelium. Thus, host-microbiota interactions are highly site-specific and the local cross talk determines intestinal function and physiology. Here we review recent advances in our understanding of site-specific host-microbiota interactions and discuss their functional relevance for host physiology.

  20. Crossroads of Wnt and Hippo in epithelial tissues.

    PubMed

    Bernascone, Ilenia; Martin-Belmonte, Fernando

    2013-08-01

    Epithelial tissues undergo constant growth and differentiation during embryonic development and to replace damaged tissue in adult organs. These processes are governed by different signaling pathways that ultimately control the expression of genes associated with cell proliferation, patterning, and death. One essential pathway is Wnt, which controls tubulogenesis in several epithelial organs. Recently, Wnt has been closely linked to other signaling pathways, such as Hippo, that orchestrate proliferation and apoptosis to control organ size. There is evidence that epithelial cell junctions may sequester the transcription factors that act downstream of these signaling pathways, which would represent an important aspect of their functional regulation and their influence on cell behavior. Here, we review the transcriptional control exerted by the Wnt and Hippo signaling pathways during epithelial growth, patterning, and differentiation and recent advances in understanding of the regulation and crosstalk of these pathways in epithelial tissues.

  1. Host Responses in Tissue Repair and Fibrosis

    PubMed Central

    Duffield, Jeremy S.; Lupher, Mark; Thannickal, Victor J.

    2013-01-01

    Myofibroblasts accumulate in the spaces between organ structures and produce extracellular matrix (ECM) proteins, including collagen I. They are the primary “effector” cells in tissue remodeling and fibrosis. Previously, leukocyte progenitors termed fibrocytes and myofibroblasts generated from epithelial cells through epithelial-to-mesenchymal transition (EMT) were considered the primary sources of ECM-producing myofibroblasts in injured tissues. However, genetic fate mapping experiments suggest that mesenchyme-derived cells, known as resident fibroblasts, and pericytes are the primary precursors of scar-forming myofibroblasts, whereas epithelial cells, endothelial cells, and myeloid leukocytes contribute to fibrogenesis predominantly by producing key fibrogenic cytokines and by promoting cell-to-cell communication. Numerous cytokines derived from T cells, macrophages, and other myeloid cell populations are important drivers of myofibroblast differentiation. Monocyte-derived cell populations are key regulators of the fibrotic process: They act as a brake on the processes driving fibrogenesis, and they dismantle and degrade established fibrosis. We discuss the origins, modes of activation, and fate of myofibroblasts in various important fibrotic diseases and describe how manipulation of macrophage activation could help ameliorate fibrosis. PMID:23092186

  2. IFN-λ determines the intestinal epithelial antiviral host defense

    PubMed Central

    Pott, Johanna; Mahlakõiv, Tanel; Mordstein, Markus; Duerr, Claudia U.; Michiels, Thomas; Stockinger, Silvia; Staeheli, Peter; Hornef, Mathias W.

    2011-01-01

    Type I and type III IFNs bind to different cell-surface receptors but induce identical signal transduction pathways, leading to the expression of antiviral host effector molecules. Despite the fact that type III IFN (IFN-λ) has been shown to predominantly act on mucosal organs, in vivo infection studies have failed to attribute a specific, nonredundant function. Instead, a predominant role of type I IFN was observed, which was explained by the ubiquitous expression of the type I IFN receptor. Here we comparatively analyzed the role of functional IFN-λ and type I IFN receptor signaling in the innate immune response to intestinal rotavirus infection in vivo, and determined viral replication and antiviral gene expression on the cellular level. We observed that both suckling and adult mice lacking functional receptors for IFN-λ were impaired in the control of oral rotavirus infection, whereas animals lacking functional receptors for type I IFN were similar to wild-type mice. Using Mx1 protein accumulation as marker for IFN responsiveness of individual cells, we demonstrate that intestinal epithelial cells, which are the prime target cells of rotavirus, strongly responded to IFN-λ but only marginally to type I IFN in vivo. Systemic treatment of suckling mice with IFN-λ repressed rotavirus replication in the gut, whereas treatment with type I IFN was not effective. These results are unique in identifying a critical role of IFN-λ in the epithelial antiviral host defense. PMID:21518880

  3. Heterogeneity and stochastic growth regulation of biliary epithelial cells dictate dynamic epithelial tissue remodeling.

    PubMed

    Kamimoto, Kenji; Kaneko, Kota; Kok, Cindy Yuet-Yin; Okada, Hajime; Miyajima, Atsushi; Itoh, Tohru

    2016-07-19

    Dynamic remodeling of the intrahepatic biliary epithelial tissue plays key roles in liver regeneration, yet the cellular basis for this process remains unclear. We took an unbiased approach based on in vivo clonal labeling and tracking of biliary epithelial cells in the three-dimensional landscape, in combination with mathematical simulation, to understand their mode of proliferation in a mouse liver injury model where the nascent biliary structure formed in a tissue-intrinsic manner. An apparent heterogeneity among biliary epithelial cells was observed: whereas most of the responders that entered the cell cycle upon injury exhibited a limited and tapering growth potential, a select population continued to proliferate, making a major contribution in sustaining the biliary expansion. Our study has highlighted a unique mode of epithelial tissue dynamics, which depends not on a hierarchical system driven by fixated stem cells, but rather, on a stochastically maintained progenitor population with persistent proliferative activity.

  4. Depth sensitive oblique polarized reflectance spectroscopy of oral epithelial tissue

    NASA Astrophysics Data System (ADS)

    Jimenez, Maria K.; Lam, Sylvia; Poh, Catherine; Sokolov, Konstantin

    2014-05-01

    Identifying depth-dependent alterations associated with epithelial cancerous lesions can be challenging in the oral cavity where variable epithelial thicknesses and troublesome keratin growths are prominent. Spectroscopic methods with enhanced depth resolution would immensely aid in isolating optical properties associated with malignant transformation. Combining multiple beveled fibers, oblique collection geometry, and polarization gating, oblique polarized reflectance spectroscopy (OPRS) achieves depth sensitive detection. We report promising results from a clinical trial of patients with oral lesions suspected of dysplasia or carcinoma demonstrating the potential of OPRS for the analysis of morphological and architectural changes in the context of multilayer, epithelial oral tissue.

  5. Three-Dimensionally Engineered Normal Human Broncho-epithelial Tissue-Like Assemblies: Target Tissues for Human Respiratory Viral Infections

    NASA Technical Reports Server (NTRS)

    Goodwin, T. J.; McCarthy, M.; Lin, Y-H

    2006-01-01

    In vitro three-dimensional (3D) human broncho-epithelial (HBE) tissue-like assemblies (3D HBE TLAs) from this point forward referred to as TLAs were engineered in Rotating Wall Vessel (RWV) technology to mimic the characteristics of in vivo tissues thus providing a tool to study human respiratory viruses and host cell interactions. The TLAs were bioengineered onto collagen-coated cyclodextran microcarriers using primary human mesenchymal bronchial-tracheal cells (HBTC) as the foundation matrix and an adult human bronchial epithelial immortalized cell line (BEAS-2B) as the overlying component. The resulting TLAs share significant characteristics with in vivo human respiratory epithelium including polarization, tight junctions, desmosomes, and microvilli. The presence of tissue-like differentiation markers including villin, keratins, and specific lung epithelium markers, as well as the production of tissue mucin, further confirm these TLAs differentiated into tissues functionally similar to in vivo tissues. Increasing virus titers for human respiratory syncytial virus (wtRSVA2) and parainfluenza virus type 3 (wtPIV3 JS) and the detection of membrane bound glycoproteins over time confirm productive infections with both viruses. Therefore, TLAs mimic aspects of the human respiratory epithelium and provide a unique capability to study the interactions of respiratory viruses and their primary target tissue independent of the host's immune system.

  6. Three-Dimensionally Engineered Normal Human Broncho-epithelial Tissue-Like Assemblies: Target Tissues for Human Respiratory Viral Infections

    NASA Technical Reports Server (NTRS)

    Goodwin, T. J.; McCarthy, M.; Lin, Y-H

    2006-01-01

    In vitro three-dimensional (3D) human broncho-epithelial (HBE) tissue-like assemblies (3D HBE TLAs) from this point forward referred to as TLAs were engineered in Rotating Wall Vessel (RWV) technology to mimic the characteristics of in vivo tissues thus providing a tool to study human respiratory viruses and host cell interactions. The TLAs were bioengineered onto collagen-coated cyclodextran microcarriers using primary human mesenchymal bronchial-tracheal cells (HBTC) as the foundation matrix and an adult human bronchial epithelial immortalized cell line (BEAS-2B) as the overlying component. The resulting TLAs share significant characteristics with in vivo human respiratory epithelium including polarization, tight junctions, desmosomes, and microvilli. The presence of tissue-like differentiation markers including villin, keratins, and specific lung epithelium markers, as well as the production of tissue mucin, further confirm these TLAs differentiated into tissues functionally similar to in vivo tissues. Increasing virus titers for human respiratory syncytial virus (wtRSVA2) and parainfluenza virus type 3 (wtPIV3 JS) and the detection of membrane bound glycoproteins over time confirm productive infections with both viruses. Therefore, TLAs mimic aspects of the human respiratory epithelium and provide a unique capability to study the interactions of respiratory viruses and their primary target tissue independent of the host's immune system.

  7. Unified quantitative characterization of epithelial tissue development.

    PubMed

    Guirao, Boris; Rigaud, Stéphane U; Bosveld, Floris; Bailles, Anaïs; López-Gay, Jesús; Ishihara, Shuji; Sugimura, Kaoru; Graner, François; Bellaïche, Yohanns

    2015-12-12

    Understanding the mechanisms regulating development requires a quantitative characterization of cell divisions, rearrangements, cell size and shape changes, and apoptoses. We developed a multiscale formalism that relates the characterizations of each cell process to tissue growth and morphogenesis. Having validated the formalism on computer simulations, we quantified separately all morphogenetic events in the Drosophila dorsal thorax and wing pupal epithelia to obtain comprehensive statistical maps linking cell and tissue scale dynamics. While globally cell shape changes, rearrangements and divisions all significantly participate in tissue morphogenesis, locally, their relative participations display major variations in space and time. By blocking division we analyzed the impact of division on rearrangements, cell shape changes and tissue morphogenesis. Finally, by combining the formalism with mechanical stress measurement, we evidenced unexpected interplays between patterns of tissue elongation, cell division and stress. Our formalism provides a novel and rigorous approach to uncover mechanisms governing tissue development.

  8. Collaboration of epithelial cells with organized mucosal lymphoid tissues.

    PubMed

    Neutra, M R; Mantis, N J; Kraehenbuhl, J P

    2001-11-01

    Immune surveillance of mucosal surfaces requires the delivery of intact macromolecules and microorganisms across epithelial barriers to organized mucosal lymphoid tissues. Transport, processing and presentation of foreign antigens, as well as local induction and clonal expansion of antigen-specific effector lymphocytes, involves a close collaboration between organized lymphoid tissues and the specialized follicle-associated epithelium. M cells in the follicle-associated epithelium transport foreign macromolecules and microorganisms to antigen-presenting cells within and under the epithelial barrier. Determination of the earliest cellular interactions that occur in and under the follicle-associated epithelium could greatly facilitate the design of effective mucosal vaccines in the future.

  9. A multicellular view of cytokinesis in epithelial tissue.

    PubMed

    Herszterg, Sophie; Pinheiro, Diana; Bellaïche, Yohanns

    2014-05-01

    The study of cytokinesis in single-cell systems provided a wealth of knowledge on the molecular and biophysical mechanisms controlling daughter cell separation. In this review, we outline recent advances in the understanding of cytokinesis in epithelial tissues. These findings provide evidence for how the cytokinetic machinery adapts to a multicellular context and how the cytokinetic machinery is itself exploited by the tissue for the preservation of tissue function and architecture during proliferation. We propose that cytokinesis in epithelia should be viewed as a multicellular process, whereby the biochemical and mechanical interactions between the dividing cell and its neighbors are essential for successful daughter cell separation while defining epithelial tissue organization and preserving tissue integrity.

  10. Gut microbiome derived metabolites modulate intestinal epithelial cell damage and mitigate Graft-versus-Host Disease

    PubMed Central

    Toubai, Tomomi; Oravecz-Wilson, Katherine; Wu, Shin-Rong; Sun, Yaping; Rossi, Corinne; Fujiwara, Hideaki; Byun, Jaeman; Shono, Yusuke; Lindemans, Caroline; Calafiore, Marco; Schmidt, Thomas C.; Honda, Kenya; Reddy, Pavan

    2016-01-01

    The impact of alterations in intestinal microbiota on microbial metabolites and on disease processes, such as graft-versus-host disease (GVHD), is not known. Here we performed unbiased analysis to identify novel alterations in gastrointestinal microbiota-derived short chain fatty acids (SCFA) after allogeneic bone marrow transplant (allo-BMT). Alterations in the amounts of only one SCFA, butyrate, were observed only within the intestinal tissue. The reduced butyrate in CD326+ intestinal epithelial cells (IECs) after allo-BMT resulted in decreased histone acetylation, which was restored upon local administration of exogenous butyrate. Butyrate restoration improved IEC junctional integrity, decreased apoptosis, and mitigated GVHD. Furthermore, alteration of the indigenous microbiota with 17 rationally selected strains of high butyrate producing Clostridia also decreased GVHD. These data demonstrate a heretofore unrecognized role of microbial metabolites and suggest that local and specific alteration of microbial metabolites has direct salutary effects on GVHD target tissues and can mitigate its severity. PMID:26998764

  11. Unified quantitative characterization of epithelial tissue development

    PubMed Central

    Guirao, Boris; Rigaud, Stéphane U; Bosveld, Floris; Bailles, Anaïs; López-Gay, Jesús; Ishihara, Shuji; Sugimura, Kaoru

    2015-01-01

    Understanding the mechanisms regulating development requires a quantitative characterization of cell divisions, rearrangements, cell size and shape changes, and apoptoses. We developed a multiscale formalism that relates the characterizations of each cell process to tissue growth and morphogenesis. Having validated the formalism on computer simulations, we quantified separately all morphogenetic events in the Drosophila dorsal thorax and wing pupal epithelia to obtain comprehensive statistical maps linking cell and tissue scale dynamics. While globally cell shape changes, rearrangements and divisions all significantly participate in tissue morphogenesis, locally, their relative participations display major variations in space and time. By blocking division we analyzed the impact of division on rearrangements, cell shape changes and tissue morphogenesis. Finally, by combining the formalism with mechanical stress measurement, we evidenced unexpected interplays between patterns of tissue elongation, cell division and stress. Our formalism provides a novel and rigorous approach to uncover mechanisms governing tissue development. DOI: http://dx.doi.org/10.7554/eLife.08519.001 PMID:26653285

  12. Engineered human broncho-epithelial tissue-like assemblies

    NASA Technical Reports Server (NTRS)

    Goodwin, Thomas J. (Inventor)

    2012-01-01

    Three-dimensional human broncho-epithelial tissue-like assemblies (TLAs) are produced in a rotating wall vessel (RWV) with microcarriers by coculturing mesenchymal bronchial-tracheal cells (BTC) and bronchial epithelium cells (BEC). These TLAs display structural characteristics and express markers of in vivo respiratory epithelia. TLAs are useful for screening compounds active in lung tissues such as antiviral compounds, cystic fibrosis treatments, allergens, and cytotoxic compounds.

  13. A dynamic cellular vertex model of growing epithelial tissues

    NASA Astrophysics Data System (ADS)

    Lin, Shao-Zhen; Li, Bo; Feng, Xi-Qiao

    2017-03-01

    Intercellular interactions play a significant role in a wide range of biological functions and processes at both the cellular and tissue scales, for example, embryogenesis, organogenesis, and cancer invasion. In this paper, a dynamic cellular vertex model is presented to study the morphomechanics of a growing epithelial monolayer. The regulating role of stresses in soft tissue growth is revealed. It is found that the cells originating from the same parent cell in the monolayer can orchestrate into clustering patterns as the tissue grows. Collective cell migration exhibits a feature of spatial correlation across multiple cells. Dynamic intercellular interactions can engender a variety of distinct tissue behaviors in a social context. Uniform cell proliferation may render high and heterogeneous residual compressive stresses, while stress-regulated proliferation can effectively release the stresses, reducing the stress heterogeneity in the tissue. The results highlight the critical role of mechanical factors in the growth and morphogenesis of epithelial tissues and help understand the development and invasion of epithelial tumors.

  14. A dynamic cellular vertex model of growing epithelial tissues

    NASA Astrophysics Data System (ADS)

    Lin, Shao-Zhen; Li, Bo; Feng, Xi-Qiao

    2017-04-01

    Intercellular interactions play a significant role in a wide range of biological functions and processes at both the cellular and tissue scales, for example, embryogenesis, organogenesis, and cancer invasion. In this paper, a dynamic cellular vertex model is presented to study the morphomechanics of a growing epithelial monolayer. The regulating role of stresses in soft tissue growth is revealed. It is found that the cells originating from the same parent cell in the monolayer can orchestrate into clustering patterns as the tissue grows. Collective cell migration exhibits a feature of spatial correlation across multiple cells. Dynamic intercellular interactions can engender a variety of distinct tissue behaviors in a social context. Uniform cell proliferation may render high and heterogeneous residual compressive stresses, while stress-regulated proliferation can effectively release the stresses, reducing the stress heterogeneity in the tissue. The results highlight the critical role of mechanical factors in the growth and morphogenesis of epithelial tissues and help understand the development and invasion of epithelial tumors.

  15. Building Epithelial Tissues from Skin Stem Cells

    PubMed Central

    Fuchs, E.; Nowak, J.A.

    2009-01-01

    The skin epidermis and its appendages provide a protective barrier that guards against loss of fluids, physical trauma, and invasion by harmful microbes. To perform these functions while confronting the harsh environs of the outside world, our body surface undergoes constant rejuvenation through homeostasis. In addition, it must be primed to repair wounds in response to injury. The adult skin maintains epidermal homeostasis, hair regeneration, and wound repair through the use of its stem cells. What are the properties of skin stem cells, when do they become established during embryogenesis, and how are they able to build tissues with such remarkably distinct architectures? How do stem cells maintain tissue homeostasis and repair wounds and how do they regulate the delicate balance between proliferation and differentiation? What is the relationship between skin cancer and mutations that perturbs the regulation of stem cells? In the past 5 years, the field of skin stem cells has bloomed as we and others have been able to purify and dissect the molecular properties of these tiny reservoirs of goliath potential. We report here progress on these fronts, with emphasis on our laboratory’s contributions to the fascinating world of skin stem cells. PMID:19022769

  16. Heterogeneity and stochastic growth regulation of biliary epithelial cells dictate dynamic epithelial tissue remodeling

    PubMed Central

    Kamimoto, Kenji; Kaneko, Kota; Kok, Cindy Yuet-Yin; Okada, Hajime; Miyajima, Atsushi; Itoh, Tohru

    2016-01-01

    Dynamic remodeling of the intrahepatic biliary epithelial tissue plays key roles in liver regeneration, yet the cellular basis for this process remains unclear. We took an unbiased approach based on in vivo clonal labeling and tracking of biliary epithelial cells in the three-dimensional landscape, in combination with mathematical simulation, to understand their mode of proliferation in a mouse liver injury model where the nascent biliary structure formed in a tissue-intrinsic manner. An apparent heterogeneity among biliary epithelial cells was observed: whereas most of the responders that entered the cell cycle upon injury exhibited a limited and tapering growth potential, a select population continued to proliferate, making a major contribution in sustaining the biliary expansion. Our study has highlighted a unique mode of epithelial tissue dynamics, which depends not on a hierarchical system driven by fixated stem cells, but rather, on a stochastically maintained progenitor population with persistent proliferative activity. DOI: http://dx.doi.org/10.7554/eLife.15034.001 PMID:27431614

  17. Multivalent Adhesion Molecule 7 Clusters Act as Signaling Platform for Host Cellular GTPase Activation and Facilitate Epithelial Barrier Dysfunction

    PubMed Central

    Lim, Jenson; Stones, Daniel H.; Krachler, Anne Marie

    2014-01-01

    Vibrio parahaemolyticus is an emerging bacterial pathogen which colonizes the gastrointestinal tract and can cause severe enteritis and bacteraemia. During infection, V. parahaemolyticus primarily attaches to the small intestine, where it causes extensive tissue damage and compromises epithelial barrier integrity. We have previously described that Multivalent Adhesion Molecule (MAM) 7 contributes to initial attachment of V. parahaemolyticus to epithelial cells. Here we show that the bacterial adhesin, through multivalent interactions between surface-induced adhesin clusters and phosphatidic acid lipids in the host cell membrane, induces activation of the small GTPase RhoA and actin rearrangements in host cells. In infection studies with V. parahaemolyticus we further demonstrate that adhesin-triggered activation of the ROCK/LIMK signaling axis is sufficient to redistribute tight junction proteins, leading to a loss of epithelial barrier function. Taken together, these findings show an unprecedented mechanism by which an adhesin acts as assembly platform for a host cellular signaling pathway, which ultimately facilitates breaching of the epithelial barrier by a bacterial pathogen. PMID:25255250

  18. Matriptase activation connects tissue factor-dependent coagulation initiation to epithelial proteolysis and signaling.

    PubMed

    Le Gall, Sylvain M; Szabo, Roman; Lee, Melody; Kirchhofer, Daniel; Craik, Charles S; Bugge, Thomas H; Camerer, Eric

    2016-06-23

    The coagulation cascade is designed to sense tissue injury by physical separation of the membrane-anchored cofactor tissue factor (TF) from inactive precursors of coagulation proteases circulating in plasma. Once TF on epithelial and other extravascular cells is exposed to plasma, sequential activation of coagulation proteases coordinates hemostasis and contributes to host defense and tissue repair. Membrane-anchored serine proteases (MASPs) play critical roles in the development and homeostasis of epithelial barrier tissues; how MASPs are activated in mature epithelia is unknown. We here report that proteases of the extrinsic pathway of blood coagulation transactivate the MASP matriptase, thus connecting coagulation initiation to epithelial proteolysis and signaling. Exposure of TF-expressing cells to factors (F) VIIa and Xa triggered the conversion of latent pro-matriptase to an active protease, which in turn cleaved the pericellular substrates protease-activated receptor-2 (PAR2) and pro-urokinase. An activation pathway-selective PAR2 mutant resistant to direct cleavage by TF:FVIIa and FXa was activated by these proteases when cells co-expressed pro-matriptase, and matriptase transactivation was necessary for efficient cleavage and activation of wild-type PAR2 by physiological concentrations of TF:FVIIa and FXa. The coagulation initiation complex induced rapid and prolonged enhancement of the barrier function of epithelial monolayers that was dependent on matriptase transactivation and PAR2 signaling. These observations suggest that the coagulation cascade engages matriptase to help coordinate epithelial defense and repair programs after injury or infection, and that matriptase may contribute to TF-driven pathogenesis in cancer and inflammation.

  19. Matriptase activation connects tissue factor–dependent coagulation initiation to epithelial proteolysis and signaling

    PubMed Central

    Le Gall, Sylvain M.; Szabo, Roman; Lee, Melody; Kirchhofer, Daniel; Craik, Charles S.; Bugge, Thomas H.

    2016-01-01

    The coagulation cascade is designed to sense tissue injury by physical separation of the membrane-anchored cofactor tissue factor (TF) from inactive precursors of coagulation proteases circulating in plasma. Once TF on epithelial and other extravascular cells is exposed to plasma, sequential activation of coagulation proteases coordinates hemostasis and contributes to host defense and tissue repair. Membrane-anchored serine proteases (MASPs) play critical roles in the development and homeostasis of epithelial barrier tissues; how MASPs are activated in mature epithelia is unknown. We here report that proteases of the extrinsic pathway of blood coagulation transactivate the MASP matriptase, thus connecting coagulation initiation to epithelial proteolysis and signaling. Exposure of TF-expressing cells to factors (F) VIIa and Xa triggered the conversion of latent pro-matriptase to an active protease, which in turn cleaved the pericellular substrates protease-activated receptor-2 (PAR2) and pro-urokinase. An activation pathway-selective PAR2 mutant resistant to direct cleavage by TF:FVIIa and FXa was activated by these proteases when cells co-expressed pro-matriptase, and matriptase transactivation was necessary for efficient cleavage and activation of wild-type PAR2 by physiological concentrations of TF:FVIIa and FXa. The coagulation initiation complex induced rapid and prolonged enhancement of the barrier function of epithelial monolayers that was dependent on matriptase transactivation and PAR2 signaling. These observations suggest that the coagulation cascade engages matriptase to help coordinate epithelial defense and repair programs after injury or infection, and that matriptase may contribute to TF-driven pathogenesis in cancer and inflammation. PMID:27114461

  20. Re-epithelialization: a key element in tracheal tissue engineering.

    PubMed

    Zhang, Hengyi; Fu, Wei; Xu, Zhiwei

    2015-11-01

    Trachea-tissue engineering is a thriving new field in regenerative medicine that is reaching maturity and yielding numerous promising results. In view of the crucial role that the epithelium plays in the trachea, re-epithelialization of tracheal substitutes has gradually emerged as the focus of studies in tissue-engineered trachea. Recent progress in our understanding of stem cell biology, growth factor interactions and transplantation immunobiology offer the prospect of optimization of a tissue-engineered tracheal epithelium. In addition, advances in cell culture technology and successful applications of clinical transplantation are opening up new avenues for the construction of a tissue-engineered tracheal epithelium. Therefore, this review summarizes current advances, unresolved obstacles and future directions in the reconstruction of a tissue-engineered tracheal epithelium.

  1. Endomicroscopy imaging of epithelial structures using tissue autofluorescence

    NASA Astrophysics Data System (ADS)

    Lin, Bevin; Urayama, Shiro; Saroufeem, Ramez M. G.; Matthews, Dennis L.; Demos, Stavros G.

    2011-04-01

    We explore autofluorescence endomicroscopy as a potential tool for real-time visualization of epithelial tissue microstructure and organization in a clinical setting. The design parameters are explored using two experimental systems--an Olympus Medical Systems Corp. stand-alone clinical prototype probe, and a custom built bench-top rigid fiber conduit prototype. Both systems entail ultraviolet excitation at 266 nm and/or 325 nm using compact laser sources. Preliminary results using ex vivo animal and human tissue specimens suggest that this technology can be translated toward in vivo application to address the need for real-time histology.

  2. Regulation of Host Epithelial Responses to Cryptosporidium Infection by MicroRNAs.

    PubMed

    Ming, Zhenping; Zhou, Rui; Chen, Xian-Ming

    2016-12-15

    Cryptosporidium species infect the gastrointestinal epithelium and other mucosal surfaces of vertebrate hosts. Epithelial cells provide the first line of defense against Cryptosporidium infection and play a critical role in the initiation, regulation, and resolution of both innate and adaptive immune reactions. Host miRNAs in mammalian cells have been shown to play crucial roles in cellular responses to infection by diverse pathogens, including viruses, parasites, and bacteria. Given the absence of RNAi machinery in Cryptosporidium, lack of miRNA expression in the parasite, and minimal invasion nature of infection, Cryptosporidium infection provides an ideal model for exploring miRNA-mediated epithelial cell defense, relevant to infection of mucosal epithelial cells by pathogens in general. Increasing evidence supports that miRNAs may modulate many stages of epithelial responses following Cryptosporidium infection, including activation of the intracellular signaling pathways, production of antimicrobial molecules, expression of cytokines/chemokines, release of epithelial cell-derived exosomes, and feedback regulation of immune homeostasis. On the other hand, this parasite may have developed strategies to modulate host miRNA-mediated cellular function for immune evasion. In this review, we will summarize the recent advances on miRNA regulation of epithelial responses to Cryptosporidium infection, with an emphasis on host defense and parasite immune evasion. This article is protected by copyright. All rights reserved.

  3. Spraying Respiratory Epithelial Cells to Coat Tissue-Engineered Constructs

    PubMed Central

    Thiebes, Anja Lena; Albers, Stefanie; Klopsch, Christian; Jockenhoevel, Stefan; Cornelissen, Christian G.

    2015-01-01

    Abstract Applying cells in a spray can overcome current hurdles in coating tissue engineered constructs with a thin layer of endo- or epithelial cells. We report here a structured study on the influences of spray application with a medical spray device on vascular smooth muscle cells (vSMCs) and respiratory epithelial cells (RECs) with and without fibrin gel. Next to viability and cytotoxicity assays, the in vitro differentiation capacity after spray processing was analyzed. For vSMC, no influence of air pressures till 0.8 bar could be shown, whereas the viability decreased for higher pressures. The viability of RECs was reduced to 88.5% with 0.4 bar air pressure. Lactate dehydrogenase-levels in the culture medium increased the first day after spraying but normalized afterward. In the short term, no differences by means of morphology and expression-specific markers for vSMCs and RECs were seen between the control and study group. In addition, in a long-term study for 28 days with the air–liquid interface, RECs differentiated and built up an organized epithelial layer with ciliary development that was comparable to the control for cells sprayed without fibrin gel. When spraying within fibrin gel, ciliary development was lower at 28 days. Thus, spraying of vSMCs and RECs was proved to be a suitable method for tissue engineering. Especially for RECs, this application is of special significance when coating luminal structures or other unfavorable topographies. PMID:26309803

  4. Volumetric imaging of oral epithelial neoplasia by MPM-SHGM: epithelial connective tissue interface (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Pal, Rahul; Yang, Jinping; Qiu, Suimin; Resto, Vicente; McCammon, Susan; Vargas, Gracie

    2016-03-01

    The majority of oral cancers are comprised of oral squamous cell carcinoma in which neoplastic epithelial cells invade across the epithelial connective tissue interface (ECTI). Invasion is preceded by a multi-component process including epithelial hyperproliferation, loss of cell polarity, and remodeling of the extracellular matrix. Multiphoton Autofluorescence Microscopy (MPAM) and Second Harmonic Generation Microscopy (SHGM) show promise for revealing indicators of neoplasia. In particular, volumetric imaging by these methods can reveal aspects of the 3D microstructure that are not possible by other methods and which could both further our understanding of neoplastic transformation and be explored for development of diagnostic approaches in this disease having only 55% 5-year survival rate. MPAM-SHG were applied to reveal the 3D structure of the critical ECTI interface that plays an integral part toward invasion. Epithelial dysplasia was induced in an established hamster model. MPAM-SHGM was applied to lesion sites, using 780 nm excitation (450-600nm emission) for autofluroescence of cellular and extracellular components; 840 nm using 420 nm bandpass filter for SHG. The ECTI surface was identified as the interface at which SHG signal began following the epithelium and was modeled as a 3D surface using Matlab. ECTI surface area and cell features at sites of epithelial expansion where ECTI was altered were measured; Imaged sites were biopsied and processed for histology. ROC analysis using ECTI image metrics indicated the ability to delineate normal from neoplasia with high sensitivity and specificity and it is noteworthy that inflammation did not significantly alter diagnostic potential of MPAM-SHGM .

  5. Isolation of Endoplasmic Reticulum Fractions from Mammary Epithelial Tissue.

    PubMed

    Chanat, Eric; Le Parc, Annabelle; Lahouassa, Hichem; Badaoui, Bouabid

    2016-06-01

    In the mammary glands of lactating animals, the mammary epithelial cells that surround the lumen of the acini produce and secrete copious amounts of milk. Functional differentiation of these mammary epithelial cells depends on the development of high-efficiency secretory pathways, notably for protein and lipid secretion. Protein secretion is a fundamental process common to all animal cells that involves a subset of cellular organelles, including the endoplasmic reticulum and the Golgi apparatus. In contrast, en masse secretion of triglycerides and cholesterol esters in the form of milk fat globules is a unique feature of the mammary epithelial cell. Cytoplasmic lipid droplets, the intracellular precursors of milk fat globules, originate from the endoplasmic reticulum, as do most milk-specific proteins. This organelle is therefore pivotal in the biogenesis of milk components. Fractionation of the cell into its subcellular parts is an approach that has proven very powerful for understanding organelle function and for studying the specific role of an organelle in a given cell activity. Here we describe a method for the purification of both smooth and rough microsomes, the membrane-bound endoplasmic reticulum fragments that form from endoplasmic reticulum domains when cells are broken up, from mammary gland tissue at lactation.

  6. Depth-cumulated epithelial redox ratio and stromal collagen quantity as quantitative intrinsic indicators for differentiating normal, inflammatory, and dysplastic epithelial tissues

    NASA Astrophysics Data System (ADS)

    Zhuo, Shuangmu; Zheng, Liqin; Chen, Jianxin; Xie, Shusen; Zhu, Xiaoqin; Jiang, Xingshan

    2010-10-01

    Multiphoton microscopy was used to isolate the intrinsic emission contribution of epithelial cellular origins and stromal collagen in normal, inflammatory, and dysplastic epithelial tissues, and quantify the depth-cumulated epithelial redox ratio and stromal collagen quantity. It was found that both inflammatory and dysplastic epithelial tissues display a large decrease in stromal collagen quantity but have very different epithelial redox ratio. These results suggest that probing differences in epithelial redox ratio in addition to stromal collagen quantity can serve as quantitative intrinsic indicators for differentiating normal, inflammatory, and dysplastic epithelial tissues.

  7. Human epithelial tissue culture study on restorative materials.

    PubMed

    Forster, András; Ungvári, Krisztina; Györgyey, Ágnes; Kukovecz, Ákos; Turzó, Kinga; Nagy, Katalin

    2014-01-01

    Health condition of the gingival tissues contacting the surfaces of fixed prostheses is a result of multiple etiologic factors. The aim of the investigation discussed here was to evaluate the attachment and proliferation rate of cultured human epithelial cells on three commonly used restorative materials under in vitro conditions. Morphological and chemical structure of polished lithium-disilicate (IPS e.max Press, Ivoclar Vivadent AG, Germany), yttrium modified zirconium dioxide (5-TEC ICE Zirkon Translucent, Zirkonzahn GmbH Srl, Germany) and cobalt chromium alloy (Remanium star, Dentaurum GmbH & Co. KG, Germany) discs were examined by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and atomic force microscopy (AFM). Human epithelial cells harvested and cultured from one donor, were applied to investigate cell attachment (24h observation) and proliferation (72h observation) via dimethylthiazol-diphenyl tetrazolium bromide (MTT) and AlamarBlue(®) (AB) assays on control surface (cell-culture plate) and on the restorative materials (n=3×20 specimens/material). SEM and AFM revealed typical morphology and roughness features for the materials. Zirconia presented significantly higher Ra value. EDS confirmed typical elements on the investigated restorative materials: lithium-disilicate (Si, O); Zirconia (Zi, Y, O); CoCr (Co, Cr, W). All surfaces except CoCr exhibited significant cell proliferation according to MTT and AB assays after 72h compared to 24h. Among the restorative materials, CoCr samples showed the highest cell attachment as indicated by MTT assay. AB results showed that attachment and proliferation of human epithelial cells is supported more on lithium-disilicate. Both assays indicated the lowest value for zirconia. The results indicate that the restorative materials examined are equally suitable for subgingival restorations. Lithium-disilicate exhibited the best biocompatibility. The examined materials are indicated for use

  8. Pathogenesis of Dermatophytosis: Sensing the Host Tissue.

    PubMed

    Martinez-Rossi, Nilce M; Peres, Nalu T A; Rossi, Antonio

    2017-02-01

    The genera Trichophyton, Microsporum, and Epidermophyton include filamentous fungi that cause dermatophytosis, a superficial infection of the skin, stratum corneum, nail beds, and hair follicles. The ability of dermatophytes to adhere to these substrates and adapt to the host environment is essential for the establishment of infection. Several fungal enzymes and proteins participate in this adaptive response to the environment and to keratin degradation. Transcription factors such as PacC and Hfs1, as well as heat shock proteins, are involved in sensing and adapting to the acidic pH of the skin in the early stages of fungal-host interaction. During dermatophyte growth, with keratin as the sole carbon source, the extracellular pH shifts from acidic to alkaline. This creates an environment in which most of the known keratinolytic proteases exhibit optimal activity. These events culminate in the establishment and maintenance of the infection, which can be chronic or acute depending on the dermatophyte species. This review focuses on these and other molecular aspects of the dermatophyte-host interaction.

  9. Tissue kallikrein activation of the epithelial Na channel

    PubMed Central

    Patel, Ankit B.; Chao, Julie

    2012-01-01

    Epithelial Na Channels (ENaC) are responsible for the apical entry of Na+ in a number of different epithelia including the renal connecting tubule and cortical collecting duct. Proteolytic cleavage of γ-ENaC by serine proteases, including trypsin, furin, elastase, and prostasin, has been shown to increase channel activity. Here, we investigate the ability of another serine protease, tissue kallikrein, to regulate ENaC. We show that excretion of tissue kallikrein, which is secreted into the lumen of the connecting tubule, is stimulated following 5 days of a high-K+ or low-Na+ diet in rats. Urinary proteins reconstituted in a low-Na buffer activated amiloride-sensitive currents (INa) in ENaC-expressing oocytes, suggesting an endogenous urinary protease can activate ENaC. We next tested whether tissue kallikrein can directly cleave and activate ENaC. When rat ENaC-expressing oocytes were exposed to purified tissue kallikrein from rat urine (RTK), ENaC currents increased threefold in both the presence and absence of a soybean trypsin inhibitor (SBTI). RTK and trypsin both decreased the apparent molecular mass of cleaved cell-surface γ-ENaC, while immunodepleted RTK produced no shift in apparent molecular mass, demonstrating the specificity of the tissue kallikrein. A decreased effect of RTK on Xenopus ENaC, which has variations in the putative prostasin cleavage sites in γ-ENaC, suggests these sites are important in RTK activation of ENaC. Mutating the prostasin site in mouse γ-ENaC (γRKRK186QQQQ) abolished ENaC activation and cleavage by RTK while wild-type mouse ENaC was activated and cleaved similar to that of the rat. We conclude that tissue kallikrein can be a physiologically relevant regulator of ENaC activity. PMID:22622459

  10. Nanostructure-Mediated Transport of Biologics across Epithelial Tissue: Enhancing Permeability via Nanotopography

    PubMed Central

    Kam, Kimberly R.; Walsh, Laura A.; Bock, Suzanne M.; Koval, Michael; Fischer, Kathleen E.; Ross, Russell F.; Desai, Tejal A.

    2015-01-01

    Herein, we demonstrate that nanotopographical cues can be utilized to enable biologics >66 kDa to be transported across epithelial monolayers. When placed in contact with epithelial monolayers, nanostructured thin films loosen the epithelial barrier and allow for significantly increased transport of FITC-albumin, FITC-IgG, and a model therapeutic, etanercept. Our work highlights the potential to use drug delivery systems which incorporate nanotopography to increase the transport of biologics across epithelial tissue. PMID:23186530

  11. Binding of Host Factors Influences Internalization and Intracellular Trafficking of Streptococcus uberis in Bovine Mammary Epithelial Cells

    PubMed Central

    Almeida, Raul A.; Dunlap, John R.; Oliver, Stephen P.

    2010-01-01

    We showed that internalization of Streptococcus uberis into bovine mammary epithelial cells occurred through receptor- (RME) and caveolae-mediated endocytosis (CME). We reported also that treatment of S. uberis with host proteins including lactoferrin (LF) enhanced its internalization into host cells. Since the underlying mechanism(s) involved in such enhancement was unknown we investigated if preincubation of S. uberis with host proteins drives internalization of this pathogen into host cells through CME. Thus, experiments involving coculture of collagen-, fibronectin-, and LF-pretreated S. uberis with bovine mammary epithelial cells treated with RME and CME inhibitors were conducted. Results showed that internalization of host proteins-pretreated S. uberis into mammary epithelial cells treated with RME inhibitors was higher than that of untreated controls. These results suggest that pretreatment with selected host proteins commits S. uberis to CME, thus avoiding intracellular bactericidal mechanisms and allowing its persistence into bovine mammary epithelial cells. PMID:20614000

  12. Cryopreservation of tissue-engineered epithelial sheets in trehalose.

    PubMed

    Chen, Fanfan; Zhang, Wenjie; Wu, Wei; Jin, Yuqing; Cen, Lian; Kretlow, James D; Gao, Weicheng; Dai, Zhenpeng; Wang, Jiaming; Zhou, Guangdong; Liu, Wei; Cui, Lei; Cao, Yilin

    2011-11-01

    Tissue-engineered epidermal membranes are useful for clinical wound healing. To facilitate these products in the clinic, optimized storage methods need to be developed. We studied the efficiency of extracellular trehalose at various concentrations for cryopreserving human tissue-engineered epidermal membranes compared with that of dimethyl-sulfoxide (DMSO) used by most organ banks for cryopreserving skin grafts and artificial skin substitutes. Keratinocyte (KC) viability, proliferation and marker expression following cryopreservation in trehalose were examined with similar results to those using DMSO. Trehalose concentration (0.4m) was optimized according to the described cellular activities following cryopreservation. Artificial epidermal substitutes were then cryopreserved in trehalose at the optimized concentration. Cell viability, growth factor secretion and wound healing properties of cryopreserved artificial epidermal substitutes using nude mice were examined and compared with those of DMSO cryopreservation. Cryopreservation with trehalose enhanced human KC viability in suspension and artificial skin substitutes. In addition, trehalose cryopreservation provided fast recovery of EGF and TGF-β1 secretion by KCs after thawing. When transplanted into nude mice, trehalose-cryopreserved artificial skin repaired skin defects in a similar manner to that of a non-cryopreserved control. Moreover, trehalose-cryopreserved artificial skin resulted in engraftment and wound closure that was significantly enhanced compared with that of DMSO-cryopreserved epidermal membranes. The results indicate that the use of trehalose improves cryopreservation of tissue-engineered epithelial sheets. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Carcinoma cells misuse the host tissue damage response to invade the brain.

    PubMed

    Chuang, Han-Ning; van Rossum, Denise; Sieger, Dirk; Siam, Laila; Klemm, Florian; Bleckmann, Annalen; Bayerlová, Michaela; Farhat, Katja; Scheffel, Jörg; Schulz, Matthias; Dehghani, Faramarz; Stadelmann, Christine; Hanisch, Uwe-Karsten; Binder, Claudia; Pukrop, Tobias

    2013-08-01

    The metastatic colonization of the brain by carcinoma cells is still barely understood, in particular when considering interactions with the host tissue. The colonization comes with a substantial destruction of the surrounding host tissue. This leads to activation of damage responses by resident innate immune cells to protect, repair, and organize the wound healing, but may distract from tumoricidal actions. We recently demonstrated that microglia, innate immune cells of the CNS, assist carcinoma cell invasion. Here we report that this is a fatal side effect of a physiological damage response of the brain tissue. In a brain slice coculture model, contact with both benign and malignant epithelial cells induced a response by microglia and astrocytes comparable to that seen at the interface of human cerebral metastases. While the glial damage response intended to protect the brain from intrusion of benign epithelial cells by inducing apoptosis, it proved ineffective against various malignant cell types. They did not undergo apoptosis and actually exploited the local tissue reaction to invade instead. Gene expression and functional analyses revealed that the C-X-C chemokine receptor type 4 (CXCR4) and WNT signaling were involved in this process. Furthermore, CXCR4-regulated microglia were recruited to sites of brain injury in a zebrafish model and CXCR4 was expressed in human stroke patients, suggesting a conserved role in damage responses to various types of brain injuries. Together, our findings point to a detrimental misuse of the glial damage response program by carcinoma cells resistant to glia-induced apoptosis.

  14. Preexisting epithelial diversity in normal human livers: a tissue-tethered cytometric analysis in portal/periportal epithelial cells.

    PubMed

    Isse, Kumiko; Lesniak, Andrew; Grama, Kedar; Maier, John; Specht, Susan; Castillo-Rama, Marcela; Lunz, John; Roysam, Badrinath; Michalopoulos, George; Demetris, Anthony J

    2013-04-01

    Routine light microscopy identifies two distinct epithelial cell populations in normal human livers: hepatocytes and biliary epithelial cells (BECs). Considerable epithelial diversity, however, arises during disease states when a variety of hepatocyte-BEC hybrid cells appear. This has been attributed to activation and differentiation of putative hepatic progenitor cells (HPC) residing in the canals of Hering and/or metaplasia of preexisting mature epithelial cells. A novel analytic approach consisting of multiplex labeling, high-resolution whole-slide imaging (WSI), and automated image analysis was used to determine if more complex epithelial cell phenotypes preexist in normal adult human livers, which might provide an alternative explanation for disease-induced epithelial diversity. "Virtually digested" WSI enabled quantitative cytometric analyses of individual cells displayed in a variety of formats (e.g., scatterplots) while still tethered to the WSI and tissue structure. We employed biomarkers specifically associated with mature epithelial forms (HNF4α for hepatocytes, CK19 and HNF1β for BEC) and explored for the presence of cells with hybrid biomarker phenotypes. The results showed abundant hybrid cells in portal bile duct BEC, canals of Hering, and immediate periportal hepatocytes. These bipotential cells likely serve as a reservoir for the epithelial diversity of ductular reactions, appearance of hepatocytes in bile ducts, and the rapid and fluid transition of BEC to hepatocytes, and vice versa. Novel imaging and computational tools enable increased information extraction from tissue samples and quantify the considerable preexistent hybrid epithelial diversity in normal human liver. This computationally enabled tissue analysis approach offers much broader potential beyond the results presented here. Copyright © 2012 American Association for the Study of Liver Diseases.

  15. Thicker host tissues moderate light stress in a cnidarian endosymbiont.

    PubMed

    Dimond, James L; Holzman, Benjamin J; Bingham, Brian L

    2012-07-01

    The susceptibility of algal-cnidarian holobionts to environmental stress is dependent on attributes of both host and symbiont, but the role of the host is often unclear. We examined the influence of the host on symbiont light stress, comparing the photophysiology of the chlorophyte symbiont Elliptochloris marina in two species of sea anemones in the genus Anthopleura. After 3 months of acclimation in outdoor tanks, polyp photoprotective contraction behavior was similar between the two host species, but photochemical efficiency was 1.5 times higher in A. xanthogrammica than in A. elegantissima. Maximum relative electron transport rates, derived from rapid light curves, were 1.5 times higher in A. xanthogrammica than in A. elegantissima when symbionts were inside intact tissues, but were not significantly different between host species upon removal of outer (epidermis and mesoglea) tissue layers from symbiont-containing gastrodermal cells. Tissues of A. xanthogrammica were 1.8 times thicker than those of A. elegantissima, with outer tissue layers attenuating 1.6 times more light. We found no significant differences in light absorption properties per unit volume of tissue, confirming the direct effect of tissue thickness on light attenuation. The thicker tissues of A. xanthogrammica thus provide a favorable environment for E. marina - a relatively stress-susceptible symbiont - and may explain its higher prevalence and expanded range in A. xanthogrammica along the Pacific coast of North America. Our findings also support a photoprotective role for thicker host tissues in reef corals that has long been thought to influence variability in bleaching susceptibility among coral taxa.

  16. Chitin-based Materials in Tissue Engineering: Applications in Soft Tissue and Epithelial Organ

    PubMed Central

    Yang, Tsung-Lin

    2011-01-01

    Chitin-based materials and their derivatives are receiving increased attention in tissue engineering because of their unique and appealing biological properties. In this review, we summarize the biomedical potential of chitin-based materials, specifically focusing on chitosan, in tissue engineering approaches for epithelial and soft tissues. Both types of tissues play an important role in supporting anatomical structures and physiological functions. Because of the attractive features of chitin-based materials, many characteristics beneficial to tissue regeneration including the preservation of cellular phenotype, binding and enhancement of bioactive factors, control of gene expression, and synthesis and deposition of tissue-specific extracellular matrix are well-regulated by chitin-based scaffolds. These scaffolds can be used in repairing body surface linings, reconstructing tissue structures, regenerating connective tissue, and supporting nerve and vascular growth and connection. The novel use of these scaffolds in promoting the regeneration of various tissues originating from the epithelium and soft tissue demonstrates that these chitin-based materials have versatile properties and functionality and serve as promising substrates for a great number of future applications. PMID:21673932

  17. Chitin-based materials in tissue engineering: applications in soft tissue and epithelial organ.

    PubMed

    Yang, Tsung-Lin

    2011-01-01

    Chitin-based materials and their derivatives are receiving increased attention in tissue engineering because of their unique and appealing biological properties. In this review, we summarize the biomedical potential of chitin-based materials, specifically focusing on chitosan, in tissue engineering approaches for epithelial and soft tissues. Both types of tissues play an important role in supporting anatomical structures and physiological functions. Because of the attractive features of chitin-based materials, many characteristics beneficial to tissue regeneration including the preservation of cellular phenotype, binding and enhancement of bioactive factors, control of gene expression, and synthesis and deposition of tissue-specific extracellular matrix are well-regulated by chitin-based scaffolds. These scaffolds can be used in repairing body surface linings, reconstructing tissue structures, regenerating connective tissue, and supporting nerve and vascular growth and connection. The novel use of these scaffolds in promoting the regeneration of various tissues originating from the epithelium and soft tissue demonstrates that these chitin-based materials have versatile properties and functionality and serve as promising substrates for a great number of future applications.

  18. Examination of epithelial tissue cytokine response to natural peste des petits ruminants virus (PPRV) infection in sheep and goats by immunohistochemistry.

    PubMed

    Atmaca, H T; Kul, O

    2012-01-01

    In this study, we aimed to evaluate expression of IL-4, IL-10, TNF-α, IFN-γ and iNOS in lingual, buccal mucosa and lung epithelial tissue using immunoperoxidase technique and to compare with the tissues of control animals. The tissues used in the study were collected from 17 PPRV-affected and 5 healthy sheep and goats. In PPRV positive animals, the lungs, lingual and buccal mucosa had significantly higher iNOS, IFN-γ and TNF-α expressions compared to control group animals. There was no significant difference between PPRV positive and control groups for IL-4 and IL-10 expressions of epithelial tissues. In conclusion, the epithelial tissues infected by PPRV showed significant iNOS, IFN-γ and TNF-α expressions and they might play an important role in the initiation and regulation of cytokine response, as they take place in the first host barrier to be in contact with PPRV. It is suggested that the more epithelial damage produced by PPRV the more cytokine response may result in the infected epithelial cells. The first demonstration of iNOS expression and epithelial cytokine response to PPRV in natural cases is important because it may contribute to an early initiation of systemic immunity against PPRV infection, in addition to direct elimination of the virus during the initial epithelial phase of the infection.

  19. Host-derived extracellular RNA promotes adhesion of Streptococcus pneumoniae to endothelial and epithelial cells

    PubMed Central

    Zakrzewicz, Dariusz; Bergmann, Simone; Didiasova, Miroslava; Giaimo, Benedetto Daniele; Borggrefe, Tilman; Mieth, Maren; Hocke, Andreas C.; Lochnit, Guenter; Schaefer, Liliana; Hammerschmidt, Sven; Preissner, Klaus T.; Wygrecka, Malgorzata

    2016-01-01

    Streptococcus pneumoniae is the most frequent cause of community-acquired pneumonia. The infection process involves bacterial cell surface receptors, which interact with host extracellular matrix components to facilitate colonization and dissemination of bacteria. Here, we investigated the role of host-derived extracellular RNA (eRNA) in the process of pneumococcal alveolar epithelial cell infection. Our study demonstrates that eRNA dose-dependently increased S. pneumoniae invasion of alveolar epithelial cells. Extracellular enolase (Eno), a plasminogen (Plg) receptor, was identified as a novel eRNA-binding protein on S. pneumoniae surface, and six Eno eRNA-binding sites including a C-terminal 15 amino acid motif containing lysine residue 434 were characterized. Although the substitution of lysine 434 for glycine (K434G) markedly diminished the binding of eRNA to Eno, the adherence to and internalization into alveolar epithelial cells of S. pneumoniae strain carrying the C-terminal lysine deletion and the mutation of internal Plg-binding motif were only marginally impaired. Accordingly, using a mass spectrometric approach, we identified seven novel eRNA-binding proteins in pneumococcal cell wall. Given the high number of eRNA-interacting proteins on pneumococci, treatment with RNase1 completely inhibited eRNA-mediated pneumococcal alveolar epithelial cell infection. Our data support further efforts to employ RNAse1 as an antimicrobial agent to combat pneumococcal infectious diseases. PMID:27892961

  20. Invasion of Host Cells and Tissues by Uropathogenic Bacteria

    PubMed Central

    Lewis, Adam J.; Richards, Amanda C.; Mulvey, Matthew A.

    2016-01-01

    Within the mammalian urinary tract uropathogenic bacteria face many challenges, including the shearing flow of urine, numerous antibacterial molecules, the bactericidal effects of phagocytes, and a scarcity of nutrients. These problems may be circumvented in part by the ability of uropathogenic Escherichia coli (UPEC) and several other uropathogens to invade the epithelial cells that line the urinary tract. By entering host cells, uropathogens can gain access to additional nutrients and protection from both host defenses and antibiotic treatments. Translocation through host cells can facilitate bacterial dissemination within the urinary tract, while the establishment of stable intracellular bacterial populations may create reservoirs for relapsing and chronic urinary tract infections (UTIs). Here we review the mechanisms and consequences of host cell invasion by uropathogenic bacteria, with consideration of the defenses that are brought to bear against facultative intracellular pathogens within the urinary tract. The relevance of host cell invasion to the pathogenesis of UTIs in human patients is also assessed, along with some of the emerging treatment options that build upon our growing understanding of the infectious life cycle of UPEC and other uropathogenic bacteria. PMID:28087946

  1. Neutrophils: Between Host Defence, Immune Modulation, and Tissue Injury

    PubMed Central

    Kruger, Philipp; Saffarzadeh, Mona; Weber, Alexander N. R.; Rieber, Nikolaus; Radsak, Markus; von Bernuth, Horst; Benarafa, Charaf; Roos, Dirk; Skokowa, Julia; Hartl, Dominik

    2015-01-01

    Neutrophils, the most abundant human immune cells, are rapidly recruited to sites of infection, where they fulfill their life-saving antimicrobial functions. While traditionally regarded as short-lived phagocytes, recent findings on long-term survival, neutrophil extracellular trap (NET) formation, heterogeneity and plasticity, suppressive functions, and tissue injury have expanded our understanding of their diverse role in infection and inflammation. This review summarises our current understanding of neutrophils in host-pathogen interactions and disease involvement, illustrating the versatility and plasticity of the neutrophil, moving between host defence, immune modulation, and tissue damage. PMID:25764063

  2. Characterization of SP41, a surface protein of Brucella associated with adherence and invasion of host epithelial cells.

    PubMed

    Castañeda-Roldán, Elsa I; Ouahrani-Bettache, Safia; Saldaña, Zeus; Avelino, Fabiola; Rendón, María A; Dornand, Jacques; Girón, Jorge A

    2006-12-01

    Brucella is an invasive organism that multiplies and survives within eukaryotic cells. The brucellae are able to adhere to the surface of cultured epithelial cells, a mechanism that may facilitate penetration and dissemination to other host tissues. However, no adhesins that allow the bacteria to interact with the surface of epithelial cells before migration within polymorphonuclear leukocytes, monocytes and macrophages have been described. Here, we show that Brucella surface proteins (SPs) with apparent molecular masses of 14, 18 and 41 kDa bound selectively to HeLa cells. However, only antibodies directed against the 41 kDa surface protein (SP41) inhibited in dose-response manner, bacterial adherence and invasion of HeLa cells. HeLa cells treated with neuraminidase did not bind SP41, suggesting the involvement of cellular sialic acid residues in this interaction. Biochemical analysis of SP41 revealed that this protein is the predicted product of the ugpB locus, which showed significant homology to the glycerol-3-phosphate-binding ATP-binding cassette (ABC) transporter protein found in several bacterial species. SP41 appears to be exposed on the bacterial surface as determined by immunofluorescence and immunogold labelling with anti-SP41 antibody. An isogenic DeltaugpB mutant showed a significant inhibitory effect on Brucella adherence and invasion of human cultured epithelial cells and this effect could be reversed by restoration of the ugpB on a plasmid. Lastly, we also show that most of the sera from individuals with acute brucellosis, but not sera obtained from healthy donors or patients with chronic brucellosis, mount antibody reactivity against SP41, suggesting that this protein is produced in vivo and that it elicits an antibody immune response. These data are novel findings that offer new insights into understanding the interplay between this bacterium and host target cells, and identify a new target for vaccine development and prevention of brucellosis.

  3. Host-pathogen interactions during coronavirus infection of primary alveolar epithelial cells

    PubMed Central

    Miura, Tanya A.; Holmes, Kathryn V.

    2009-01-01

    Viruses that infect the lung are a significant cause of morbidity and mortality in animals and humans worldwide. Coronaviruses are being associated increasingly with severe diseases in the lower respiratory tract. Alveolar epithelial cells are an important target for coronavirus infection in the lung, and infected cells can initiate innate immune responses to viral infection. In this overview, we describe in vitro models of highly differentiated alveolar epithelial cells that are currently being used to study the innate immune response to coronavirus infection. We have shown that rat coronavirus infection of rat alveolar type I epithelial cells in vitro induces expression of CXC chemokines, which may recruit and activate neutrophils. Although neutrophils are recruited early in infection in several coronavirus models including rat coronavirus. However, their role in viral clearance and/or immune-mediated tissue damage is not understood. Primary cultures of differentiated alveolar epithelial cells will be useful for identifying the interactions between coronaviruses and alveolar epithelial cells that influence the innate immune responses to infection in the lung. Understanding the molecular details of these interactions will be critical for the design of effective strategies to prevent and treat coronavirus infections in the lung. PMID:19638499

  4. Using Organotypic Epithelial Tissue Culture to Study the Human Papillomavirus Life Cycle.

    PubMed

    Lee, Denis; Norby, Kathryn; Hayes, Mitchell; Chiu, Ya-Fang; Sugden, Bill; Lambert, Paul F

    2016-05-06

    Human papillomaviruses (HPVs) are small double-stranded DNA viruses that are associated with greater than 95% of cervical cancers and 20% of head and neck cancers. These cancers arise from persistent infections in which there is continued expression of the HPV E6 and E7 oncogenes, often as a consequence of integration of HPV DNA into the host genome. Such cancers represent "dead ends" for the virus as integration disrupts the viral genome and because the cancers are defective in normal epithelial differentiation, which is required for production of progeny papillomavirus. In order to study the full viral life cycle, from the establishment to maintenance to productive stages, our lab makes use of the organotypic epithelial tissue culture system. This system allows us to mimic the three-dimensional structure of epithelia whose differentiation is tightly linked to the completion of the HPV viral life cycle. In this chapter we describe how various aspects of the HPV life cycle are monitored in raft cultures making use of an immortalized keratinocyte cell line. © 2016 by John Wiley & Sons, Inc.

  5. Host-Pathogen Interactions of Actinobacillus pleuropneumoniae with Porcine Lung and Tracheal Epithelial Cells▿ †

    PubMed Central

    Auger, Eliane; Deslandes, Vincent; Ramjeet, Mahendrasingh; Contreras, Irazù; Nash, John H. E.; Harel, Josée; Gottschalk, Marcelo; Olivier, Martin; Jacques, Mario

    2009-01-01

    Host-pathogen interactions are of great importance in understanding the pathogenesis of infectious microorganisms. We developed in vitro models to study the host-pathogen interactions of porcine respiratory tract pathogens using two immortalized epithelial cell lines, namely, the newborn pig trachea (NPTr) and St. Jude porcine lung (SJPL) cell lines. We first studied the interactions of Actinobacillus pleuropneumoniae, an important swine pathogen, using these models. Under conditions where cytotoxicity was absent or low, we showed that A. pleuropneumoniae adheres to both cell lines, stimulating the induction of NF-κB. The NPTr cells consequently secrete interleukin 8, while the SJPL cells do not, since they are deprived of the NF-κB p65 subunit. Cell death ultimately occurs by necrosis, not apoptosis. The transcriptomic profile of A. pleuropneumoniae was determined after contact with the porcine lung epithelial cells by using DNA microarrays. Genes such as tadB and rcpA, members of a putative adhesin locus, and a gene whose product has high homology to the Hsf autotransporter adhesin of Haemophilus influenzae were upregulated, as were the genes pgaBC, involved in biofilm biosynthesis, while capsular polysaccharide-associated genes were downregulated. The in vitro models also proved to be efficient with other swine pathogens, such as Actinobacillus suis, Haemophilus parasuis, and Pasteurella multocida. Our results demonstrate that interactions of A. pleuropneumoniae with host epithelial cells seem to involve complex cross talk which results in regulation of various bacterial genes, including some coding for putative adhesins. Furthermore, our data demonstrate the potential of these in vitro models in studying the host-pathogen interactions of other porcine respiratory tract pathogens. PMID:19139196

  6. Tissue inhibitor of metalloproteinase-1 moderates airway re-epithelialization by regulating matrilysin activity.

    PubMed

    Chen, Peter; McGuire, John K; Hackman, Robert C; Kim, Kyoung-Hee; Black, Roy A; Poindexter, Kurt; Yan, Wei; Liu, Phillip; Chen, Ann J; Parks, William C; Madtes, David K

    2008-05-01

    Obliterative bronchiolitis (OB) is the histopathological finding in chronic lung allograft rejection. Mounting evidence suggests that epithelial damage drives the development of airway fibrosis in OB. Tissue inhibitor of metalloproteinase (TIMP)-1 expression increases in lung allografts and is associated with the onset of allograft rejection. Furthermore, in a mouse model of OB, airway obliteration is reduced in TIMP-1-deficient mice. Matrilysin (matrix metallproteinase-7) is essential for airway epithelial repair and is required for the re-epithelialization of airway wounds by facilitating cell migration; therefore, the goal of this study was to determine whether TIMP-1 inhibits re-epithelialization through matrilysin. We found that TIMP-1 and matrilysin co-localized in the epithelium of human lungs with OB and both co-localized and co-immunoprecipitated in wounded primary airway epithelial cultures. TIMP-1-deficient cultures migrated faster, and epithelial cells spread to a greater extent compared with wild-type cultures. TIMP-1 also inhibited matrilysin-mediated cell migration and spreading in vitro. In vivo, TIMP-1 deficiency enhanced airway re-epithelialization after naphthalene injury. Furthermore, TIMP-1 and matrilysin co-localized in airway epithelial cells adjacent to the wound edge. Our data demonstrate that TIMP-1 interacts with matrix metalloproteinases and regulates matrilysin activity during airway epithelial repair. Furthermore, we speculate that TIMP-1 overexpression restricts airway re-epithelialization by inhibiting matrilysin activity, contributing to a stereotypic injury response that promotes airway fibrosis via bronchiole airway epithelial damage and obliteration.

  7. Tissue Inhibitor of Metalloproteinase-1 Moderates Airway Re-Epithelialization by Regulating Matrilysin Activity

    PubMed Central

    Chen, Peter; McGuire, John K.; Hackman, Robert C.; Kim, Kyoung-Hee; Black, Roy A.; Poindexter, Kurt; Yan, Wei; Liu, Phillip; Chen, Ann J.; Parks, William C.; Madtes, David K.

    2008-01-01

    Obliterative bronchiolitis (OB) is the histopathological finding in chronic lung allograft rejection. Mounting evidence suggests that epithelial damage drives the development of airway fibrosis in OB. Tissue inhibitor of metalloproteinase (TIMP)-1 expression increases in lung allografts and is associated with the onset of allograft rejection. Furthermore, in a mouse model of OB, airway obliteration is reduced in TIMP-1-deficient mice. Matrilysin (matrix metallproteinase-7) is essential for airway epithelial repair and is required for the re-epithelialization of airway wounds by facilitating cell migration; therefore, the goal of this study was to determine whether TIMP-1 inhibits re-epithelialization through matrilysin. We found that TIMP-1 and matrilysin co-localized in the epithelium of human lungs with OB and both co-localized and co-immunoprecipitated in wounded primary airway epithelial cultures. TIMP-1-deficient cultures migrated faster, and epithelial cells spread to a greater extent compared with wild-type cultures. TIMP-1 also inhibited matrilysin-mediated cell migration and spreading in vitro. In vivo, TIMP-1 deficiency enhanced airway re-epithelialization after naphthalene injury. Furthermore, TIMP-1 and matrilysin co-localized in airway epithelial cells adjacent to the wound edge. Our data demonstrate that TIMP-1 interacts with matrix metalloproteinases and regulates matrilysin activity during airway epithelial repair. Furthermore, we speculate that TIMP-1 overexpression restricts airway re-epithelialization by inhibiting matrilysin activity, contributing to a stereotypic injury response that promotes airway fibrosis via bronchiole airway epithelial damage and obliteration. PMID:18385523

  8. Masquerading microbial pathogens: Capsular polysaccharides mimic host-tissue molecules

    PubMed Central

    Cress, Brady F.; Englaender, Jacob A.; He, Wenqin; Kasper, Dennis; Linhardt, Robert J.; Koffas, Mattheos A. G.

    2014-01-01

    Summary Bacterial pathogens bearing capsular polysaccharides identical to mammalian glycans benefit from an additional level of protection from host immune response. The increasing prevalence of antibiotic resistant bacteria portends an impending post-antibiotic age, characterized by diminishing efficacy of common antibiotics and routine application of multifaceted, complementary therapeutic approaches to treat bacterial infections, particularly multidrug-resistant organisms. The first line of defense for most bacterial pathogens consists of a physical and immunological barrier known as the capsule, commonly composed of a viscous layer of carbohydrates that are covalently bound to the cell wall in Gram-positive bacteria or often to lipids of the outer membrane in many Gram-negative bacteria. Bacterial capsular polysaccharides are a diverse class of high molecular weight polysaccharides contributing to virulence of many human pathogens in the gut, respiratory tree, urinary tract, and other host tissues, by hiding cell-surface components that might otherwise elicit host immune response. This review highlights capsular polysaccharides that are structurally identical or similar to polysaccharides found in mammalian tissues, including polysialic acid and glycosaminoglycan capsules hyaluronan, heparosan, and chondroitin. Such non-immunogenic coatings render pathogens insensitive to certain immune responses, effectively increasing residence time in host tissues and enabling pathologically relevant population densities to be reached. Biosynthetic pathways and capsular involvement in immune system evasion are described providing a basis for potential therapies aimed at supplementing or replacing antibiotic treatment. PMID:24372337

  9. Host epithelial-viral interactions as cause and cure for asthma.

    PubMed

    Holtzman, Michael J; Patel, Dhara A; Zhang, Yong; Patel, Anand C

    2011-08-01

    Research on the pathogenesis of asthma has concentrated on initial stimuli, genetic susceptibilities, adaptive immune responses, and end-organ alterations (particularly in airway mucous cells and smooth muscle) as critical steps leading to disease. Recent evidence indicates that the innate immune cell response to respiratory viruses also contributes to the development of inflammatory airway disease. We further develop this concept by raising the issue that the interaction between host airway epithelial cells and respiratory viruses is another aspect of innate immunity that is also a critical determinant of asthma. We also introduce a rationale for how antiviral performance at the epithelial cell level might be improved to prevent acute infectious illness and chronic inflammatory disease caused by respiratory viruses. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Mechanisms of Disease: Host-Pathogen Interactions between Burkholderia Species and Lung Epithelial Cells

    PubMed Central

    David, Jonathan; Bell, Rachel E.; Clark, Graeme C.

    2015-01-01

    Members of the Burkholderia species can cause a range of severe, often fatal, respiratory diseases. A variety of in vitro models of infection have been developed in an attempt to elucidate the mechanism by which Burkholderia spp. gain entry to and interact with the body. The majority of studies have tended to focus on the interaction of bacteria with phagocytic cells with a paucity of information available with regard to the lung epithelium. However, the lung epithelium is becoming more widely recognized as an important player in innate immunity and the early response to infections. Here we review the complex relationship between Burkholderia species and epithelial cells with an emphasis on the most pathogenic species, Burkholderia pseudomallei and Burkholderia mallei. The current gaps in knowledge in our understanding are highlighted along with the epithelial host-pathogen interactions that offer potential opportunities for therapeutic intervention. PMID:26636042

  11. Phylogeographic origin of Helicobacter pylori determines host-adaptive responses upon coculture with gastric epithelial cells.

    PubMed

    Sheh, Alexander; Chaturvedi, Rupesh; Merrell, D Scott; Correa, Pelayo; Wilson, Keith T; Fox, James G

    2013-07-01

    While Helicobacter pylori infects over 50% of the world's population, the mechanisms involved in the development of gastric disease are not fully understood. Bacterial, host, and environmental factors play a role in disease outcome. To investigate the role of bacterial factors in H. pylori pathogenesis, global gene expression of six H. pylori isolates was analyzed during coculture with gastric epithelial cells. Clustering analysis of six Colombian clinical isolates from a region with low gastric cancer risk and a region with high gastric cancer risk segregated strains based on their phylogeographic origin. One hundred forty-six genes had increased expression in European strains, while 350 genes had increased expression in African strains. Differential expression was observed in genes associated with motility, pathogenicity, and other adaptations to the host environment. European strains had greater expression of the virulence factors cagA, vacA, and babB and were associated with increased gastric histologic lesions in patients. In AGS cells, European strains promoted significantly higher interleukin-8 (IL-8) expression than did African strains. African strains significantly induced apoptosis, whereas only one European strain significantly induced apoptosis. Our data suggest that gene expression profiles of clinical isolates can discriminate strains by phylogeographic origin and that these profiles are associated with changes in expression of the proinflammatory and protumorigenic cytokine IL-8 and levels of apoptosis in host epithelial cells. These findings support the hypothesis that bacterial factors determined by the phylogeographic origin of H. pylori strains may promote increased gastric disease.

  12. Determining optical properties of epithelial tissues with an obliquely incident beam

    NASA Astrophysics Data System (ADS)

    Rohde, Shelley B.; Kim, Arnold D.

    2015-07-01

    We present a technique for determining the scattering coefficient of epithelial tissue from diffuse reflectance measurements due to an obliquely incident Gaussian beam. This method applies the convolution form of the diffuse reflectance as determined by the corrected diffusion approximation.

  13. Free-floating epithelial micro-tissue arrays: a low cost and versatile technique.

    PubMed

    Flood, P; Alvarez, L; Reynaud, E G

    2016-10-11

    Three-dimensional (3D) tissue models are invaluable tools that can closely reflect the in vivo physiological environment. However, they are usually difficult to develop, have a low throughput and are often costly; limiting their utility to most laboratories. The recent availability of inexpensive additive manufacturing printers and open source 3D design software offers us the possibility to easily create affordable 3D cell culture platforms. To demonstrate this, we established a simple, inexpensive and robust method for producing arrays of free-floating epithelial micro-tissues. Using a combination of 3D computer aided design and 3D printing, hydrogel micro-moulding and collagen cell encapsulation we engineered microenvironments that consistently direct the growth of micro-tissue arrays. We described the adaptability of this technique by testing several immortalised epithelial cell lines (MDCK, A549, Caco-2) and by generating branching morphology and micron to millimetre scaled micro-tissues. We established by fluorescence and electron microscopy that micro-tissues are polarised, have cell type specific differentiated phenotypes and regain native in vivo tissue qualities. Finally, using Salmonella typhimurium we show micro-tissues display a more physiologically relevant infection response compared to epithelial monolayers grown on permeable filter supports. In summary, we have developed a robust and adaptable technique for producing arrays of epithelial micro-tissues. This in vitro model has the potential to be a valuable tool for studying epithelial cell and tissue function/architecture in a physiologically relevant context.

  14. Carcinoma cells misuse the host tissue damage response to invade the brain

    PubMed Central

    Chuang, Han-Ning; van Rossum, Denise; Sieger, Dirk; Siam, Laila; Klemm, Florian; Bleckmann, Annalen; Bayerlová, Michaela; Farhat, Katja; Scheffel, Jörg; Schulz, Matthias; Dehghani, Faramarz; Stadelmann, Christine; Hanisch, Uwe-Karsten; Binder, Claudia; Pukrop, Tobias

    2013-01-01

    The metastatic colonization of the brain by carcinoma cells is still barely understood, in particular when considering interactions with the host tissue. The colonization comes with a substantial destruction of the surrounding host tissue. This leads to activation of damage responses by resident innate immune cells to protect, repair, and organize the wound healing, but may distract from tumoricidal actions. We recently demonstrated that microglia, innate immune cells of the CNS, assist carcinoma cell invasion. Here we report that this is a fatal side effect of a physiological damage response of the brain tissue. In a brain slice coculture model, contact with both benign and malignant epithelial cells induced a response by microglia and astrocytes comparable to that seen at the interface of human cerebral metastases. While the glial damage response intended to protect the brain from intrusion of benign epithelial cells by inducing apoptosis, it proved ineffective against various malignant cell types. They did not undergo apoptosis and actually exploited the local tissue reaction to invade instead. Gene expression and functional analyses revealed that the C-X-C chemokine receptor type 4 (CXCR4) and WNT signaling were involved in this process. Furthermore, CXCR4-regulated microglia were recruited to sites of brain injury in a zebrafish model and CXCR4 was expressed in human stroke patients, suggesting a conserved role in damage responses to various types of brain injuries. Together, our findings point to a detrimental misuse of the glial damage response program by carcinoma cells resistant to glia-induced apoptosis. PMID:23832647

  15. Morselized Amniotic Membrane Tissue for Refractory Corneal Epithelial Defects in Cicatricial Ocular Surface Diseases

    PubMed Central

    Cheng, Anny M. S.; Chua, Lorraine; Casas, Victoria; Tseng, Scheffer C. G.

    2016-01-01

    Purpose To evaluate the clinical efficacy of morselized amniotic membrane and umbilical cord tissue (MAU) in treating refractory corneal epithelial defect in ocular cicatricial diseases. Methods Retrospective review of four patients with ocular cicatricial diseases treated with topical MAU for corneal epithelial defects refractory to conventional treatments including topical lubricants, autologous serum, bandage contact lens, and tarsorraphy. Their symptoms, corneal staining, conjunctival inflammation, and visual acuity were compared before and after treatment. Results After topical application of MAU twice daily, two patients demonstrated rapid corneal epithelialization with prompt visual acuity improvement at the first day. All patients showed corneal epithelialization in 7.3 ± 2.6 days accompanied by a significant relief of symptoms, reduction of ocular surface inflammation, and improvement of visual acuity. Conclusion This pilot study suggests topical MAU can be developed into a novel treatment for treating refractory corneal epithelial defects. Translational Relevance Topical MAU can be an effective novel treatment for refractory corneal epithelial defects. PMID:27226933

  16. The biomechanical properties of an epithelial tissue determine the location of its vasculature

    PubMed Central

    Kragl, Martin; Schubert, Rajib; Karsjens, Haiko; Otter, Silke; Bartosinska, Barbara; Jeruschke, Kay; Weiss, Jürgen; Chen, Chunguang; Alsteens, David; Kuss, Oliver; Speier, Stephan; Eberhard, Daniel; Müller, Daniel J.; Lammert, Eckhard

    2016-01-01

    An important question is how growing tissues establish a blood vessel network. Here we study vascular network formation in pancreatic islets, endocrine tissues derived from pancreatic epithelium. We find that depletion of integrin-linked kinase (ILK) in the pancreatic epithelial cells of mice results in glucose intolerance due to a loss of the intra-islet vasculature. In turn, blood vessels accumulate at the islet periphery. Neither alterations in endothelial cell proliferation, apoptosis, morphology, Vegfa expression and VEGF-A secretion nor ‘empty sleeves' of vascular basement membrane are found. Instead, biophysical experiments reveal that the biomechanical properties of pancreatic islet cells, such as their actomyosin-mediated cortex tension and adhesive forces to endothelial cells, are significantly changed. These results suggest that a sorting event is driving the segregation of endothelial and epithelial cells and indicate that the epithelial biomechanical properties determine whether the blood vasculature invades or envelops a growing epithelial tissue. PMID:27995929

  17. Microbiota-host interplay at the gut epithelial level, health and nutrition.

    PubMed

    Lallès, Jean-Paul

    2016-01-01

    Growing evidence suggests the implication of the gut microbiota in various facets of health and disease. In this review, the focus is put on microbiota-host molecular cross-talk at the gut epithelial level with special emphasis on two defense systems: intestinal alkaline phosphatase (IAP) and inducible heat shock proteins (iHSPs). Both IAP and iHSPs are induced by various microbial structural components (e.g. lipopolysaccharide, flagellin, CpG DNA motifs), metabolites (e.g. n-butyrate) or secreted signal molecules (e.g., toxins, various peptides, polyphosphate). IAP is produced in the small intestine and secreted into the lumen and in the interior milieu. It detoxifies microbial components by dephosphorylation and, therefore, down-regulates microbe-induced inflammation mainly by inhibiting NF-κB pro-inflammatory pathway in enterocytes. IAP gene expression and enzyme activity are influenced by the gut microbiota. Conversely, IAP controls gut microbiota composition both directly, and indirectly though the detoxification of pro-inflammatory free luminal adenosine triphosphate and inflammation inhibition. Inducible HSPs are expressed by gut epithelial cells in proportion to the microbial load along the gastro-intestinal tract. They are also induced by various microbial components, metabolites and secreted molecules. Whether iHSPs contribute to shape the gut microbiota is presently unknown. Both systems display strong anti-inflammatory and anti-oxidant properties that are protective to the gut and the host. Importantly, epithelial gene expressions and protein concentrations of IAP and iHSPs can be stimulated by probiotics, prebiotics and a large variety of dietary components, including macronutrients (protein and amino acids, especially L-glutamine, fat, fiber), and specific minerals (e.g. calcium) and vitamins (e.g. vitamins K1 and K2). Some food components (e.g. lectins, soybean proteins, various polyphenols) may inhibit or disturb these systems. The general cellular

  18. Paramyxovirus Infection Mimics In Vivo Cellular Dynamics in Three-Demensional Human Bronchio-Epithelial Tissue-Like Assemblies

    NASA Technical Reports Server (NTRS)

    Deatly, Anne M.; Lin, Yen-Huei; McCarthy, Maureen; Chen, Wei; Miller, Lynn Z.; Quiroz, Jorge; Nowak, Becky M.; Lerch, Robert A.; Udem, Stephen A.; Goodwin, Thomas J.

    2012-01-01

    , cotton rat, guinea pig, ferret, and hamster) fail to accurately imitate viral replication and human disease states (8). Lacking an authentic model has impeded the development and evaluation of live, attenuated vaccine candidates. Development of a physiologically relevant in vitro tissue culture model that reproduces characteristics of the HRE, the primary target of RSV and PIV3, would aid in predicting clinical attenuation and safety of vaccine candidates. Successful tissue engineering of a 3D human intestinal model using novel NASA technology inspired the development of a tri-culture 3D model for the HRE. Sequential layering of primary mesenchymal cells (comprised of normal human fibroblasts and endothelial cells) followed by BEAS-2B epithelial cells derived from human bronchi and tracheae were recapitulated on Cultisphere and/or cytodex3 microcarriers in cylindrical vessels that rotate horizontally creating an organized epithelial structure. Horizontal rotation randomizes the gravity vector modeling aspects of microgravity. Mesenchymal and epithelial cells grown under these conditions reproduce the structural organization, multi-cellular complexity, and differentiation state of the HRE. The opportunity to study respiratory viruses in a nasal epithelium model is invaluable because the most promising respiratory virus vaccine candidates are live attenuated viruses for intranasal administration. Here we characterize the interactions of respiratory viruses and epithelial cells grown under modeled microgravity in comparison to gravity-ladened monolayers. 3D HBE TLAs and traditional monolayers (2D) are infected at 35 C, the upper temperature of the upper HRE, to simulate in vivo infection conditions. Growth kinetics of wild type (wt) RSV and PIV3 viruses were compared in 2D and 3D cells to that of strains attenuated in humans or rhesus macaques. This novel 3D HBE model also offers an opportunity to study whether the epithelial cell function, especially in host defenses

  19. Activated alveolar epithelial cells initiate fibrosis through autocrine and paracrine secretion of connective tissue growth factor.

    PubMed

    Yang, Jibing; Velikoff, Miranda; Canalis, Ernesto; Horowitz, Jeffrey C; Kim, Kevin K

    2014-04-15

    Fibrogenesis involves a pathological accumulation of activated fibroblasts and extensive matrix remodeling. Profibrotic cytokines, such as TGF-β, stimulate fibroblasts to overexpress fibrotic matrix proteins and induce further expression of profibrotic cytokines, resulting in progressive fibrosis. Connective tissue growth factor (CTGF) is a profibrotic cytokine that is indicative of fibroblast activation. Epithelial cells are abundant in the normal lung, but their contribution to fibrogenesis remains poorly defined. Profibrotic cytokines may activate epithelial cells with protein expression and functions that overlap with the functions of active fibroblasts. We found that alveolar epithelial cells undergoing TGF-β-mediated mesenchymal transition in vitro were also capable of activating lung fibroblasts through production of CTGF. Alveolar epithelial cell expression of CTGF was dramatically reduced by inhibition of Rho signaling. CTGF reporter mice demonstrated increased CTGF promoter activity by lung epithelial cells acutely after bleomycin in vivo. Furthermore, mice with lung epithelial cell-specific deletion of CTGF had an attenuated fibrotic response to bleomycin. These studies provide direct evidence that epithelial cell activation initiates a cycle of fibrogenic effector cell activation during progressive fibrosis. Therapy targeted at epithelial cell production of CTGF offers a novel pathway for abrogating this progressive cycle and limiting tissue fibrosis.

  20. Salmonella Typhimurium Enzymatically Landscapes the Host Intestinal Epithelial Cell (IEC) Surface Glycome to Increase Invasion.

    PubMed

    Park, Dayoung; Arabyan, Narine; Williams, Cynthia C; Song, Ting; Mitra, Anupam; Weimer, Bart C; Maverakis, Emanual; Lebrilla, Carlito B

    2016-12-01

    Although gut host-pathogen interactions are glycan-mediated processes, few details are known about the participating structures. Here we employ high-resolution mass spectrometric profiling to comprehensively identify and quantitatively measure the exact modifications of native intestinal epithelial cell surface N-glycans induced by S. typhimurium infection. Sixty minutes postinfection, select sialylated structures showed decreases in terms of total number and abundances. To assess the effect of cell surface mannosylation, we selectively rerouted glycan expression on the host using the alpha-mannosidase inhibitor, kifunensine, toward overexpression of high mannose. Under these conditions, internalization of S. typhimurium significantly increased, demonstrating that bacteria show preference for particular structures. Finally, we developed a novel assay to measure membrane glycoprotein turnover rates, which revealed that glycan modifications occur by bacterial enzyme activity rather than by host-derived restructuring strategies. This study is the first to provide precise structural information on how host N-glycans are altered to support S. typhimurium invasion. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. In vitro isolation and cultivation of rabbit tracheal epithelial cells using tissue explant technique.

    PubMed

    Shi, Hong-Can; Lu, Dan; Li, Hai-Jia; Han, Shi; Zeng, Yan-Jun

    2013-04-01

    Epithelial cells from tracheal mucosa offer significant potential as a cell source in development of tissue-engineered trachea. The purpose of this study was to investigate and optimize a suitable culture system for tracheal epithelial cells, including the methods of primary culture, passage, identification, and cryopreservation. Epithelial cells were isolated from rabbit tracheal mucosa using tissue explant technique and were subjected to immunohistochemistry, immunofluorescence, and cryopreservation after purification. Epithelial cells reached confluency at 14-15 d. Immunohistochemical staining for cytokeratin showed brown yellow-positive cytoplasm and blue-counterstained nuclei, while immunofluorescence staining for cytokeratin showed green-positive cytoplasm and clear cell outline, indicating that the cultured cells had properties of epithelial cells. After recovery, epithelial cells exhibited high survival and viability. The results demonstrated that in vitro isolation and cultivation model was successfully established to provide high proliferative capacity, typical morphology and characteristics of tracheal epithelial cells from trachea mucosa by the use of the tissue explant technique.

  2. Analysis of CUL-5 expression in breast epithelial cells, breast cancer cell lines, normal tissues and tumor tissues

    PubMed Central

    Fay, Michael J; Longo, Kenneth A; Karathanasis, George A; Shope, David M; Mandernach, Craig J; Leong, Jason R; Hicks, Alfred; Pherson, Kenneth; Husain, Amyna

    2003-01-01

    Background The chromosomal location of CUL-5 (11q 22-23) is associated with LOH in breast cancer, suggesting that CUL-5 may be a tumor suppressor. The purpose of this research was to determine if there is differential expression of CUL-5 in breast epithelial cells versus breast cancer cell lines, and normal human tissues versus human tumors. The expression of CUL-5 in breast epithelial cells (HMEC, MCF-10A), and breast cancer cells (MCF-7, MDA-MB-231) was examined using RT-PCR, Northern blot analysis, and Western blot analysis. The expression of mRNA for other CUL family members (CUL-1, -2, -3, -4A, and -4B) in these cells was evaluated by RT-PCR. A normal human tissue expression array and a cancer profiling array were used to examine CUL-5 expression in normal human tissues and matched normal tissues versus tumor tissues, respectively. Results CUL-5 is expressed at the mRNA and protein levels by breast epithelial cells (HMEC, MCF-10A) and breast cancer cells (MCF-7, MDA-MB-231). These cells also express mRNA for other CUL family members. The normal human tissue expression array revealed that CUL-5 is widely expressed. The cancer profiling array revealed that 82% (41/50) of the breast cancers demonstrated a decrease in CUL-5 expression versus the matched normal tissue. For the 50 cases of matched breast tissue there was a statistically significant ~2.2 fold decreased expression of CUL-5 in tumor tissue versus normal tissue (P < 0.0001). Conclusions The data demonstrate no apparent decrease in CUL-5 expression in the breast cancer cell lines (MCF-7, MDA-MB-231) versus the breast epithelial cells (HMEC, MCF-10A). The decrease in CUL-5 expression in breast tumor tissue versus matched normal tissue supports the hypothesis that decreased expression of CUL-5 may play a role in breast tumorigenesis. PMID:14641918

  3. Host Responses and Regulation by NFκB Signaling in the Liver and Liver Epithelial Cells Infected with A Novel Tick-borne Bunyavirus

    PubMed Central

    Sun, Qiyu; Jin, Cong; Zhu, Lili; Liang, Mifang; Li, Chuan; Cardona, Carol J.; Li, Dexin; Xing, Zheng

    2015-01-01

    Infection in humans by severe fever with thrombocytopenia syndrome virus (SFTSV), a novel bunyavirus transmitted by ticks, is often associated with pronounced liver damage, especially in fatal cases. Little has been known, however, about how liver cells respond to SFTSV and how the response is regulated. In this study we report that proinflammatory cytokines were induced in liver tissues of C57/BL6 mice infected with SFTSV, which may cause tissue necrosis in mice. Human liver epithelial cells were susceptible to SFTSV and antiviral interferon (IFN) and IFN-inducible proteins were induced upon infection. We observed that infection of liver epithelial cells led to significant increases in proinflammatory cytokines and chemokines, including IL-6, RANTES, IP-10, and MIP-3a, which were regulated by NFκB signaling, and the activation of NFκB signaling during infection promoted viral replication in liver epithelial cells. Viral nonstructural protein NSs was inhibitory to the induction of IFN-β, but interestingly, NFκB activation was enhanced in the presence of NSs. Therefore, NSs plays dual roles in the suppression of antiviral IFN-β induction as well as the promotion of proinflammatory responses. Our findings provide the first evidence for elucidating host responses and regulation in liver epithelial cells infected by an emerging bunyavirus. PMID:26134299

  4. A method for establishing human primary gastric epithelial cell culture from fresh surgical gastric tissues.

    PubMed

    Aziz, Faisal; Yang, Xuesong; Wen, Qingping; Yan, Qiu

    2015-08-01

    At present, biopsy specimens, cancer cell lines and tissues obtained by gastric surgery are used in the study and analysis of gastric cancer, including the molecular mechanisms and proteomics. However, fibroblasts and other tissue components may interfere with these techniques. Therefore, the present study aimed to develop a procedure for the isolation of viable human gastric epithelial cells from gastric surgical tissues. A method was developed to culture human gastric epithelial cells using fresh, surgically excised tissues and was evaluated using immunocytochemistry, periodic acid-Schiff (PAS) staining and cell viability assays. Low cell growth was observed surrounding the gastric tissue on the seventh day of tissue explant culture. Cell growth subsequently increased, and at 12 days post-explant a high number of pure epithelial cells were detected. The gastric cancer cells exhibited rapid growth with a doubling time of 13-52 h, as compared to normal cells, which had a doubling time of 20-53 h. Immunocytochemical analyses of primary gastric cells revealed positive staining for cytokeratin 18 and 19, which indicated that the culture was comprised of pure epithelial cells and contained no fibroblasts. Furthermore, PAS staining demonstrated that the cultured gastric cells produced neutral mucin. Granulin and carbohydrate antigen 724 staining confirmed the purity of gastric cancer and normal cells in culture. This method of cell culture indicated that the gastric cells in primary culture consisted of mucin-secreting gastric epithelial cells, which may be useful for the study of gastric infection with Helicobacter pylori and gastric cancer.

  5. Lead, selenium and nickel concentrations in epithelial ovarian cancer, borderline ovarian tumor and healthy ovarian tissues.

    PubMed

    Canaz, Emel; Kilinc, Metin; Sayar, Hamide; Kiran, Gurkan; Ozyurek, Eser

    2017-09-01

    Wide variation exists in ovarian cancer incidence rates suggesting the importance of environmental factors. Due to increasing environmental pollution, trace elements and heavy metals have drawn attention in studies defining the etiology of cancer, but scant data is available for ovarian cancer. Our aim was to compare the tissue concentrations of lead, selenium and nickel in epithelial ovarian cancer, borderline tumor and healthy ovarian tissues. The levels of lead, selenium and nickel were estimated using atomic absorption spectrophotometry in formalin-fixed paraffin-embedded tissue samples. Tests were carried out in 20 malignant epithelial ovarian cancer, 15 epithelial borderline tumor and 20 non-neoplastic healthy ovaries. Two samples were collected for borderline tumors, one from papillary projection and one from the smooth surface of cyst wall. Pb and Ni concentrations were found to be higher both in malignant and borderline tissues than those in healthy ovaries. Concentrations of Pb and Ni in malignant tissues, borderline papillary projections and capsular tissue samples were not different. Comparison of Se concentrations of malignant, borderline and healthy ovarian tissues did not reveal statistical difference. Studied metal levels were not found to be different in either papillary projection or in cyst wall of the borderline tumors. This study revealed the accumulation of lead and nickel in ovarian tissue is associated with borderline and malignant proliferation of the surface epithelium. Accumulation of these metals in epithelial ovarian cancer and borderline ovarian tumor has not been demonstrated before. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Limbal Stromal Tissue Specific Stem Cells and Their Differentiation Potential to Corneal Epithelial Cells.

    PubMed

    Katikireddy, Kishore Reddy; Jurkunas, Ula V

    2016-01-01

    From the derivation of the first human embryonic stem (hES) cell line to the development of induced pluripotent stem (iPS) cells; it has become evident that tissue specific stem cells are able to differentiate into a specific somatic cell types. The understanding of key processes such as the signaling pathways and the role of the microenvironment in epidermal/epithelial development has provided important clues for the derivation of specific epithelial cell types.Various differentiation protocols/methods were used to attain specific epithelial cell types. Here, we describe in detail the procedure to follow for isolation of tissue specific stem cells, mimicking their microenvironment to attain stem cell characteristics, and their potential differentiation to corneal epithelial cells.

  7. A Hybrid Computational Model to Explore the Topological Characteristics of Epithelial Tissues.

    PubMed

    González-Valverde, Ismael; García Aznar, José Manuel

    2017-03-01

    Epithelial tissues show a particular topology where cells resemble a polygon-like shape, but some biological processes can alter this tissue topology. During cell proliferation, mitotic cell dilation deforms the tissue and modifies the tissue topology. Additionally, cells are reorganized in the epithelial layer and these rearrangements also alter the polygon distribution. We present here a computer-based hybrid framework focused on the simulation of epithelial layer dynamics that combines discrete and continuum numerical models. In this framework, we consider topological and mechanical aspects of the epithelial tissue. Individual cells in the tissue are simulated by an off-lattice agent-based model, which keeps the information of each cell. In addition, we model the cell-cell interaction forces and the cell cycle. Otherwise, we simulate the passive mechanical behaviour of the cell monolayer using a material that approximates the mechanical properties of the cell. This continuum approach is solved by the finite element method, which uses a dynamic mesh generated by the triangulation of cell polygons. Forces generated by cell-cell interaction in the agent-based model are also applied on the finite element mesh. Cell movement in the agent-based model is driven by the displacements obtained from the deformed finite element mesh of the continuum mechanical approach. We successfully compare the results of our simulations with some experiments about the topology of proliferating epithelial tissues in Drosophila. Our framework is able to model the emergent behaviour of the cell monolayer that is due to local cell-cell interactions, which have a direct influence on the dynamics of the epithelial tissue.

  8. Genotoxicity of digital panoramic radiography on oral epithelial tissues.

    PubMed

    Sheikh, Soheyl; Pallagatti, Shambulingappa; Grewal, Harshaminder; Kalucha, Aman; Kaur, Harkamal

    2012-09-01

    To evaluate the genotoxic effects of x-rays on gingival and buccal epithelial cells during panoramic dental radiography using the micronucleus test. Eighty otherwise healthy subjects who required a diagnostic panoramic radiograph and met the selection criteria were included in the study. Epithelial cells were obtained from the maxillary anterior gingiva and buccal mucosa by gentle scraping with a wooden spatula immediately before exposure and again 10 days after exposure. Cytologic preparations were made according to the Papanicolaou staining method and analyzed under a light microscope for micronucleus count. The mean ± SD micronucleus count of gingival epithelial cells was 1.08 ± 0.76 before radiographic exposure and 1.6 ± 0.93 after exposure. This increase was statistically significant (P < .05). Similarly, there was an increase in the postexposure micronucleus count in the buccal mucosa, but this increase was not significant (P > .05). A significant correlation was observed between the age of subjects and micronucleus count, although no such correlation was found between sex and micronucleus count. Although radiation-related effects from panoramic radiography were reduced compared with full-mouth intraoral periapical radiographs or radiotherapy, the results of this study show that genotoxic effects do take place. Thus, radiographs should be taken with adequate protection measures and only when the potential benefit outweighs the potential risk.

  9. Burkholderia pseudomallei Differentially Regulates Host Innate Immune Response Genes for Intracellular Survival in Lung Epithelial Cells

    PubMed Central

    Vellasamy, Kumutha Malar; Mariappan, Vanitha; Shankar, Esaki M.; Vadivelu, Jamuna

    2016-01-01

    Background Burkholderia pseudomallei, the causative agent of melioidosis poses a serious threat to humankind. B. pseudomallei secretes numerous virulence proteins that alter host cell functions to escape from intracellular immune sensors. However, the events underlying disease pathogenesis are poorly understood. Methods We determined the ability of B. pseudomallei to invade and survive intracellularly in A549 human lung epithelial cells, and also investigated the early transcriptional responses using an Illumina HumanHT-12 v4 microarray platform, after three hours of exposure to live B. pseudomallei (BCMS) and its secreted proteins (CCMS). Results We found that the ability of B. pseudomallei to invade and survive intracellularly correlated with increase of multiplicity of infection and duration of contact. Activation of host carbohydrate metabolism and apoptosis as well as suppression of amino acid metabolism and innate immune responses both by live bacteria and its secreted proteins were evident. These early events might be linked to initial activation of host genes directed towards bacterial dissemination from lungs to target organs (via proposed in vivo mechanisms) or to escape potential sensing by macrophages. Conclusion Understanding the early responses of A549 cells toward B. pseudomallei infection provide preliminary insights into the likely pathogenesis mechanisms underlying melioidosis, and could contribute to development of novel intervention strategies to combat B. pseudomallei infections. PMID:27367858

  10. Host Tissue and Glycan Binding Specificities of Avian Viral Attachment Proteins Using Novel Avian Tissue Microarrays

    PubMed Central

    Ambepitiya Wickramasinghe, Iresha N.; de Vries, Robert P.; Eggert, Amber M.; Wandee, Nantaporn; de Haan, Cornelis A. M.; Gröne, Andrea; Verheije, Monique H.

    2015-01-01

    The initial interaction between viral attachment proteins and the host cell is a critical determinant for the susceptibility of a host for a particular virus. To increase our understanding of avian pathogens and the susceptibility of poultry species, we developed novel avian tissue microarrays (TMAs). Tissue binding profiles of avian viral attachment proteins were studied by performing histochemistry on multi-species TMA, comprising of selected tissues from ten avian species, and single-species TMAs, grouping organ systems of each species together. The attachment pattern of the hemagglutinin protein was in line with the reported tropism of influenza virus H5N1, confirming the validity of TMAs in profiling the initial virus-host interaction. The previously believed chicken-specific coronavirus (CoV) M41 spike (S1) protein displayed a broad attachment pattern to respiratory tissues of various avian species, albeit with lower affinity than hemagglutinin, suggesting that other avian species might be susceptible for chicken CoV. When comparing tissue-specific binding patterns of various avian coronaviral S1 proteins on the single-species TMAs, chicken and partridge CoV S1 had predominant affinity for the trachea, while pigeon CoV S1 showed marked preference for lung of their respective hosts. Binding of all coronaviral S1 proteins was dependent on sialic acids; however, while chicken CoV S1 preferred sialic acids type I lactosamine (Gal(1-3)GlcNAc) over type II (Gal(1-4)GlcNAc), the fine glycan specificities of pigeon and partridge CoVs were different, as chicken CoV S1-specific sialylglycopolymers could not block their binding to tissues. Taken together, TMAs provide a novel platform in the field of infectious diseases to allow identification of binding specificities of viral attachment proteins and are helpful to gain insight into the susceptibility of host and organ for avian pathogens. PMID:26035584

  11. SURFACE CHEMISTRY INFLUENCE IMPLANT MEDIATED HOST TISSUE RESPONSES

    PubMed Central

    Kamath, Shwetha; Bhattacharyya, Dhiman; Padukudru, Chandana; Timmons, Richard B.; Tang, Liping

    2011-01-01

    Implant-mediated fibrotic reactions are detrimental to the performance of encapsulated cells, implanted drug release devices and sensors. To improve the implant function and longevity, research has emphasized altering cellular responses. Although material surface functional groups have been shown to be potent in affecting cellular activity in vitro and short term in vivo responses, these groups appear to have little influence on long-term in vivo fibrotic reactions, possibly as a result of insufficient interactions between recruited host cells and functional groups on the implants. To maximize the influence of functionality on cells, and to mimic drug release microspheres, functionalized micron-sized particles were created and tested for their ability in modulating tissue responses to biomaterial implants. In this work, the surfaces of polypropylene particles were controllably coated with four different functional groups, specifically –OH, -NH2, -CFx and –COOH, using a radio frequency glow discharge plasma polymerization technique. The effect of these surface functionalities on host tissue responses were then evaluated using a mice subcutaneous implantation model. Major differences were observed in contrasting tissue response to the different chemistries. Surfaces with –OH and –NH2 surface groups induced the thickest fibrous capsule accompanied with the greatest cellular infiltration into the implants. In contrast, surfaces with –CFx and –COOH exhibited the least inflammatory/fibrotic responses and cellular infiltrations. The present results clearly demonstrate that, by increasing the available functionalized surface area and spatial distribution, the effect of surface chemistry on tissue reactivity can be substantially enhanced. PMID:18022841

  12. Epithelial-connective tissue boundary in the oral part of the human soft palate

    PubMed Central

    PAULSEN, FRIEDRICH; THALE, ANDREAS

    1998-01-01

    The papillary layer of the oral part of the human soft palate was studied in 31 subjects of different age by means of histological, immunohistochemical and scanning electron microscopical methods. For scanning electron microscopy a new maceration method was introduced. Results determine epithelial thickness, height and density of connective tissue papillae and their 3-dimensional architecture inside the lining epithelium as well as the collagenous arrangement of the openings of the glandular ducts. The individual connective tissue papillae of the soft palate are compared with the connective tissue boundary on the other side of the oral cavity. The connective tissue plateaux carrying a variable number of connective tissue papillae were found to be the basic structural units of the papillary body. The function of the epithelial-connective tissue interface and the extracellular matrix arrangement in the lamina propria are discussed in order to promote the comparability of normal with pathologically altered human soft palates. PMID:9877301

  13. CONTRIBUTION OF HOST-DERIVED TISSUE FACTOR TO TUMOR NEOVASCULARIZATION

    PubMed Central

    Yu, Joanne; May, Linda; Milsom, Chloe; Anderson, G. Mark; Weitz, Jeffrey I.; Luyendyk, James P.; Broze, George; Mackman, Nigel; Rak, Janusz

    2010-01-01

    Objective The role of host-derived tissue factor (TF) in tumor growth, angiogenesis and metastasis has hitherto been unclear, and was investigated in this study. Methods We compared tumor growth, vascularity and responses to cyclophosphamide (CTX) of tumors in wild type (wt) mice, or in animals with TF levels reduced by 99% (low-TF mice). Results Global growth rate of three different types of transplantable tumors (LLC, B16F1 and ES teratoma), or metastasis were unchanged in low-TF mice. However, several unexpected tumor/context-specific alterations were observed in these mice, including: (i) reduced tumor blood vessel size in B16F1 tumors; (ii) larger spleen size and greater tolerance to CTX toxicity in the LLC model; (iii) aborted tumor growth after inoculation of TF-deficient tumor cells (ES TF-/-) in low-TF mice. TF-deficient tumor cells grew readily in mice with normal TF levels, and attracted exclusively host-related blood vessels (without vasculogenic mimicry). We postulate that this complementarity may result from tumor-vascular transfer of TF-containing microvesicles, as we observed such transfer using human cancer cells (A431) and mouse endothelial cells, both in vitro and in vivo. Conclusions Our study points to an important, but context-dependent role of host TF in tumor formation, angiogenesis and therapy. PMID:18772494

  14. Normal human epithelial cells regulate the size and morphology of tissue-engineered capillaries.

    PubMed

    Rochon, Marie-Hélène; Fradette, Julie; Fortin, Véronique; Tomasetig, Florence; Roberge, Charles J; Baker, Kathleen; Berthod, François; Auger, François A; Germain, Lucie

    2010-05-01

    The survival of thick tissues/organs produced by tissue engineering requires rapid revascularization after grafting. Although capillary-like structures have been reconstituted in some engineered tissues, little is known about the interaction between normal epithelial cells and endothelial cells involved in the in vitro angiogenic process. In the present study, we used the self-assembly approach of tissue engineering to examine this relationship. An endothelialized tissue-engineered dermal substitute was produced by adding endothelial cells to the tissue-engineered dermal substitute produced by the self-assembly approach. The latter consists in culturing fibroblasts in the medium supplemented with serum and ascorbic acid. A network of tissue-engineered capillaries (TECs) formed within the human extracellular matrix produced by dermal fibroblasts. To determine whether epithelial cells modify TECs, the size and form of TECs were studied in the endothelialized tissue-engineered dermal substitute cultured in the presence or absence of epithelial cells. In the presence of normal keratinocytes from skin, cornea or uterine cervix, endothelial cells formed small TECs (cross-sectional area estimated at less than 50 microm(2)) reminiscent of capillaries found in the skin's microcirculation. In contrast, TECs grown in the absence of epithelial cells presented variable sizes (larger than 50 microm(2)), but the addition of keratinocyte-conditioned media or exogenous vascular endothelial growth factor induced their normalization toward a smaller size. Vascular endothelial growth factor neutralization inhibited the effect of keratinocyte-conditioned media. These results provide new direct evidence that normal human epithelial cells play a role in the regulation of the underlying TEC network, and advance our knowledge in tissue engineering for the production of TEC networks in vitro.

  15. Screening of the residual normal ovarian tissue adjacent to orthotopic epithelial ovarian carcinomas in nude mice.

    PubMed

    Zhu, G H; Wang, S T; Yao, M Z; Cai, J H; Chen, C Y; Yang, Z X; Hong, L; Yang, S Y

    2014-04-16

    The objective of this study was to explore the feasibility and methods of screening the residual normal ovarian tissue adjacent to orthotopic ovarian carcinomas in nude mice. Human epithelial ovarian cancer cells (OVCAR3) were subcutaneously implanted for a tumor source and ovarian orthotopic transplantation. The cancer tissue, proximal paraneoplastic tissue, middle paraneoplastic tissue, remote paraneoplastic tissue, and normal ovarian tissue were removed. CK-7, CA125, p53, survivin, MMP-2, and TIMP-2 expression was detected by reverse transcription polymerase chain reaction. We obtained 35 paraneoplastic residual ovarian tissues with normal biopsies from 40 cases of an orthotopic epithelial ovarian carcinoma model (87.5%). CK-7, CA125, p53, survivin, MMP-2, and TIMP-2 expression was lower in proximal paraneoplastic tissue than in cancer tissue (P < 0.05) and higher than in middle and remote paraneoplastic tissue (P < 0.01). There was no statistically significant difference between the expression of these genes in middle and proximal paraneoplastic tissue as well as among residual normal ovarian tissues with different severity (P > 0.05). In ovarian tissues of 20 normal nude mice, the expression of CK- 7, CA125, p53, survivin, MMP-2, and TIMP-2 was negative. Overall, the expression levels of CK-7, CA125, p53, survivin, MMP-2, TIMP-2, and other molecular markers showed a decreasing trend in the non-cancer tissue direction. The expression levels can be used as standards to screen residual normal ovarian tissue. We can obtain relatively safe normal ovarian tissues adjacent to epithelial ovarian cancer.

  16. Development of transplanted pulp tissue containing epithelial sheath into a tooth-like structure.

    PubMed

    Lyaruu, D M; van Croonenburg, E J; van Duin, M A; Bervoets, T J; Wöltgens, J H; de Blieck-Hogervorst, J M

    1999-08-01

    The aim of these studies was to find out whether intact neonatal pulp tissue containing residual epithelial cells can induce the development of a tooth-like structure in situ. First maxillary neonatal hamster molar pulps containing adhering undifferentiated epithelial cells were transplanted submucosally in the oral cavity of recipient mothers for periods ranging from 2-8 weeks and the tissues were then processed for light microscopy. Developing tooth-like structures containing mineralised tubular dentine, predentine and a vascularised pulp-like chamber lined with functional odontoblast-like cells were observed in the specimens within 2 weeks of transplantation. Enamel and root formation were not observed. These data indicate that neonatal dental pulp tissues containing epithelial cell remnants have the capacity to develop into tooth-like structures and that this could be the explanation for the development of tooth-like structures sometimes observed in infants after extraction of a natal tooth.

  17. Advanced imaging and tissue engineering of the human limbal epithelial stem cell niche.

    PubMed

    Massie, Isobel; Dziasko, Marc; Kureshi, Alvena; Levis, Hannah J; Morgan, Louise; Neale, Michael; Sheth, Radhika; Tovell, Victoria E; Vernon, Amanda J; Funderburgh, James L; Daniels, Julie T

    2015-01-01

    The limbal epithelial stem cell niche provides a unique, physically protective environment in which limbal epithelial stem cells reside in close proximity with accessory cell types and their secreted factors. The use of advanced imaging techniques is described to visualize the niche in three dimensions in native human corneal tissue. In addition, a protocol is provided for the isolation and culture of three different cell types, including human limbal epithelial stem cells from the limbal niche of human donor tissue. Finally, the process of incorporating these cells within plastic compressed collagen constructs to form a tissue-engineered corneal limbus is described and how immunohistochemical techniques may be applied to characterize cell phenotype therein.

  18. Active Vertex Model for cell-resolution description of epithelial tissue mechanics

    PubMed Central

    Barton, Daniel L.; Henkes, Silke

    2017-01-01

    We introduce an Active Vertex Model (AVM) for cell-resolution studies of the mechanics of confluent epithelial tissues consisting of tens of thousands of cells, with a level of detail inaccessible to similar methods. The AVM combines the Vertex Model for confluent epithelial tissues with active matter dynamics. This introduces a natural description of the cell motion and accounts for motion patterns observed on multiple scales. Furthermore, cell contacts are generated dynamically from positions of cell centres. This not only enables efficient numerical implementation, but provides a natural description of the T1 transition events responsible for local tissue rearrangements. The AVM also includes cell alignment, cell-specific mechanical properties, cell growth, division and apoptosis. In addition, the AVM introduces a flexible, dynamically changing boundary of the epithelial sheet allowing for studies of phenomena such as the fingering instability or wound healing. We illustrate these capabilities with a number of case studies. PMID:28665934

  19. Advanced Imaging and Tissue Engineering of the Human Limbal Epithelial Stem Cell Niche

    PubMed Central

    Massie, Isobel; Dziasko, Marc; Kureshi, Alvena; Levis, Hannah J.; Morgan, Louise; Neale, Michael; Sheth, Radhika; Tovell, Victoria E.; Vernon, Amanda J.; Funderburgh, James L.; Daniels, Julie T.

    2015-01-01

    The limbal epithelial stem cell niche provides a unique, physically protective environment in which limbal epithelial stem cells reside in close proximity with accessory cell types and their secreted factors. The use of advanced imaging techniques is described to visualize the niche in three dimensions in native human corneal tissue. In addition, a protocol is provided for the isolation and culture of three different cell types, including human limbal epithelial stem cells from the limbal niche of human donor tissue. Finally, the process of incorporating these cells within plastic compressed collagen constructs to form a tissue-engineered corneal limbus is described and how immunohistochemical techniques may be applied to characterize cell phenotype therein. PMID:25388395

  20. Oblique polarized reflectance spectroscopy for depth sensitive measurements in the epithelial tissue

    NASA Astrophysics Data System (ADS)

    Jimenez, Maria K.; Fradkin, Leonid; Nieman, Linda T.; Lam, Sylvia; Poh, Catherine; Sokolov, Konstantin

    2013-02-01

    Optical spectroscopy has shown potential as a tool for precancer detection by discriminating alterations in the optical properties within epithelial tissues. Identifying depth-dependent alterations associated with the progression of epithelial cancerous lesions can be especially challenging in the oral cavity due to the variable thickness of the epithelium and the presence of keratinization. Optical spectroscopy of epithelial tissue with improved depth resolution would greatly assist in the isolation of optical properties associated with cancer progression. Here, we report a fiber optic probe for oblique polarized reflectance spectroscopy (OPRS) that is capable of depth sensitive detection by combining the following three approaches: multiple beveled fibers, oblique collection geometry, and polarization gating. We analyze how probe design parameters are related to improvements in collection efficiency of scattered photons from superficial tissue layers and to increased depth discrimination within epithelium. We have demonstrated that obliquely-oriented collection fibers increase both depth selectivity and collection efficiency of scattering signal. Currently, we evaluate this technology in a clinical trial of patients presenting lesions suspicious for dysplasia or carcinoma in the oral cavity. We use depth sensitive spectroscopic data to develop automated algorithms for analysis of morphological and architectural changes in the context of the multilayer oral epithelial tissue. Our initial results show that OPRS has the potential to improve the detection and monitoring of epithelial precancers in the oral cavity.

  1. Type 3 innate lymphoid cells maintain intestinal epithelial stem cells after tissue damage.

    PubMed

    Aparicio-Domingo, Patricia; Romera-Hernandez, Monica; Karrich, Julien J; Cornelissen, Ferry; Papazian, Natalie; Lindenbergh-Kortleve, Dicky J; Butler, James A; Boon, Louis; Coles, Mark C; Samsom, Janneke N; Cupedo, Tom

    2015-10-19

    Disruption of the intestinal epithelial barrier allows bacterial translocation and predisposes to destructive inflammation. To ensure proper barrier composition, crypt-residing stem cells continuously proliferate and replenish all intestinal epithelial cells within days. As a consequence of this high mitotic activity, mucosal surfaces are frequently targeted by anticancer therapies, leading to dose-limiting side effects. The cellular mechanisms that control tissue protection and mucosal healing in response to intestinal damage remain poorly understood. Type 3 innate lymphoid cells (ILC3s) are regulators of homeostasis and tissue responses to infection at mucosal surfaces. We now demonstrate that ILC3s are required for epithelial activation and proliferation in response to small intestinal tissue damage induced by the chemotherapeutic agent methotrexate. Multiple subsets of ILC3s are activated after intestinal tissue damage, and in the absence of ILC3s, epithelial activation is lost, correlating with increased pathology and severe damage to the intestinal crypts. Using ILC3-deficient Lgr5 reporter mice, we show that maintenance of intestinal stem cells after damage is severely impaired in the absence of ILC3s or the ILC3 signature cytokine IL-22. These data unveil a novel function of ILC3s in limiting tissue damage by preserving tissue-specific stem cells.

  2. Maximum imaging depth of two-photon autofluorescence microscopy in epithelial tissues.

    PubMed

    Durr, Nicholas J; Weisspfennig, Christian T; Holfeld, Benjamin A; Ben-Yakar, Adela

    2011-02-01

    Endogenous fluorescence provides morphological, spectral, and lifetime contrast that can indicate disease states in tissues. Previous studies have demonstrated that two-photon autofluorescence microscopy (2PAM) can be used for noninvasive, three-dimensional imaging of epithelial tissues down to approximately 150 μm beneath the skin surface. We report ex-vivo 2PAM images of epithelial tissue from a human tongue biopsy down to 370 μm below the surface. At greater than 320 μm deep, the fluorescence generated outside the focal volume degrades the image contrast to below one. We demonstrate that these imaging depths can be reached with 160 mW of laser power (2-nJ per pulse) from a conventional 80-MHz repetition rate ultrafast laser oscillator. To better understand the maximum imaging depths that we can achieve in epithelial tissues, we studied image contrast as a function of depth in tissue phantoms with a range of relevant optical properties. The phantom data agree well with the estimated contrast decays from time-resolved Monte Carlo simulations and show maximum imaging depths similar to that found in human biopsy results. This work demonstrates that the low staining inhomogeneity (∼ 20) and large scattering coefficient (∼ 10 mm(-1)) associated with conventional 2PAM limit the maximum imaging depth to 3 to 5 mean free scattering lengths deep in epithelial tissue.

  3. Lactobacilli Interfere with Streptococcus pyogenes Hemolytic Activity and Adherence to Host Epithelial Cells

    PubMed Central

    Saroj, Sunil D.; Maudsdotter, Lisa; Tavares, Raquel; Jonsson, Ann-Beth

    2016-01-01

    Streptococcus pyogenes [Group A streptococcus (GAS)], a frequent colonizer of the respiratory tract mucosal surface, causes a variety of human diseases, ranging from pharyngitis to the life-threatening streptococcal toxic shock-like syndrome. Lactobacilli have been demonstrated to colonize the respiratory tract. In this study, we investigated the interference of lactobacilli with the virulence phenotypes of GAS. The Lactobacillus strains L. rhamnosus Kx151A1 and L. reuteri PTA-5289, but not L. salivarius LMG9477, inhibited the hemolytic activity of S. pyogenes S165. The inhibition of hemolytic activity was attributed to a decrease in the production of streptolysin S (SLS). Conditioned medium (CM) from the growth of L. rhamnosus Kx151A1 and L. reuteri PTA-5289 was sufficient to down-regulate the expression of the sag operon, encoding SLS. The Lactobacillus strains L. rhamnosus Kx151A1, L. reuteri PTA-5289, and L. salivarius LMG9477 inhibited the initial adherence of GAS to host epithelial cells. Intriguingly, competition with a combination of Lactobacillus species reduced GAS adherence to host cells most efficiently. The data suggest that an effector molecule released from certain Lactobacillus strains attenuates the production of SLS at the transcriptional level and that combinations of Lactobacillus strains may protect the pharyngeal mucosa more efficiently from the initial colonization of GAS. The effector molecules released from Lactobacillus strains affecting the virulence phenotypes of pathogens hold potential in the development of a new generation of therapeutics. PMID:27524981

  4. Remodeling of the epithelial-connective tissue interface (ECTI) in oral epithelial dysplasia as visualized by noninvasive 3D imaging

    PubMed Central

    Pal, Rahul; Shilagard, Tuya; Yang, Jinping; Villarreal, Paula; Brown, Tyra; Qiu, Suimin; McCammon, Susan; Resto, Vicente; Vargas, Gracie

    2016-01-01

    Early neoplastic features in oral epithelial dysplasia are first evident at the basal epithelium positioned at the epithelial-connective tissue interface (ECTI), separating the basal epithelium from the underlying lamina propria. The ECTI undergoes significant deformation in early neoplasia due to focal epithelial expansion and proteolytic remodeling of the lamina propria but few studies have examined these changes. In the present study, we quantitated alterations in ECTI topography in dysplasia using in vivo volumetric multiphoton autofluorescence microscopy and second harmonic generation microscopy. The label-free method allows direct noninvasive visualization of the ECTI surface without perturbing the epithelium. An image-based parameter, ‘ECTI contour’, is described that indicates deformation of the ECTI surface. ECTI contour was higher in dysplasia than control or inflammed specimens, indicating transition from flat to a deformed surface. Cellular parameters of nuclear area, nuclear density, coefficient of variation in nuclear area in the basal epithelium and collagen density in areas adjacent to ECTI were measured. ECTI contour differentiated dysplasia from control/benign mucosa with higher sensitivity and specificity than basal nuclear density or basal nuclear area, comparable to coefficient of variation in nuclear area and collagen density. The presented method offers a unique opportunity to study ECTI in intact mucosa with simultaneous assessment of cellular and extracellular matrix features, expanding opportunities for studies of early neoplastic events near this critical interface and potentially leading to development of new approaches for detecting neoplasia in vivo. PMID:27302162

  5. Robust cell tracking in epithelial tissues through identification of maximum common subgraphs.

    PubMed

    Kursawe, Jochen; Bardenet, Rémi; Zartman, Jeremiah J; Baker, Ruth E; Fletcher, Alexander G

    2016-11-01

    Tracking of cells in live-imaging microscopy videos of epithelial sheets is a powerful tool for investigating fundamental processes in embryonic development. Characterizing cell growth, proliferation, intercalation and apoptosis in epithelia helps us to understand how morphogenetic processes such as tissue invagination and extension are locally regulated and controlled. Accurate cell tracking requires correctly resolving cells entering or leaving the field of view between frames, cell neighbour exchanges, cell removals and cell divisions. However, current tracking methods for epithelial sheets are not robust to large morphogenetic deformations and require significant manual interventions. Here, we present a novel algorithm for epithelial cell tracking, exploiting the graph-theoretic concept of a 'maximum common subgraph' to track cells between frames of a video. Our algorithm does not require the adjustment of tissue-specific parameters, and scales in sub-quadratic time with tissue size. It does not rely on precise positional information, permitting large cell movements between frames and enabling tracking in datasets acquired at low temporal resolution due to experimental constraints such as phototoxicity. To demonstrate the method, we perform tracking on the Drosophila embryonic epidermis and compare cell-cell rearrangements to previous studies in other tissues. Our implementation is open source and generally applicable to epithelial tissues.

  6. Robust cell tracking in epithelial tissues through identification of maximum common subgraphs

    PubMed Central

    Bardenet, Rémi; Zartman, Jeremiah J.; Baker, Ruth E.

    2016-01-01

    Tracking of cells in live-imaging microscopy videos of epithelial sheets is a powerful tool for investigating fundamental processes in embryonic development. Characterizing cell growth, proliferation, intercalation and apoptosis in epithelia helps us to understand how morphogenetic processes such as tissue invagination and extension are locally regulated and controlled. Accurate cell tracking requires correctly resolving cells entering or leaving the field of view between frames, cell neighbour exchanges, cell removals and cell divisions. However, current tracking methods for epithelial sheets are not robust to large morphogenetic deformations and require significant manual interventions. Here, we present a novel algorithm for epithelial cell tracking, exploiting the graph-theoretic concept of a ‘maximum common subgraph’ to track cells between frames of a video. Our algorithm does not require the adjustment of tissue-specific parameters, and scales in sub-quadratic time with tissue size. It does not rely on precise positional information, permitting large cell movements between frames and enabling tracking in datasets acquired at low temporal resolution due to experimental constraints such as phototoxicity. To demonstrate the method, we perform tracking on the Drosophila embryonic epidermis and compare cell–cell rearrangements to previous studies in other tissues. Our implementation is open source and generally applicable to epithelial tissues. PMID:28334699

  7. Tissue architecture: the ultimate regulator of breast epithelial function

    SciTech Connect

    Bissell, Mina J; Rizki, Aylin; Mian, Saira

    2003-10-20

    A problem in developmental biology that continues to take center stage is how higher organisms generate diverse tissues and organs given the same cellular genotype. In cell and tumor biology, the key question is not the production of form, but its preservation: how do tissues and organs maintain homeostasis, and how do cells within tissues lose or overcome these controls in cancer? Undoubtedly, mechanisms that maintain tissue specificity should share features with those employed to drive formation of the tissues. However, they are unlikely to be identical. At a simplistic level, developmental pathways may be thought of as a series of extremely rapid short-term events. Each new step depends on what came before, and the outcome is the organism itself at birth. All organs, with a few notable exceptions, such as the mammary gland and the brain, 'arrive' together and are complete when the organism is born. In mice and humans, these events occur in a mere 21 days and 9 months respectively. The stability of the differentiated state and the homeostasis of the organism, on the other hand, will last 40-110 times longer. How does the organism achieve this feat? How are tissues maintained? These questions also relate fundamentally to how tissues become malignant and, although not discussed here, to aging. While there is much literature on differentiation - loosely defined as the gain of a single or a series of functions - we know much less about the forces and the pathways that maintain organ morphology and function as a unit. This may be partly because it is difficult to study a tissue as a unit in vivo and there are few techniques that allow maintenance of organs in vitro long enough and in such a way as to make cell and molecular biology experiments possible. Techniques for culturing cells in three-dimensional gels (3D) as a surrogate for tissues, however, have been steadily improving and the method is now used by several laboratories. In this commentary we discuss the

  8. Tissue specificity of epithelial keratins: differential expression of mRNAs from two multigene families.

    PubMed Central

    Kim, K H; Rheinwald, J G; Fuchs, E V

    1983-01-01

    Human epithelial cells cultured from stratified and simple squamous tissues all produce keratins of 40,000 to 58,000 daltons, but within this range the number and sizes vary with different epithelial cells. We have shown that this tissue-specific variation in the keratins is not due to posttranslational modification or processing, but rather to the differential expression of a family of heterogeneous but closely related mRNAs. All of these epithelial keratin mRNAs can be further grouped into two distinct subfamilies by their ability to hybridize with either of two cloned epidermal keratin cDNAs. All of the keratin mRNAs hybridize to one or the other, but not both, of the two cloned cDNAs. However, the mRNAs within each group hybridize with varying degrees of stringency, indicating that they are of similar but not identical sequence. Both types of keratin mRNAs are always expressed in every epithelial cell line studied, suggesting that filament assembly is dependent on the presence of both types of keratins. Within each of these two groups, the slight sequence differences in each class may reflect subtle tissue-specific variations in the structural and functional requirements of the epithelial cytoskeleton. Images PMID:6190074

  9. Cell-size distribution in epithelial tissue formation and homeostasis.

    PubMed

    Puliafito, Alberto; Primo, Luca; Celani, Antonio

    2017-03-01

    How cell growth and proliferation are orchestrated in living tissues to achieve a given biological function is a central problem in biology. During development, tissue regeneration and homeostasis, cell proliferation must be coordinated by spatial cues in order for cells to attain the correct size and shape. Biological tissues also feature a notable homogeneity of cell size, which, in specific cases, represents a physiological need. Here, we study the temporal evolution of the cell-size distribution by applying the theory of kinetic fragmentation to tissue development and homeostasis. Our theory predicts self-similar probability density function (PDF) of cell size and explains how division times and redistribution ensure cell size homogeneity across the tissue. Theoretical predictions and numerical simulations of confluent non-homeostatic tissue cultures show that cell size distribution is self-similar. Our experimental data confirm predictions and reveal that, as assumed in the theory, cell division times scale like a power-law of the cell size. We find that in homeostatic conditions there is a stationary distribution with lognormal tails, consistently with our experimental data. Our theoretical predictions and numerical simulations show that the shape of the PDF depends on how the space inherited by apoptotic cells is redistributed and that apoptotic cell rates might also depend on size. © 2017 The Author(s).

  10. Streptococcus pneumoniae Infection of Host Epithelial Cells via Polymeric Immunoglobulin Receptor Transiently Induces Calcium Release from Intracellular Stores*

    PubMed Central

    Asmat, Tauseef M.; Agarwal, Vaibhav; Räth, Susann; Hildebrandt, Jan-Peter; Hammerschmidt, Sven

    2011-01-01

    The pneumococcal surface protein C (PspC) is a major adhesin of Streptococcus pneumoniae (pneumococci) that interacts in a human-specific manner with the ectodomain of the human polymeric immunoglobulin receptor (pIgR) produced by respiratory epithelial cells. This interaction promotes bacterial colonization and bacterial internalization by initiating host signal transduction cascades. Here, we examined alterations of intracellular calcium ([Ca2+]i) levels in epithelial cells during host cell infections with pneumococci via the PspC-hpIgR mechanism. The release of [Ca2+]i from intracellular stores in host cells was significantly increased by wild-type pneumococci but not by PspC-deficient pneumococci. The increase in [Ca2+]i was dependent on phospholipase C as pretreatment of cells with a phospholipase C-specific inhibitor U73122 abolished the increase in [Ca2+]i. In addition, we demonstrated the effect of [Ca2+]i on pneumococcal internalization by epithelial cells. Uptake of pneumococci was significantly increased after pretreatment of epithelial cells with the cell-permeable calcium chelator 1,2-bis-(o-aminophenoxy)-ethane-N,N,N′,N′-tetraacetic acid-tetraacetoxymethyl ester or use of EGTA as an extracellular Ca2+-chelating agent. In contrast, thapsigargin, an inhibitor of endoplasmic reticulum Ca2+ATPase, which increases [Ca2+]i in a sustained fashion, significantly reduced pIgR-mediated pneumococcal invasion. Importantly, pneumococcal adherence to pIgR-expressing cells was not altered in the presence of inhibitors as demonstrated by immunofluorescence microscopy. In conclusion, these results demonstrate that pneumococcal infections induce mobilization of [Ca2+]i from intracellular stores. This may constitute a defense response of host cells as the experimental reduction of intracellular calcium levels facilitates pneumococcal internalization by pIgR-expressing cells, whereas elevated calcium levels diminished bacterial internalization by host epithelial

  11. Three-dimensional epithelial tissues generated from human embryonic stem cells.

    PubMed

    Hewitt, Kyle J; Shamis, Yulia; Carlson, Mark W; Aberdam, Edith; Aberdam, Daniel; Garlick, Jonathan A

    2009-11-01

    The use of pluripotent human embryonic stem (hES) cells for tissue engineering may provide advantages over traditional sources of progenitor cells because of their ability to give rise to multiple cell types and their unlimited expansion potential. We derived cell populations with properties of ectodermal and mesenchymal cells in two-dimensional culture and incorporated these divergent cell populations into three-dimensional (3D) epithelial tissues. When grown in specific media and substrate conditions, two-dimensional cultures were enriched in cells (EDK1) with mesenchymal morphology and surface markers. Cells with a distinct epithelial morphology (HDE1) that expressed cytokeratin 12 and beta-catenin at cell junctions became the predominant cell type when EDK1 were grown on surfaces enriched in keratinocyte-derived extracellular matrix proteins. When these cells were incorporated into the stromal and epithelial tissue compartments of 3D tissues, they generated multilayer epithelia similar to those generated with foreskin-derived epithelium and fibroblasts. Three-dimensional tissues demonstrated stromal cells with morphologic features of mature fibroblasts, type IV collagen deposition in the basement membrane, and a stratified epithelium that expressed cytokeratin 12. By deriving two distinct cell lineages from a common hES cell source to fabricate complex tissues, it is possible to explore environmental cues that will direct hES-derived cells toward optimal tissue form and function.

  12. Functional imaging and assessment of the glucose diffusion rate in epithelial tissues in optical coherence tomography

    SciTech Connect

    Larin, K V; Tuchin, V V

    2008-06-30

    Functional imaging, monitoring and quantitative description of glucose diffusion in epithelial and underlying stromal tissues in vivo and controlling of the optical properties of tissues are extremely important for many biomedical applications including the development of noninvasive or minimally invasive glucose sensors as well as for therapy and diagnostics of various diseases, such as cancer, diabetic retinopathy, and glaucoma. Recent progress in the development of a noninvasive molecular diffusion biosensor based on optical coherence tomography (OCT) is described. The diffusion of glucose was studied in several epithelial tissues both in vitro and in vivo. Because OCT provides depth-resolved imaging of tissues with high in-depth resolution, the glucose diffusion is described not only as a function of time but also as a function of depth. (special issue devoted to application of laser technologies in biophotonics and biomedical studies)

  13. A method for high purity intestinal epithelial cell culture from adult human and murine tissues for the investigation of innate immune function

    PubMed Central

    Graves, Christina L.; Harden, Scott W.; LaPato, Melissa; Nelson, Michael; Amador, Byron; Sorenson, Heather; Frazier, Charles J.; Wallet, Shannon M.

    2015-01-01

    Intestinal epithelial cells (IECs) serve as an important physiologic barrier between environmental antigens and the host intestinal immune system. Thus, IECs serve as a first line of defense and may act as sentinel cells during inflammatory insults. Despite recent renewed interest in IEC contributions to host immune function, the study of primary IEC has been hindered by lack of a robust culture technique, particularly for small intestinal and adult tissues. Here, a novel adaptation for culture of primary IEC is described for human duodenal organ donor tissue as well as duodenum and colon of adult mice. These epithelial cell cultures display characteristic phenotypes and are of high purity. In addition, the innate immune function of human primary IEC, specifically with regard to Toll-like receptor (TLR) expression and microbial ligand responsiveness, is contrasted with a commonly used intestinal epithelial cell line (HT-29). Specifically, TLR expression at the mRNA level and production of cytokine (IFNγ and TNFα) in response to TLR agonist stimulation is assessed. Differential expression of TLRs as well as innate immune responses to ligand stimulation is observed in human-derived cultures compared to that of HT-29. Thus, use of this adapted method to culture primary epithelial cells from adult human donors and from adult mice will allow for more appropriate studies of IECs as innate immune effectors. PMID:25193428

  14. A method for high purity intestinal epithelial cell culture from adult human and murine tissues for the investigation of innate immune function.

    PubMed

    Graves, Christina L; Harden, Scott W; LaPato, Melissa; Nelson, Michael; Amador, Byron; Sorenson, Heather; Frazier, Charles J; Wallet, Shannon M

    2014-12-01

    Intestinal epithelial cells (IECs) serve as an important physiologic barrier between environmental antigens and the host intestinal immune system. Thus, IECs serve as a first line of defense and may act as sentinel cells during inflammatory insults. Despite recent renewed interest in IEC contributions to host immune function, the study of primary IEC has been hindered by lack of a robust culture technique, particularly for small intestinal and adult tissues. Here, a novel adaptation for culture of primary IEC is described for human duodenal organ donor tissue as well as duodenum and colon of adult mice. These epithelial cell cultures display characteristic phenotypes and are of high purity. In addition, the innate immune function of human primary IEC, specifically with regard to Toll-like receptor (TLR) expression and microbial ligand responsiveness, is contrasted with a commonly used intestinal epithelial cell line (HT-29). Specifically, TLR expression at the mRNA level and production of cytokine (IFNγ and TNFα) in response to TLR agonist stimulation is assessed. Differential expression of TLRs as well as innate immune responses to ligand stimulation is observed in human-derived cultures compared to that of HT-29. Thus, use of this adapted method to culture primary epithelial cells from adult human donors and from adult mice will allow for more appropriate studies of IECs as innate immune effectors.

  15. Fibrinogen adsorption and host tissue responses to plasma functionalized surfaces.

    PubMed

    Tang, L; Wu, Y; Timmons, R B

    1998-10-01

    The physical and chemical characteristics of material surfaces are thought to play important roles in biomaterial-mediated tissue responses. To understand the importance of discrete biomaterial chemical characteristics in modifying host tissue responses, we constructed surfaces bearing different functional groups using radio frequency glow discharge plasma polymerization. Surfaces evaluated included those having high concentrations of -OH, -NH2, -CF3, and siloxyl groups. These surfaces and polyethylene terephthalate controls were used to assess the importance of particular physicochemical characteristics in surface:protein:cell interactions both in vitro and in vivo. The results obtained show that surface functionalities do significantly affect both the adsorption and "denaturation" of adsorbed fibrinogen (which is an important mediator of inflammatory responses to biomaterial implants). In addition, these surfaces provoke different degrees of acute inflammatory responses. Interestingly, the amounts of "denatured" fibrinogen that spontaneously accumulate on the individual surfaces correlate closely with the extent of biomaterial-mediated inflammation. These results suggest that surfaces that tend to "irreversibly" bind fibrinogen prompt greater acute inflammatory responses. Unexpectedly, all test surfaces except those bearing a siloxyl group engender relatively similar biomaterial-mediated fibrotic responses. Thus surface functionalities alone may not be sufficient to affect subsequent fibrotic responses.

  16. Connective Tissue Growth Factor Promotes Pulmonary Epithelial Cell Senescence and Is Associated with COPD Severity.

    PubMed

    Jang, Jun-Ho; Chand, Hitendra S; Bruse, Shannon; Doyle-Eisele, Melanie; Royer, Christopher; McDonald, Jacob; Qualls, Clifford; Klingelhutz, Aloysius J; Lin, Yong; Mallampalli, Rama; Tesfaigzi, Yohannes; Nyunoya, Toru

    2017-04-01

    The purpose of this study was to determine whether expression of connective tissue growth factor (CTGF) protein in chronic obstructive pulmonary disease (COPD) is consistent in humans and animal models of COPD and to investigate the role of this protein in lung epithelial cells. CTGF in lung epithelial cells of ex-smokers with COPD was compared with ex-smokers without COPD by immunofluorescence. A total of twenty C57Bl/6 mice and sixteen non-human primates (NHPs) were exposed to cigarette smoke (CS) for 4 weeks. Ten mice of these CS-exposed mice and eight of the CS-exposed NHPs were infected with H3N2 influenza A virus (IAV), while the remaining ten mice and eight NHPs were mock-infected with vehicle as control. Both mRNA and protein expression of CTGF in lung epithelial cells of mice and NHPs were determined. The effects of CTGF overexpression on cell proliferation, p16 protein, and senescence-associated β-galactosidase (SA-β-gal) activity were examined in cultured human bronchial epithelial cells (HBECs). In humans, CTGF expression increased with increasing COPD severity. We found that protein expression of CTGF was upregulated in lung epithelial cells in both mice and NHPs exposed to CS and infected with IAV compared to those exposed to CS only. When overexpressed in HBECs, CTGF accelerated cellular senescence accompanied by p16 accumulation. Both CTGF and p16 protein expression in lung epithelia are positively associated with the severity of COPD in ex-smokers. These findings show that CTGF is consistently expressed in epithelial cells of COPD lungs. By accelerating lung epithelial senescence, CTGF may block regeneration relative to epithelial cell loss and lead to emphysema.

  17. Epithelial machines of morphogenesis and their potential application in organ assembly and tissue engineering

    PubMed Central

    Joshi, Sagar D.; Davidson, Lance A.

    2013-01-01

    Sheets of embryonic epithelial cells coordinate their efforts to create diverse tissue structures such as pits, grooves, tubes, and capsules that lead to organ formation. Such cells can use a number of cell behaviors including contractility, proliferation, and directed movement to create these structures. By contrast, tissue engineers and researchers in regenerative medicine seeking to produce organs for repair or replacement therapy can combine cells with synthetic polymeric scaffolds. Tissue engineers try to achieve these goals by shaping scaffold geometry in such a way that cells embedded within these scaffold self-assemble to form a tissue, for instance aligning to synthetic fibers, and assembling native extracellular matrix to form the desired tissue-like structure. Although self-assembly is a dominant process that guides tissue assembly both within the embryo and within artificial tissue constructs we know little about these critical processes. Here, we compare and contrast strategies of tissue assembly used by embryos to those used by engineers during epithelial morphogenesis and highlight opportunities for future applications of developmental biology in the field of tissue engineering. PMID:22854913

  18. ELF5 in epithelial ovarian carcinoma tissues and biological behavior in ovarian carcinoma cells.

    PubMed

    Yan, Hongchao; Qiu, Linglin; Xie, Xiaolei; Yang, He; Liu, Yongli; Lin, Xiaoman; Huang, Hongxiang

    2017-03-01

    The expression of E74-like factor 5 (ELF5) in epithelial ovarian carcinoma tissues and its effects on biological behavior in ovarian carcinoma cells were assessed in search for a new approach for gene treatment of epithelial ovarian carcinoma. RT-PCR technology was applied to detect the expression of ELF5 mRNA in epithelial ovarian carcinoma (n=49), borderline ovarian epithelial tumor (n=19), benign ovarian epithelial tumor (n=31) and normal ovarian tissues (n=40). Then, we transfected recombinant plasmid pcDNA3.1‑ELF5+EGFP into human ovarian carcinoma SKOV3 cells (recombinant plasmid group) in vitro and screened out stably transfected cells to conduct multiplication culture. Western blot analysis was performed to detect the expression of ELF5 protein in the different groups. Flow cytometry was employed to detect cell apoptosis and cycles. ELF5 mRNA in epithelial ovarian carcinoma and borderline ovarian epithelial tumor tissues were significantly lower (P<0.05) than those in benign ovarian epithelial tumor and normal ovarian tissues. ELF5 protein expression in the cells of recombinant plasmid group was significantly higher compared with empty plasmid and blank control groups. The capacity of cell reproductive recombinant plasmid group at each time point decreased (P<0.05). Flow cytometry detection showed that 67.03% of cells in recombinant plasmid group was blocked in G0/G1 phase (P<0.05), compared with empty plasmid group (37.17%) and blank control group (38.24%). Apoptotic rate of recombinant plasmid group was significantly lower (31.4±1.9%; P<0.05), compared with that of empty plasmid group (9.1±2.2%) and blank control group (8.7±1.5%), and the differences were statistically significant. In conclusion, ELF5 interfered with cell cycle of human ovarian carcinoma SKOV3 cells and promoted apoptosis of human ovarian carcinoma SKOV3 cells inhibiting their growth and invasive capacity; and thus providing a new approach to gene treatment of ovarian carcinoma.

  19. ELF5 in epithelial ovarian carcinoma tissues and biological behavior in ovarian carcinoma cells

    PubMed Central

    Yan, Hongchao; Qiu, Linglin; Xie, Xiaolei; Yang, He; Liu, Yongli; Lin, Xiaoman; Huang, Hongxiang

    2017-01-01

    The expression of E74-like factor 5 (ELF5) in epithelial ovarian carcinoma tissues and its effects on biological behavior in ovarian carcinoma cells were assessed in search for a new approach for gene treatment of epithelial ovarian carcinoma. RT-PCR technology was applied to detect the expression of ELF5 mRNA in epithelial ovarian carcinoma (n=49), borderline ovarian epithelial tumor (n=19), benign ovarian epithelial tumor (n=31) and normal ovarian tissues (n=40). Then, we transfected recombinant plasmid pcDNA3.1-ELF5+EGFP into human ovarian carcinoma SKOV3 cells (recombinant plasmid group) in vitro and screened out stably transfected cells to conduct multiplication culture. Western blot analysis was performed to detect the expression of ELF5 protein in the different groups. Flow cytometry was employed to detect cell apoptosis and cycles. ELF5 mRNA in epithelial ovarian carcinoma and borderline ovarian epithelial tumor tissues were significantly lower (P<0.05) than those in benign ovarian epithelial tumor and normal ovarian tissues. ELF5 protein expression in the cells of recombinant plasmid group was significantly higher compared with empty plasmid and blank control groups. The capacity of cell reproductive recombinant plasmid group at each time point decreased (P<0.05). Flow cytometry detection showed that 67.03% of cells in recombinant plasmid group was blocked in G0/G1 phase (P<0.05), compared with empty plasmid group (37.17%) and blank control group (38.24%). Apoptotic rate of recombinant plasmid group was significantly lower (31.4±1.9%; P<0.05), compared with that of empty plasmid group (9.1±2.2%) and blank control group (8.7±1.5%), and the differences were statistically significant. In conclusion, ELF5 interfered with cell cycle of human ovarian carcinoma SKOV3 cells and promoted apoptosis of human ovarian carcinoma SKOV3 cells inhibiting their growth and invasive capacity; and thus providing a new approach to gene treatment of ovarian carcinoma. PMID

  20. Segmentation and Tracking of Adherens Junctions in 3D for the Analysis of Epithelial Tissue Morphogenesis

    PubMed Central

    Cilla, Rodrigo; Mechery, Vinodh; Hernandez de Madrid, Beatriz; Del Signore, Steven; Dotu, Ivan; Hatini, Victor

    2015-01-01

    Epithelial morphogenesis generates the shape of tissues, organs and embryos and is fundamental for their proper function. It is a dynamic process that occurs at multiple spatial scales from macromolecular dynamics, to cell deformations, mitosis and apoptosis, to coordinated cell rearrangements that lead to global changes of tissue shape. Using time lapse imaging, it is possible to observe these events at a system level. However, to investigate morphogenetic events it is necessary to develop computational tools to extract quantitative information from the time lapse data. Toward this goal, we developed an image-based computational pipeline to preprocess, segment and track epithelial cells in 4D confocal microscopy data. The computational pipeline we developed, for the first time, detects the adherens junctions of epithelial cells in 3D, without the need to first detect cell nuclei. We accentuate and detect cell outlines in a series of steps, symbolically describe the cells and their connectivity, and employ this information to track the cells. We validated the performance of the pipeline for its ability to detect vertices and cell-cell contacts, track cells, and identify mitosis and apoptosis in surface epithelia of Drosophila imaginal discs. We demonstrate the utility of the pipeline to extract key quantitative features of cell behavior with which to elucidate the dynamics and biomechanical control of epithelial tissue morphogenesis. We have made our methods and data available as an open-source multiplatform software tool called TTT (http://github.com/morganrcu/TTT) PMID:25884654

  1. Segmentation and tracking of adherens junctions in 3D for the analysis of epithelial tissue morphogenesis.

    PubMed

    Cilla, Rodrigo; Mechery, Vinodh; Hernandez de Madrid, Beatriz; Del Signore, Steven; Dotu, Ivan; Hatini, Victor

    2015-04-01

    Epithelial morphogenesis generates the shape of tissues, organs and embryos and is fundamental for their proper function. It is a dynamic process that occurs at multiple spatial scales from macromolecular dynamics, to cell deformations, mitosis and apoptosis, to coordinated cell rearrangements that lead to global changes of tissue shape. Using time lapse imaging, it is possible to observe these events at a system level. However, to investigate morphogenetic events it is necessary to develop computational tools to extract quantitative information from the time lapse data. Toward this goal, we developed an image-based computational pipeline to preprocess, segment and track epithelial cells in 4D confocal microscopy data. The computational pipeline we developed, for the first time, detects the adherens junctions of epithelial cells in 3D, without the need to first detect cell nuclei. We accentuate and detect cell outlines in a series of steps, symbolically describe the cells and their connectivity, and employ this information to track the cells. We validated the performance of the pipeline for its ability to detect vertices and cell-cell contacts, track cells, and identify mitosis and apoptosis in surface epithelia of Drosophila imaginal discs. We demonstrate the utility of the pipeline to extract key quantitative features of cell behavior with which to elucidate the dynamics and biomechanical control of epithelial tissue morphogenesis. We have made our methods and data available as an open-source multiplatform software tool called TTT (http://github.com/morganrcu/TTT).

  2. Lactobacilli Reduce Helicobacter pylori Attachment to Host Gastric Epithelial Cells by Inhibiting Adhesion Gene Expression

    PubMed Central

    de Klerk, Nele; Maudsdotter, Lisa; Gebreegziabher, Hanna; Saroj, Sunil D.; Eriksson, Beatrice; Eriksson, Olaspers Sara; Roos, Stefan; Lindén, Sara; Sjölinder, Hong

    2016-01-01

    The human gastrointestinal tract, including the harsh environment of the stomach, harbors a large variety of bacteria, of which Lactobacillus species are prominent members. The molecular mechanisms by which species of lactobacilli interfere with pathogen colonization are not fully characterized. In this study, we aimed to study the effect of lactobacillus strains upon the initial attachment of Helicobacter pylori to host cells. Here we report a novel mechanism by which lactobacilli inhibit adherence of the gastric pathogen H. pylori. In a screen with Lactobacillus isolates, we found that only a few could reduce adherence of H. pylori to gastric epithelial cells. Decreased attachment was not due to competition for space or to lactobacillus-mediated killing of the pathogen. Instead, we show that lactobacilli act on H. pylori directly by an effector molecule that is released into the medium. This effector molecule acts on H. pylori by inhibiting expression of the adhesin-encoding gene sabA. Finally, we verified that inhibitory lactobacilli reduced H. pylori colonization in an in vivo model. In conclusion, certain Lactobacillus strains affect pathogen adherence by inhibiting sabA expression and thereby reducing H. pylori binding capacity. PMID:26930708

  3. Lactobacilli Reduce Helicobacter pylori Attachment to Host Gastric Epithelial Cells by Inhibiting Adhesion Gene Expression.

    PubMed

    de Klerk, Nele; Maudsdotter, Lisa; Gebreegziabher, Hanna; Saroj, Sunil D; Eriksson, Beatrice; Eriksson, Olaspers Sara; Roos, Stefan; Lindén, Sara; Sjölinder, Hong; Jonsson, Ann-Beth

    2016-05-01

    The human gastrointestinal tract, including the harsh environment of the stomach, harbors a large variety of bacteria, of which Lactobacillus species are prominent members. The molecular mechanisms by which species of lactobacilli interfere with pathogen colonization are not fully characterized. In this study, we aimed to study the effect of lactobacillus strains upon the initial attachment of Helicobacter pylori to host cells. Here we report a novel mechanism by which lactobacilli inhibit adherence of the gastric pathogen H. pylori In a screen with Lactobacillus isolates, we found that only a few could reduce adherence of H. pylori to gastric epithelial cells. Decreased attachment was not due to competition for space or to lactobacillus-mediated killing of the pathogen. Instead, we show that lactobacilli act on H. pylori directly by an effector molecule that is released into the medium. This effector molecule acts on H. pylori by inhibiting expression of the adhesin-encoding gene sabA Finally, we verified that inhibitory lactobacilli reduced H. pylori colonization in an in vivo model. In conclusion, certain Lactobacillus strains affect pathogen adherence by inhibiting sabA expression and thereby reducing H. pylori binding capacity.

  4. Remodeling of the Epithelial-Connective Tissue Interface in Oral Epithelial Dysplasia as Visualized by Noninvasive 3D Imaging.

    PubMed

    Pal, Rahul; Shilagard, Tuya; Yang, Jinping; Villarreal, Paula; Brown, Tyra; Qiu, Suimin; McCammon, Susan; Resto, Vicente; Vargas, Gracie

    2016-08-15

    Early neoplastic features in oral epithelial dysplasia are first evident at the basal epithelium positioned at the epithelial-connective tissue interface (ECTI), separating the basal epithelium from the underlying lamina propria. The ECTI undergoes significant deformation in early neoplasia due to focal epithelial expansion and proteolytic remodeling of the lamina propria, but few studies have examined these changes. In the present study, we quantitated alterations in ECTI topography in dysplasia using in vivo volumetric multiphoton autofluorescence microscopy and second harmonic generation microscopy. The label-free method allows direct noninvasive visualization of the ECTI surface without perturbing the epithelium. An image-based parameter, "ECTI contour," is described that indicates deformation of the ECTI surface. ECTI contour was higher in dysplasia than control or inflamed specimens, indicating transition from flat to a deformed surface. Cellular parameters of nuclear area, nuclear density, coefficient of variation in nuclear area in the basal epithelium and collagen density in areas adjacent to ECTI were measured. ECTI contour differentiated dysplasia from control/benign mucosa with higher sensitivity and specificity than basal nuclear density or basal nuclear area, comparable with coefficient of variation in nuclear area and collagen density. The presented method offers a unique opportunity to study ECTI in intact mucosa with simultaneous assessment of cellular and extracellular matrix features, expanding opportunities for studies of early neoplastic events near this critical interface and potentially leading to development of new approaches for detecting neoplasia in vivo Cancer Res; 76(16); 4637-47. ©2016 AACR. ©2016 American Association for Cancer Research.

  5. Photochemical bonding of epithelial cell-seeded collagen lattice to rat muscle layer for esophageal tissue engineering: a pilot study

    NASA Astrophysics Data System (ADS)

    Chan, Barbara P.; Sato, M.; Vacanti, Joseph P.; Kochevar, Irene E.; Redmond, Robert W.

    2005-04-01

    Bilayered tube structures consist of epithelial cell-seeded collagen lattice and muscle layer have been fabricated for esophageal tissue engineering. Good adhesion between layers in order to facilitate cell infiltration and neovascularization in the collagen lattice is required. Previous efforts include using other bioglues such as fibrin glue and silicone tube as the physical support. However, the former is subjected to chances of transmitting blood-born infectious disease and is time consuming while the latter requires a second surgical procedure. The current project aimed to bond the cell-seeded collagen lattice to muscle layer using photochemical bonding, which has previously been demonstrated a rapid and non-thermal procedure in bonding collagenous tissues. Rat esophageal epithelial cells were seeded on collagen lattice and together with the latissimus dorsi muscle layer, were exposed to a photosensitizer rose Bengal at the bonding surface. An argon laser was used to irradiate the approximated layers. Bonding strength was measured during the peeling test of the collagen layer from the muscle layer. Post-bonding cell viability was assessed using a modified NADH-diaphorase microassay. A pilot in vivo study was conducted by directly bonding the cell-seeded collagen layer onto the muscle flap in rats and the structures were characterized histologically. Photochemical bonding was found to significantly increase the adherence at the bonding interface without compromising the cell viability. This indicates the feasibility of using the technique to fabricate multi-layered structures in the presence of living cells. The pilot animal study demonstrated integration of the collagen lattice with the muscle layer at the bonding interface although the subsequent surgical manipulation disturbed the integration at some region. This means that an additional procedure removing the tube could be avoided if the approximation and thus the bonding are optimized. Cell infiltration

  6. The role of sialyl glycan recognition in host tissue tropism of the avian parasite Eimeria tenella.

    PubMed

    Lai, Livia; Bumstead, Janene; Liu, Yan; Garnett, James; Campanero-Rhodes, Maria A; Blake, Damer P; Palma, Angelina S; Chai, Wengang; Ferguson, David J P; Simpson, Peter; Feizi, Ten; Tomley, Fiona M; Matthews, Stephen

    2011-10-01

    Eimeria spp. are a highly successful group of intracellular protozoan parasites that develop within intestinal epithelial cells of poultry, causing coccidiosis. As a result of resistance against anticoccidial drugs and the expense of manufacturing live vaccines, it is necessary to understand the relationship between Eimeria and its host more deeply, with a view to developing recombinant vaccines. Eimeria possesses a family of microneme lectins (MICs) that contain microneme adhesive repeat regions (MARR). We show that the major MARR protein from Eimeria tenella, EtMIC3, is deployed at the parasite-host interface during the early stages of invasion. EtMIC3 consists of seven tandem MAR1-type domains, which possess a high specificity for sialylated glycans as shown by cell-based assays and carbohydrate microarray analyses. The restricted tissue staining pattern observed for EtMIC3 in the chicken caecal epithelium indicates that EtMIC3 contributes to guiding the parasite to the site of invasion in the chicken gut. The microarray analyses also reveal a lack of recognition of glycan sequences terminating in the N-glycolyl form of sialic acid by EtMIC3. Thus the parasite is well adapted to the avian host which lacks N-glycolyl neuraminic acid. We provide new structural insight into the MAR1 family of domains and reveal the atomic resolution basis for the sialic acid-based carbohydrate recognition. Finally, a preliminary chicken immunization trial provides evidence that recombinant EtMIC3 protein and EtMIC3 DNA are effective vaccine candidates.

  7. Epithelial bridges maintain tissue integrity during collective cell migration.

    PubMed

    Vedula, Sri Ram Krishna; Hirata, Hiroaki; Nai, Mui Hoon; Brugués, Agustí; Toyama, Yusuke; Trepat, Xavier; Lim, Chwee Teck; Ladoux, Benoit

    2014-01-01

    The ability of skin to act as a barrier is primarily determined by the efficiency of skin cells to maintain and restore its continuity and integrity. In fact, during wound healing keratinocytes migrate collectively to maintain their cohesion despite heterogeneities in the extracellular matrix. Here, we show that monolayers of human keratinocytes migrating along functionalized micropatterned surfaces comprising alternating strips of extracellular matrix (fibronectin) and non-adherent polymer form suspended multicellular bridges over the non-adherent areas. The bridges are held together by intercellular adhesion and are subjected to considerable tension, as indicated by the presence of prominent actin bundles. We also show that a model based on force propagation through an elastic material reproduces the main features of bridge maintenance and tension distribution. Our findings suggest that multicellular bridges maintain tissue integrity during wound healing when cell-substrate interactions are weak and may prove helpful in the design of artificial scaffolds for skin regeneration.

  8. Epithelial bridges maintain tissue integrity during collective cell migration

    NASA Astrophysics Data System (ADS)

    Vedula, Sri Ram Krishna; Hirata, Hiroaki; Nai, Mui Hoon; Brugués, Agustí; Toyama, Yusuke; Trepat, Xavier; Lim, Chwee Teck; Ladoux, Benoit

    2014-01-01

    The ability of skin to act as a barrier is primarily determined by the efficiency of skin cells to maintain and restore its continuity and integrity. In fact, during wound healing keratinocytes migrate collectively to maintain their cohesion despite heterogeneities in the extracellular matrix. Here, we show that monolayers of human keratinocytes migrating along functionalized micropatterned surfaces comprising alternating strips of extracellular matrix (fibronectin) and non-adherent polymer form suspended multicellular bridges over the non-adherent areas. The bridges are held together by intercellular adhesion and are subjected to considerable tension, as indicated by the presence of prominent actin bundles. We also show that a model based on force propagation through an elastic material reproduces the main features of bridge maintenance and tension distribution. Our findings suggest that multicellular bridges maintain tissue integrity during wound healing when cell-substrate interactions are weak and may prove helpful in the design of artificial scaffolds for skin regeneration.

  9. FGF8 coordinates tissue elongation and cell epithelialization during early kidney tubulogenesis

    PubMed Central

    Atsuta, Yuji; Takahashi, Yoshiko

    2015-01-01

    When a tubular structure forms during early embryogenesis, tubular elongation and lumen formation (epithelialization) proceed simultaneously in a spatiotemporally coordinated manner. We here demonstrate, using the Wolffian duct (WD) of early chicken embryos, that this coordination is regulated by the expression of FGF8, which shifts posteriorly during body axis elongation. FGF8 acts as a chemoattractant on the leader cells of the elongating WD and prevents them from epithelialization, whereas static (‘rear’) cells that receive progressively less FGF8 undergo epithelialization to form a lumen. Thus, FGF8 acts as a binary switch that distinguishes tubular elongation from lumen formation. The posteriorly shifting FGF8 is also known to regulate somite segmentation, suggesting that multiple types of tissue morphogenesis are coordinately regulated by macroscopic changes in body growth. PMID:26130757

  10. Structural Cues from the Tissue Microenvironment Are Essential Determinants of the Human Mammary Epithelial Cell Phenotype

    PubMed Central

    Schmeichel, Karen L.; Weaver, Valerie M.

    2010-01-01

    Historically, the study of normal human breast function and breast disorders has been significantly impaired by limitations inherent to available model systems. Recent improvements in human breast epithelial cell lines and three-dimensional (3-D)3 culture systems have contributed to the development of in vitro model systems that recapitulate differentiated epithelial cell phenotypes with remarkable fidelity. Molecular characterization of these human breast cell models has demonstrated that normal breast epithelial cell behavior is determined in part by the precise interplay that exists between a cell and its surrounding microenvironment. Recent functional studies of integrins in a human model system provide evidence to support the idea that the structural stability afforded by integrin-mediated cell-extracellular matrix interactions is an important determinant of normal cellular behavior, and that alterations in tissue structure can give rise to tumorigenic progression. PMID:10819528

  11. Intestinal epithelial MyD88 is a sensor switching host metabolism towards obesity according to nutritional status.

    PubMed

    Everard, Amandine; Geurts, Lucie; Caesar, Robert; Van Hul, Matthias; Matamoros, Sébastien; Duparc, Thibaut; Denis, Raphael G P; Cochez, Perrine; Pierard, Florian; Castel, Julien; Bindels, Laure B; Plovier, Hubert; Robine, Sylvie; Muccioli, Giulio G; Renauld, Jean-Christophe; Dumoutier, Laure; Delzenne, Nathalie M; Luquet, Serge; Bäckhed, Fredrik; Cani, Patrice D

    2014-12-05

    Obesity is associated with a cluster of metabolic disorders, low-grade inflammation and altered gut microbiota. Whether host metabolism is controlled by intestinal innate immune system and the gut microbiota is unknown. Here we report that inducible intestinal epithelial cell-specific deletion of MyD88 partially protects against diet-induced obesity, diabetes and inflammation. This is associated with increased energy expenditure, an improved glucose homeostasis, reduced hepatic steatosis, fat mass and inflammation. Protection is transferred following gut microbiota transplantation to germ-free recipients. We also demonstrate that intestinal epithelial MyD88 deletion increases anti-inflammatory endocannabinoids, restores antimicrobial peptides production and increases intestinal regulatory T cells during diet-induced obesity. Targeting MyD88 after the onset of obesity reduces fat mass and inflammation. Our work thus identifies intestinal epithelial MyD88 as a sensor changing host metabolism according to the nutritional status and we show that targeting intestinal epithelial MyD88 constitutes a putative therapeutic target for obesity and related disorders.

  12. Intestinal epithelial MyD88 is a sensor switching host metabolism towards obesity according to nutritional status

    PubMed Central

    Everard, Amandine; Geurts, Lucie; Caesar, Robert; Van Hul, Matthias; Matamoros, Sébastien; Duparc, Thibaut; Denis, Raphael G. P.; Cochez, Perrine; Pierard, Florian; Castel, Julien; Bindels, Laure B.; Plovier, Hubert; Robine, Sylvie; Muccioli, Giulio G.; Renauld, Jean-Christophe; Dumoutier, Laure; Delzenne, Nathalie M.; Luquet, Serge; Bäckhed, Fredrik; Cani, Patrice D.

    2014-01-01

    Obesity is associated with a cluster of metabolic disorders, low-grade inflammation and altered gut microbiota. Whether host metabolism is controlled by intestinal innate immune system and the gut microbiota is unknown. Here we report that inducible intestinal epithelial cell-specific deletion of MyD88 partially protects against diet-induced obesity, diabetes and inflammation. This is associated with increased energy expenditure, an improved glucose homeostasis, reduced hepatic steatosis, fat mass and inflammation. Protection is transferred following gut microbiota transplantation to germ-free recipients. We also demonstrate that intestinal epithelial MyD88 deletion increases anti-inflammatory endocannabinoids, restores antimicrobial peptides production and increases intestinal regulatory T cells during diet-induced obesity. Targeting MyD88 after the onset of obesity reduces fat mass and inflammation. Our work thus identifies intestinal epithelial MyD88 as a sensor changing host metabolism according to the nutritional status and we show that targeting intestinal epithelial MyD88 constitutes a putative therapeutic target for obesity and related disorders. PMID:25476696

  13. Experimental control of excitable embryonic tissues: three stimuli induce rapid epithelial contraction

    PubMed Central

    Joshi, Sagar D.; von Dassow, Michelangelo; Davidson, Lance. A.

    2009-01-01

    Cell generated contractility is a major driver of morphogenesis during processes such as epithelial bending and epithelial-to-mesenchymal transitions. Previous studies of contraction in embryos have relied on developmentally programmed cell shape changes such as those that accompany ventral furrow formation in Drosophila, bottle cell formation in Xenopus, ingression in amniote embryos, and neurulation in vertebrate embryos. We have identified three methods to reproducibly and acutely induce contraction in embryonic epithelial sheets: laser activation, electrical stimulation, and nano-perfusion with chemicals released by wounding. Contractions induced by all three methods occur over a similar time scale (1 to 2 min) and lead to reorganization of the F-actin cytoskeleton. By combining induced contractions with micro-aspiration we can simultaneously measure the stiffness of the tissue and the force and work done by contractions. Laser-activation allows real-time visualization of F-actin remodeling during contraction. Perfusion with cell-lysate suggests these three stimuli activate physiologically relevant pathways that maintain epithelial tension or trigger epithelial morphogenesis. Our methods provide the means to control and study cellular contractility and will allow dissection of molecular mechanisms and biomechanics of cellular contractility. PMID:19686733

  14. A Pulse Coupled Neural Network Segmentation Algorithm for Reflectance Confocal Images of Epithelial Tissue

    PubMed Central

    Malik, Bilal H.; Jabbour, Joey M.; Maitland, Kristen C.

    2015-01-01

    Automatic segmentation of nuclei in reflectance confocal microscopy images is critical for visualization and rapid quantification of nuclear-to-cytoplasmic ratio, a useful indicator of epithelial precancer. Reflectance confocal microscopy can provide three-dimensional imaging of epithelial tissue in vivo with sub-cellular resolution. Changes in nuclear density or nuclear-to-cytoplasmic ratio as a function of depth obtained from confocal images can be used to determine the presence or stage of epithelial cancers. However, low nuclear to background contrast, low resolution at greater imaging depths, and significant variation in reflectance signal of nuclei complicate segmentation required for quantification of nuclear-to-cytoplasmic ratio. Here, we present an automated segmentation method to segment nuclei in reflectance confocal images using a pulse coupled neural network algorithm, specifically a spiking cortical model, and an artificial neural network classifier. The segmentation algorithm was applied to an image model of nuclei with varying nuclear to background contrast. Greater than 90% of simulated nuclei were detected for contrast of 2.0 or greater. Confocal images of porcine and human oral mucosa were used to evaluate application to epithelial tissue. Segmentation accuracy was assessed using manual segmentation of nuclei as the gold standard. PMID:25816131

  15. Calcium spikes, waves and oscillations in a large, patterned epithelial tissue.

    PubMed

    Balaji, Ramya; Bielmeier, Christina; Harz, Hartmann; Bates, Jack; Stadler, Cornelia; Hildebrand, Alexander; Classen, Anne-Kathrin

    2017-02-20

    While calcium signaling in excitable cells, such as muscle or neurons, is extensively characterized, calcium signaling in epithelial tissues is little understood. Specifically, the range of intercellular calcium signaling patterns elicited by tightly coupled epithelial cells and their function in the regulation of epithelial characteristics are little explored. We found that in Drosophila imaginal discs, a widely studied epithelial model organ, complex spatiotemporal calcium dynamics occur. We describe patterns that include intercellular waves traversing large tissue domains in striking oscillatory patterns as well as spikes confined to local domains of neighboring cells. The spatiotemporal characteristics of intercellular waves and oscillations arise as emergent properties of calcium mobilization within a sheet of gap-junction coupled cells and are influenced by cell size and environmental history. While the in vivo function of spikes, waves and oscillations requires further characterization, our genetic experiments suggest that core calcium signaling components guide actomyosin organization. Our study thus suggests a possible role for calcium signaling in epithelia but importantly, introduces a model epithelium enabling the dissection of cellular mechanisms supporting the initiation, transmission and regeneration of long-range intercellular calcium waves and the emergence of oscillations in a highly coupled multicellular sheet.

  16. A pulse coupled neural network segmentation algorithm for reflectance confocal images of epithelial tissue.

    PubMed

    Harris, Meagan A; Van, Andrew N; Malik, Bilal H; Jabbour, Joey M; Maitland, Kristen C

    2015-01-01

    Automatic segmentation of nuclei in reflectance confocal microscopy images is critical for visualization and rapid quantification of nuclear-to-cytoplasmic ratio, a useful indicator of epithelial precancer. Reflectance confocal microscopy can provide three-dimensional imaging of epithelial tissue in vivo with sub-cellular resolution. Changes in nuclear density or nuclear-to-cytoplasmic ratio as a function of depth obtained from confocal images can be used to determine the presence or stage of epithelial cancers. However, low nuclear to background contrast, low resolution at greater imaging depths, and significant variation in reflectance signal of nuclei complicate segmentation required for quantification of nuclear-to-cytoplasmic ratio. Here, we present an automated segmentation method to segment nuclei in reflectance confocal images using a pulse coupled neural network algorithm, specifically a spiking cortical model, and an artificial neural network classifier. The segmentation algorithm was applied to an image model of nuclei with varying nuclear to background contrast. Greater than 90% of simulated nuclei were detected for contrast of 2.0 or greater. Confocal images of porcine and human oral mucosa were used to evaluate application to epithelial tissue. Segmentation accuracy was assessed using manual segmentation of nuclei as the gold standard.

  17. Calcium spikes, waves and oscillations in a large, patterned epithelial tissue

    PubMed Central

    Balaji, Ramya; Bielmeier, Christina; Harz, Hartmann; Bates, Jack; Stadler, Cornelia; Hildebrand, Alexander; Classen, Anne-Kathrin

    2017-01-01

    While calcium signaling in excitable cells, such as muscle or neurons, is extensively characterized, calcium signaling in epithelial tissues is little understood. Specifically, the range of intercellular calcium signaling patterns elicited by tightly coupled epithelial cells and their function in the regulation of epithelial characteristics are little explored. We found that in Drosophila imaginal discs, a widely studied epithelial model organ, complex spatiotemporal calcium dynamics occur. We describe patterns that include intercellular waves traversing large tissue domains in striking oscillatory patterns as well as spikes confined to local domains of neighboring cells. The spatiotemporal characteristics of intercellular waves and oscillations arise as emergent properties of calcium mobilization within a sheet of gap-junction coupled cells and are influenced by cell size and environmental history. While the in vivo function of spikes, waves and oscillations requires further characterization, our genetic experiments suggest that core calcium signaling components guide actomyosin organization. Our study thus suggests a possible role for calcium signaling in epithelia but importantly, introduces a model epithelium enabling the dissection of cellular mechanisms supporting the initiation, transmission and regeneration of long-range intercellular calcium waves and the emergence of oscillations in a highly coupled multicellular sheet. PMID:28218282

  18. Initial symbiont contact orchestrates host-organ-wide transcriptional changes that prime tissue colonization.

    PubMed

    Kremer, Natacha; Philipp, Eva E R; Carpentier, Marie-Christine; Brennan, Caitlin A; Kraemer, Lars; Altura, Melissa A; Augustin, René; Häsler, Robert; Heath-Heckman, Elizabeth A C; Peyer, Suzanne M; Schwartzman, Julia; Rader, Bethany A; Ruby, Edward G; Rosenstiel, Philip; McFall-Ngai, Margaret J

    2013-08-14

    Upon transit to colonization sites, bacteria often experience critical priming that prepares them for subsequent, specific interactions with the host; however, the underlying mechanisms are poorly described. During initiation of the symbiosis between the bacterium Vibrio fischeri and its squid host, which can be observed directly and in real time, approximately five V. fischeri cells aggregate along the mucociliary membranes of a superficial epithelium prior to entering host tissues. Here, we show that these few early host-associated symbionts specifically induce robust changes in host gene expression that are critical to subsequent colonization steps. This exquisitely sensitive response to the host's specific symbiotic partner includes the upregulation of a host endochitinase, whose activity hydrolyzes polymeric chitin in the mucus into chitobiose, thereby priming the symbiont and also producing a chemoattractant gradient that promotes V. fischeri migration into host tissues. Thus, the host responds transcriptionally upon initial symbiont contact, which facilitates subsequent colonization.

  19. Temporal Transcriptional Response during Infection of Type II Alveolar Epithelial Cells with Francisella tularensis Live Vaccine Strain (LVS) Supports a General Host Suppression and Bacterial Uptake by Macropinocytosis*

    PubMed Central

    Bradburne, Christopher E.; Verhoeven, Anne B.; Manyam, Ganiraju C.; Chaudhry, Saira A.; Chang, Eddie L.; Thach, Dzung C.; Bailey, Charles L.; van Hoek, Monique L.

    2013-01-01

    Pneumonic tularemia is caused by inhalation of Francisella tularensis, one of the most infectious microbes known. We wanted to study the kinetics of the initial and early interactions between bacterium and host cells in the lung. To do this, we examined the infection of A549 airway epithelial cells with the live vaccine strain (LVS) of F. tularensis. A549 cells were infected and analyzed for global transcriptional response at multiple time points up to 16 h following infection. At 15 min and 2 h, a strong transcriptional response was observed including cytoskeletal rearrangement, intracellular transport, and interferon signaling. However, at later time points (6 and 16 h), very little differential gene expression was observed, indicating a general suppression of the host response consistent with other reported cell lines and murine tissues. Genes for macropinocytosis and actin/cytoskeleton rearrangement were highly up-regulated and common to the 15 min and 2 h time points, suggesting the use of this method for bacterial entry into cells. We demonstrate macropinocytosis through the uptake of FITC-dextran and amiloride inhibition of Francisella LVS uptake. Our results suggest that macropinocytosis is a potential mechanism of intracellular entry by LVS and that the host cell response is suppressed during the first 2–6 h of infection. These results suggest that the attenuated Francisella LVS induces significant host cell signaling at very early time points after the bacteria's interaction with the cell. PMID:23322778

  20. Exploring processes of organization of normal and neoplastic epithelial tissues in gradient culture.

    PubMed

    Leighton, J

    1994-09-01

    The biology of animal cells in culture is often studied in individual cells or in sheets of cells. The relevance of such studies to the intact animal is unclear, since the spatial conditions encountered by cells in animals is one of dense three-dimensional masses of cells, with limits to migration, and with gradients both of diffusion of metabolites and of morphologic maturation. These spatial requisites have gradually been met in culture. A brief account describes sponge matrix culture for three-dimensional growth and unilaminar, bilaminar, and radial histophysiologic gradient cultures. Some of the common neoplastic abnormalities of surface epithelial tissues are considered. Proposals for investigating the histokinetic mechanisms regulating some epithelial tissue processes are suggested. In the most recent development of gradient culture methods, a thin permeable transparent collagen membrane is intrinsically strengthened by producing a waffle membrane pattern for histophysiologic gradient culture.

  1. The Epithelial-Mesenchymal Interactions: Insights into Physiological and Pathological Aspects of Oral Tissues

    PubMed Central

    Santosh, Arvind Babu Rajendra; Jones, Thaon Jon

    2014-01-01

    In the human biological system, the individual cells divide and form tissues and organs. These tissues are hetero-cellular. Basically any tissue consists of an epithelium and the connective tissue. The latter contains mainly mesenchymally-derived tissues with a diversified cell population. The cell continues to grow and differentiate in a pre-programmed manner using a messenger system. The epithelium and the mesenchymal portion of each tissue have two different origins and perform specific functions, but there is a well-defined interaction mechanism, which mediates between them. Epithelial mesenchymal interactions (EMIs) are part of this mechanism, which can be regarded as a biological conversation between epithelial and mesenchymal cell populations involved in the cellular differentiation of one or both cell populations. EMIs represent a process that is essential for cell growth, cell differentiation and cell multiplication. EMIs are associated with normal physiological processes in the oral cavity, such as odontogenesis, dentino-enamel junction formation, salivary gland development, palatogenesis, and also pathological processes, such as oral cancer. This paper focuses the role EMIs in odontogenesis, salivary gland development, palatogenesis and oral cancer. PMID:25992230

  2. The epithelial-mesenchymal interactions: insights into physiological and pathological aspects of oral tissues.

    PubMed

    Santosh, Arvind Babu Rajendra; Jones, Thaon Jon

    2014-03-17

    In the human biological system, the individual cells divide and form tissues and organs. These tissues are hetero-cellular. Basically any tissue consists of an epithelium and the connective tissue. The latter contains mainly mesenchymally-derived tissues with a diversified cell population. The cell continues to grow and differentiate in a pre-programmed manner using a messenger system. The epithelium and the mesenchymal portion of each tissue have two different origins and perform specific functions, but there is a well-defined interaction mechanism, which mediates between them. Epithelial mesenchymal interactions (EMIs) are part of this mechanism, which can be regarded as a biological conversation between epithelial and mesenchymal cell populations involved in the cellular differentiation of one or both cell populations. EMIs represent a process that is essential for cell growth, cell differentiation and cell multiplication. EMIs are associated with normal physiological processes in the oral cavity, such as odontogenesis, dentino-enamel junction formation, salivary gland development, palatogenesis, and also pathological processes, such as oral cancer. This paper focuses the role EMIs in odontogenesis, salivary gland development, palatogenesis and oral cancer.

  3. Rescue of embryonic epithelium reveals that the homozygous deletion of the retinoblastoma gene confers growth factor independence and immortality but does not influence epithelial differentiation or tissue morphogenesis.

    PubMed

    Day, Kathleen C; McCabe, Michael T; Zhao, Xin; Wang, Yuzhuo; Davis, Joanne N; Phillips, John; Von Geldern, Marion; Ried, Thomas; KuKuruga, Mark A; Cunha, Gerald R; Hayward, Simon W; Day, Mark L

    2002-11-15

    The ability to rescue viable prostate precursor tissue from retinoblastoma-deficient (Rb-/-) fetal mice has allowed for the isolation and characterization of the first Rb-/- prostate epithelial cell line. This cell line, designated Rb-/-PrE, was utilized for experiments examining the consequences of Rb loss on an epithelial population. These findings demonstrated that Rb deletion has no discernible effect on prostatic histodifferentiation in Rb-/-PrE cultures. When Rb-/-PrE cells were recombined with embryonic rat urogenital mesenchyme and implanted into athymic male, nude mouse hosts, the recombinants developed into fully differentiated and morphologically normal prostate tissue. The Rb-/-PrE phenotype was characterized by serum independence in culture and immortality in vivo, when compared with wild type controls. Cell cycle analysis revealed elevated S phase DNA content accompanied by increased expression of cyclin E1 and proliferating cell nuclear antigen. Rb-/-PrE cultures also exhibited a diminished ability to growth arrest under high density culture conditions. We believe that the development of Rb-/- prostate tissue and cell lines has provided a unique experimental platform with which to investigate the consequences of Rb deletion in epithelial cells under various physiological conditions. Additionally, the development of this technology will allow similar studies in other tissues and cell populations rescued from Rb-/- fetuses.

  4. Tumor suppressor roles of CENP-E and Nsl1 in Drosophila epithelial tissues.

    PubMed

    Clemente-Ruiz, Marta; Muzzopappa, Mariana; Milán, Marco

    2014-01-01

    Depletion of spindle assembly checkpoint (SAC) genes in Drosophila epithelial tissues leads to JNK-dependent programmed cell death and additional blockade of the apoptotic program drives tumorigenesis. A recent report proposes that chromosomal instability (CIN) is not the driving force in the tumorigenic response of the SAC-deficient tissue, and that checkpoint proteins exert a SAC-independent tumor suppressor role. This notion is based on observations that the depletion of CENP-E levels or prevention of Bub3 from binding to the kinetochore in Drosophila tissues unable to activate the apoptotic program induces CIN but does not cause hyperproliferation. Here we re-examined this proposal. In contrast to the previous report, we observed that depletion of CENP-E or Nsl1-the latter mediating kinetochore targeting of Bub3-in epithelial tissues unable to activate the apoptotic program induces significant levels of aneuploidy and drives tumor-like growth. The induction of the JNK transcriptional targets Wingless, a mitogenic molecule, and MMP1, a matrix metaloproteinase 1 involved in basement membrane degradation was also observed in these tumors. An identical response of the tissue was previously detected upon depletion of several SAC genes or genes involved in spindle assembly, chromatin condensation, and cytokinesis, all of which have been described to cause CIN. All together, these results reinforce the role of CIN in driving tumorigenesis in Drosophila epithelial tissues and question the proposed SAC-independent roles of checkpoint proteins in suppressing tumorigenesis. Differences in aneuploidy rates might explain the discrepancy between the previous report and our results.

  5. Human Bone Marrow Stromal Cells Differentiate Into Corneal Tissue and Prevent Ocular Graft-Versus-Host Disease in Mice.

    PubMed

    Sánchez-Abarca, Luis Ignacio; Hernández-Galilea, Emiliano; Lorenzo, Rebeca; Herrero, Carmen; Velasco, Almudena; Carrancio, Soraya; Caballero-Velázquez, Teresa; Rodríguez-Barbosa, José Ignacio; Parrilla, Marta; Del Cañizo, Consuelo; San Miguel, Jesús; Aijón, José; Pérez-Simón, José Antonio

    2015-01-01

    Clinical trials have assessed the use of human bone marrow stromal cells (hBMSCs) for the treatment of immune-related disorders such as graft-versus-host disease (GVHD). In the current study, we show that GFP(+)-transduced hBMSCs generated from bone marrow migrate and differentiate into corneal tissue after subconjunctival injection in mice. Interestingly, these hBMSCs display morphological features of epithelial, stromal, and endothelial cells and appear at different layers and with different morphologies depending on their position within the epithelium. Furthermore, these cells display ultrastructural properties, such as bundles of intermediate filaments, interdigitations, and desmosomes with GFP(-) cells, which confirms their differentiation into corneal tissues. GFP(+)-transduced hBMSCs were injected at different time points into the right eye of lethally irradiated mice undergoing bone marrow transplantation, which developed ocular GVHD (oGVHD). Remarkably, hBMSCs massively migrate to corneal tissues after subconjunctival injection. Both macroscopic and histopathological examination showed minimal or no evidence of GVHD in the right eye, while the left eye, where no hBMSCs were injected, displayed features of GVHD. Thus, in the current study, we confirm that hBMSCs may induce their therapeutic effect at least in part by differentiation and regeneration of damaged tissues in the host. Our results provide experimental evidence that hBMSCs represent a potential cellular therapy to attenuate oGVHD.

  6. Role of intestinal epithelial cells in the host secretory response to infection by invasive bacteria. Bacterial entry induces epithelial prostaglandin h synthase-2 expression and prostaglandin E2 and F2alpha production.

    PubMed Central

    Eckmann, L; Stenson, W F; Savidge, T C; Lowe, D C; Barrett, K E; Fierer, J; Smith, J R; Kagnoff, M F

    1997-01-01

    Increased intestinal fluid secretion is a protective host response after enteric infection with invasive bacteria that is initiated within hours after infection, and is mediated by prostaglandin H synthase (PGHS) products in animal models of infection. Intestinal epithelial cells are the first host cells to become infected with invasive bacteria, which enter and pass through these cells to initiate mucosal, and ultimately systemic, infection. The present studies characterized the role of intestinal epithelial cells in the host secretory response after infection with invasive bacteria. Infection of cultured human intestinal epithelial cell lines with invasive bacteria, but not noninvasive bacteria, is shown to induce the expression of one of the rate-limiting enzymes for prostaglandin formation, PGHS-2, and the production of PGE2 and PGF2alpha. Furthermore, increased PGHS-2 expression was observed in intestinal epithelial cells in vivo after infection with invasive bacteria, using a human intestinal xenograft model in SCID mice. In support of the physiologic importance of epithelial PGHS-2 expression, supernatants from bacteria-infected intestinal epithelial cells were shown to increase chloride secretion in an in vitro model using polarized epithelial cells, and this activity was accounted for by PGE2. These studies define a novel autocrine/paracrine function of mediators produced by intestinal epithelial cells in the rapid induction of increased fluid secretion in response to intestinal infection with invasive bacteria. PMID:9218506

  7. Initial Symbiont Contact Orchestrates Host Organ-wide Transcriptional Changes that Prime Tissue Colonization

    PubMed Central

    Kremer, Natacha; Philipp, Eva E.R.; Carpentier, Marie-Christine; Brennan, Caitlin A.; Kraemer, Lars; Altura, Melissa A.; Augustin, René; Häsler, Robert; Heath-Heckman, Elizabeth A. C.; Peyer, Suzanne M.; Schwartzman, Julia; Rader, Bethany; Ruby, Edward G.; Rosenstiel, Philip; McFall-Ngai, Margaret J.

    2013-01-01

    SUMMARY Upon transit to colonization sites, bacteria often experience critical priming that prepares them for subsequent, specific interactions with the host; however, the underlying mechanisms are poorly described. During initiation of the symbiosis between the bacterium Vibrio fischeri and its squid host, which can be observed directly and in real time, ~5 V. fischeri cells aggregate along the mucociliary membranes of a superficial epithelium prior to entering host tissues. Here we show that these few early host-associated symbionts specifically induce robust changes in host gene expression that are critical to subsequent colonization steps. This exquisitely sensitive response to its specific symbiotic partner includes the upregulation of a host endochitinase, whose activity hydrolyzes polymeric chitin in the mucus into chitobiose, thereby priming the symbiont and also producing a chemoattractant gradient that promotes V. fischeri migration into host tissues. Thus, the host responds transcriptionally upon initial symbiont contact, which facilitates subsequent colonization. PMID:23954157

  8. Tissue-engineered skin preserving the potential of epithelial cells to differentiate into hair after grafting.

    PubMed

    Larouche, Danielle; Cuffley, Kristine; Paquet, Claudie; Germain, Lucie

    2011-03-01

    The aim of this study was to evaluate whether tissue-engineered skin produced in vitro was able to sustain growth of hair follicles in vitro and after grafting. Different tissues were designed. Dissociated newborn mouse keratinocytes or newborn mouse hair buds (HBs) were added onto dermal constructs consisting of a tissue-engineered cell-derived matrix elaborated from either newborn mouse or adult human fibroblasts cultured with ascorbic acid. After 7-21 days of maturation at the air-liquid interface, no hair was noticed in vitro. Epidermal differentiation was observed in all tissue-engineered skin. However, human fibroblast-derived tissue-engineered dermis (hD) promoted a thicker epidermis than mouse fibroblast-derived tissue-engineered dermis (mD). In association with mD, HBs developed epithelial cyst-like inclusions presenting outer root sheath-like attributes. In contrast, epidermoid cyst-like inclusions lined by a stratified squamous epithelium were present in tissues composed of HBs and hD. After grafting, pilo-sebaceous units formed and hair grew in skin elaborated from HBs cultured 10-26 days submerged in culture medium in association with mD. However, the number of normal hair follicles decreased with longer culture time. This hair-forming capacity after grafting was not observed in tissues composed of hD overlaid with HBs. These results demonstrate that epithelial stem cells can be kept in vitro in a permissive tissue-engineered dermal environment without losing their potential to induce hair growth after grafting.

  9. Homeostatic pressure, tumor growth and fingering of epithelial tissues: Some generic physics arguments

    NASA Astrophysics Data System (ADS)

    Risler, Thomas

    2011-03-01

    We propose that one aspect of homeostasis is the regulation of tissues to preferred pressures, which can lead to a competition for space of purely mechanical origin and be an underlying mechanism for tumor growth. Surface and bulk contributions to pressure lead to the existence of a critical size that must be overcome by metastases to reach macroscopic sizes. This property qualitatively explains the observed size distributions of metastases, while size-independent growth rates cannot account for clinical and experimental data. It also potentially explains the observed preferential growth of metastases on tissue surfaces and membranes, suggests a mechanism underlying the seed and soil hypothesis introduced by Stephen Paget in 1889, and yields realistic values for metastatic inefficiency. Treating epithelial tissues as viscous fluids with effective cell division, we find a novel hydrodynamic instability that leads to the formation of fingering protrusions of the epithelium into the connective tissue. Arising from a combination of viscous friction effects and proliferation of the epithelial cells, this instability provides physical insight into a potential mechanism by which interfaces between epithelia and stroma undulate, and potentially by which tissue dysplasia leads to cancerous invasion. In collaboration with M. Basan, J.-F. Joanny, X. Sastre-Garau and J. Prost.

  10. Relative resistance of long junctional epithelial adhesions and connective tissue attachments to plaque-induced inflammation.

    PubMed

    Beaumont, R H; O'Leary, T J; Kafrawy, A H

    1984-04-01

    This study compared the resistance to periodontal disease of the long junctional epithelial adhesion and the naturally occurring dentogingival junction. Two groups were used, each containing three young male beagle dogs with all permanent teeth erupted. Periodontitis was induced around maxillary and mandibular premolars in the experimental dogs over a 42-day period, using subgingival ligatures and a soft diet. Fourteen days after ligature removal, flaps were reflected, granulation tissue was removed and the roots were planed to the alveolar crest. Reference grooves were placed in the root surfaces at the level of the alveolar bone, the flaps were positioned over the alveolar crests, and sutures were placed. A 60-day period permitted healing with formation of long junctional epithelial adhesions. During this 116-day period control dogs were maintained in gingival health by daily brushing and by prophylaxis every 14 days. Both groups had a high level of health (GI scores of 0) at the beginning of the 20-day combined disease phase. Inflammation was induced in both groups by subgingival ligature placement and a plaque-promoting diet. Right and left sides of both groups represented separate time intervals within the 20-day period. Block sections were secured at time of killing and the tissues were prepared for light and fluorescent microscopic evaluation. Mean GI scores and mean probing depths increased similarly in both groups. Tagge index scores of gingival inflammation were higher at the longer time periods in the experimental animals. However, they displayed an intact long junctional epithelial adhesion throughout the study, while control animals frequently showed ulceration of the sulcular epithelium. Neither group showed significant changes in location of the apical cells of the attachment epithelium. Crestal osteoblastic activity, confirmed with Procion labeling, predominated in the experimental animals, while osteoclastic activity predominated in the control

  11. Using organotypic (raft) epithelial tissue cultures for the biosynthesis and isolation of infectious human papillomaviruses

    PubMed Central

    Ozbun, Michelle A.; Patterson, Nicole A.

    2014-01-01

    Papillomaviruses have a strict tropism for epithelial cells and they are fully reliant on cellular differentiation for completion of their life cycles, resulting in the production of progeny virions. Thus, a permissive environment for full viral replication in vitro wherein virion morphogenesis occurs under cooperative viral and cellular cues requires the cultivation of epithelium. Presented in the first section of this unit is a protocol for growing differentiating epithelial tissues, whose structure and function mimics many important morphological and biochemical aspects of normal skin. The technique, pioneered by Asslineau and Pruniéras (Asselineau and Prunieras 1984) and modified by Kopan et al. (Kopan et al. 1987), involves growing epidermal cells atop a dermal equivalent consisting of live fibroblasts and a collagen lattice. Epithelial stratification and differentiation ensues when the keratinocyte-dermal equivalent is placed at the air-liquid interface. The apparent floating nature of the cell-matrix in this method led to the nickname “raft” cultures. The general technique can be applied to normal low passage keratinocytes, to cells stably transfected with papillomavirus genes or genomes, as well as keratinocytes established from neoplastic lesions. However, infectious papillomavirus particles have only been isolated from organotypic epithelial cultures initiated with cells that maintain oncogenic human papillomavirus genomes in an extrachomosomal replicative form. The second section of this unit is dedicated to a virion isolation method that minimizes aerosol and skin exposure to these human carcinogens. Although the focus of the protocols is on the growth of tissues that yields infectious papillomavirus progeny, this culture system facilitates the investigation of these fastidious viruses during their complex replicative cycles, and raft tissues can be manipulated and harvested at any point during the process. Importantly, a single step virus growth

  12. Using organotypic (raft) epithelial tissue cultures for the biosynthesis and isolation of infectious human papillomaviruses.

    PubMed

    Ozbun, Michelle A; Patterson, Nicole A

    2014-08-01

    Papillomaviruses have a strict tropism for epithelial cells, and they are fully reliant on cellular differentiation for completion of their life cycles, resulting in the production of progeny virions. Thus, a permissive environment for full viral replication in vitro-wherein virion morphogenesis occurs under cooperative viral and cellular cues-requires the cultivation of epithelium. Presented in the first section of this unit is a protocol to grow differentiating epithelial tissues that mimic many important morphological and biochemical aspects of normal skin. The technique involves growing epidermal cells atop a dermal equivalent consisting of live fibroblasts and a collagen lattice. Epithelial stratification and differentiation ensues when the keratinocyte-dermal equivalent is placed at the air-liquid interface. The apparent floating nature of the cell-matrix in this method led to the nickname "raft" cultures. The general technique can be applied to normal low passage keratinocytes, to cells stably transfected with papillomavirus genes or genomes, or keratinocytes established from neoplastic lesions. However, infectious papillomavirus particles have only been isolated from organotypic epithelial cultures initiated with cells that maintain oncogenic human papillomavirus genomes in an extrachomosomal replicative form. The second section of this unit is dedicated to a virion isolation method that minimizes aerosol and skin exposure to these human carcinogens. Although the focus of the protocols is on the growth of tissues that yields infectious papillomavirus progeny, this culture system facilitates the investigation of these fastidious viruses during their complex replicative cycles, and raft tissues can be manipulated and harvested at any point during the process. Importantly, a single-step virus growth cycle is achieved in this process, as it is unlikely that progeny virions are released to initiate subsequent rounds of infection.

  13. Noninvasive method of DNA isolation from fecal epithelial tissue of dairy animals.

    PubMed

    Chandra De, Bidhan; Patra, Mahesh Chandra; Kumar, Sushil; Brahma, Biswajit; Goutam, Devika; Jaiswal, Latika; Sharma, Ashutosh; De, Sachinandan

    2015-01-01

    A novel noninvasive genomic DNA isolation protocol from fecal tissue, by the proteinase K digestion and guanidine hydrochloride extraction method, was assessed for the genotyping of cattle and buffalo. The epithelial tissues present on the surface of the feces were used as source for isolation of genomic DNA. The DNA isolated from fecal tissue was found to be similar as those obtained from other body tissues such as skin, brain, liver, kidney, and muscle. The quality of DNA was checked by agarose gel electrophoresis and polymerase chain reaction (PCR). We successfully amplified a 320 bp MHC class II DRB gene and a 125 bp mt-DNA D-loop region from isolated genomic DNA of cattle. Thus, the DNA isolated using this method was suitable for common molecular biology methods, such as restriction enzyme digestion and genotyping of dairy animals through PCR.

  14. Experimental evaluation of angularly-variable fiber geometry for targeting depth-resolved reflectance from layered epithelial tissue phantoms

    NASA Astrophysics Data System (ADS)

    Wang, Adrien; Nammalvar, Vengadesan; Drezek, Rebekah

    2007-02-01

    The aim of the present study focuses on experimentally demonstrating the efficacy of using angularly-variable fiber geometry to achieve the desired tissue-layer selection and probing depths with the further objective of enhancing the sensitivity and specificity of spectral diagnosis in stratified architectures that resemble human cervical epithelia. The morphological and biochemical features of epithelial tissue vary in accordance with tissue depths; consequently, the accuracy of spectroscopic diagnosis of epithelial dysplasia may be enhanced by probing the optical properties of this tissue. When correlated to cellular dysplasia, layer-specific changes in tissue optical properties may be deciphered by reflectance spectroscopy coupled with angularly-variable fiber geometry. This study addresses the utility of using such angularly-variable fiber geometry for resolving spatially-specific spectral signatures of tissue pathology. This is accomplished by interpreting and analyzing the reflectance spectra of increasingly dysplastic epithelial tissue in two-layer epithelial phantoms. Spectral sensitivity to tissue abnormalities in the epithelial layer is significantly improved as the obliquity of the collection fibers increases from 0 to 40 degrees. Conversely, conventionally orthogonal fibers are found to be more sensitive to changes in stromal tissue properties.

  15. Evidence from a mouse model that epithelial cell migration and mesenchymal-epithelial transition contribute to rapid restoration of uterine tissue integrity during menstruation.

    PubMed

    Cousins, Fiona L; Murray, Alison; Esnal, Arantza; Gibson, Douglas A; Critchley, Hilary O D; Saunders, Philippa T K

    2014-01-01

    In women dynamic changes in uterine tissue architecture occur during each menstrual cycle. Menses, characterised by the shedding of the upper functional layer of the endometrium, is the culmination of a cascade of irreversible changes in tissue function including stromal decidualisation, inflammation and production of degradative enzymes. The molecular mechanisms that contribute to the rapid restoration of tissue homeostasis at time of menses are poorly understood. A modified mouse model of menses was developed to focus on the events occurring within the uterine lining during endometrial shedding/repair. Decidualisation, vaginal bleeding, tissue architecture and cell proliferation were evaluated at 4, 8, 12, and 24 hours after progesterone (P4) withdrawal; mice received a single injection of bromodeoxyuridine (BrdU) 90 mins before culling. Expression of genes implicated in the regulation of mesenchymal to epithelial transition (MET) was determined using a RT2 PCR profiler array, qRTPCR and bioinformatic analysis. Mice exhibited vaginal bleeding between 4 and 12 hours after P4 withdrawal, concomitant with detachment of the decidualised cell mass from the basal portion of the endometrial lining. Immunostaining for BrdU and pan cytokeratin revealed evidence of epithelial cell proliferation and migration. Cells that appeared to be in transition from a mesenchymal to an epithelial cell identity were identified within the stromal compartment. Analysis of mRNAs encoding genes expressed exclusively in the epithelial or stromal compartments, or implicated in MET, revealed dynamic changes in expression, consistent with a role for reprogramming of mesenchymal cells so that they could contribute to re-epithelialisation. These studies have provided novel insights into the cellular processes that contribute to re-epithelialisation post-menses implicating both epithelial cell migration and mesenchymal cell differentiation in restoration of an intact epithelial cell layer. These

  16. Pro-inflammatory Cytokines Impair Vitamin D-induced Host Defense in Cultured Airway Epithelial Cells.

    PubMed

    Schrumpf, Jasmijn A; Amatngalim, Gimano D; Veldkamp, Joris B; Verhoosel, Renate M; Ninaber, Dennis K; Ordonez, Soledad R; van der Does, Anne M; Haagsman, Henk P; Hiemstra, Pieter S

    2017-02-23

    Vitamin D is a regulator of host defense against infections and induces expression of the antimicrobial peptide hCAP18/LL-37. Vitamin D deficiency is associated with chronic inflammatory lung diseases and respiratory infections. However, it is incompletely understood if and how (chronic) airway inflammation affects vitamin D metabolism and action. We hypothesized that long-term exposure of primary bronchial epithelial cells (PBEC) to pro-inflammatory cytokines alters their vitamin D metabolism, antibacterial activity and expression of hCAP18/LL-37. To investigate this, PBEC were differentiated at the air-liquid interphase for 14 days in presence of the pro-inflammatory cytokines TNF-α and IL-1β (TNF-α/IL-1β), and subsequently exposed to vitamin D (inactive 25(OH)D3 and active 1,25(OH)2D3). Expression of hCAP18/LL-37, vitamin D receptor (VDR) and enzymes involved in vitamin D metabolism (CYP24A1 and CYP27B1) was determined using qPCR, Western blot and immunofluorescence staining. Furthermore, vitamin D-mediated antibacterial activity was assessed using non-typeable Haemophilus influenzae (NTHi). We found that TNF-α/IL-1β treatment reduced vitamin D-induced expression of hCAP18/LL-37 and killing of NTHi. In addition, CYP24A1 (a vitamin D-degrading enzyme) was increased by TNF-α/IL-1β, whereas CYP27B1 (that converts 25(OH)D3 to its active form) and VDR expression remained unaffected. Furthermore, we demonstrated that the TNF-α/IL-1β-mediated induction of CYP24A1 was at least in part mediated by the transcription factor specific protein 1 (Sp1) and the EGFR-MAPK-pathway. These findings indicate that TNF-α/IL-1β decreases vitamin D-mediated antibacterial activity and hCAP18/LL-37 expression via induction of CYP24A1, and suggests that chronic inflammation impairs protective responses induced by vitamin D.

  17. Pathogen and host differences in bacterial adherence to human buccal epithelial cells in a northeast Brazilian community.

    PubMed Central

    Walser, B L; Newman, R D; Lima, A A; Guerrant, R L

    1992-01-01

    The adherence of several strains of Escherichia coli to human buccal epithelial cells was studied, using cells obtained from five groups: healthy adults, healthy children, children with acute diarrhea, children with persistent diarrhea associated with cryptosporidial parasites, and children with noncryptosporidial persistent diarrhea. All groups lived or worked in an urban slum in northeastern Brazil. Samples of buccal epithelial cells from subjects in each of these groups were incubated with wild-type E. coli K-12 (strain C600), the enteroaggregative E. coli strains 17-2 and PDAS 30-5, CFA/II-positive E. coli 1392+ and its plasmid-cured derivative 1392-, and hydrophobic E. coli 132-3. Samples were evaluated microscopically to determine background contamination and the percentage of cells with more than 15% of their surface area obscured by adherent bacteria after incubation and washing. The assay was tested under field conditions and was shown to produce reliable and consistent results. Both enteroaggregative strains of E. coli were shown to adhere to a significantly higher percentage of all groups of human buccal epithelial cells than any of the other tested strains. In addition, buccal epithelial cells from children with nonparasitic persistent diarrhea showed substantially more bacterial adherence in both the native state and with all tested strains of E. coli than did cells from children with persistent cryptosporidial diarrhea or acute diarrhea or from healthy controls. This study provides evidence that enteroaggregative strains of E. coli demonstrate increased adherence to human buccal epithelial cells (as well as to cultured HEp-2 cells) and that buccal epithelial cells from children with noncryptosporidial persistent diarrhea appear to be more susceptible to bacterial adherence and colonization than buccal epithelial cells from control groups. These findings suggest that host differences as well as pathogen differences are important in the pathogenesis of

  18. The Respiratory Pathogen Moraxella catarrhalis Targets Collagen for Maximal Adherence to Host Tissues

    PubMed Central

    Singh, Birendra; Alvarado-Kristensson, Maria; Johansson, Martin; Hallgren, Oskar; Westergren-Thorsson, Gunilla; Mörgelin, Matthias

    2016-01-01

    ABSTRACT Moraxella catarrhalis is a human respiratory pathogen that causes acute otitis media in children and is associated with exacerbations in patients suffering from chronic obstructive pulmonary disease (COPD). The first step in M. catarrhalis colonization is adherence to the mucosa, epithelial cells, and extracellular matrix (ECM). The objective of this study was to evaluate the role of M. catarrhalis interactions with collagens from various angles. Clinical isolates (n = 43) were tested for collagen binding, followed by a detailed analysis of protein-protein interactions using recombinantly expressed proteins. M. catarrhalis-dependent interactions with collagen produced by human lung fibroblasts and tracheal tissues were studied by utilizing confocal immunohistochemistry and high-resolution scanning electron microscopy. A mouse smoke-induced chronic obstructive pulmonary disease (COPD) model was used to estimate the adherence of M. catarrhalis in vivo. We found that all M. catarrhalis clinical isolates tested adhered to fibrillar collagen types I, II, and III and network-forming collagens IV and VI. The trimeric autotransporter adhesins ubiquitous surface protein A2 (UspA2) and UspA2H were identified as major collagen-binding receptors. M. catarrhalis wild type adhered to human tracheal tissue and collagen-producing lung fibroblasts, whereas UspA2 and UspA2H deletion mutants did not. Moreover, in the COPD mouse model, bacteria devoid of UspA2 and UspA2H had a reduced level of adherence to the respiratory tract compared to the adherence of wild-type bacteria. Our data therefore suggest that the M. catarrhalis UspA2 and UspA2H-dependent interaction with collagens is highly critical for adherence in the host and, furthermore, may play an important role in the establishment of disease. PMID:27006460

  19. Role of the epithelial cell rests of Malassez in the development, maintenance and regeneration of periodontal ligament tissues.

    PubMed

    Xiong, Jimin; Gronthos, Stan; Bartold, P Mark

    2013-10-01

    Periodontitis is a highly prevalent inflammatory disease that results in damage to the tooth-supporting tissues, potentially leading to tooth loss. Periodontal tissue regeneration is a complex process that involves the collaboration of two hard tissues (cementum and alveolar bone) and two soft tissues (gingiva and periodontal ligament). To date, no periodontal-regenerative procedures provide predictable clinical outcomes. To understand the rational basis of regenerative procedures, a better understanding of the events associated with the formation of periodontal components will help to establish reliable strategies for clinical practice. An important aspect of this is the role of the Hertwig's epithelial root sheath in periodontal development and that of its descendants, the epithelial cell rests of Malassez, in the maintenance of the periodontium. An important structure during tooth root development, the Hertwig's epithelial root sheath is not only a barrier between the dental follicle and dental papilla cells but is also involved in determining the shape, size and number of roots and in the development of dentin and cementum, and may act as a source of mesenchymal progenitor cells for cementoblasts. In adulthood, the epithelial cell rests of Malassez are the only odontogenic epithelial population in the periodontal ligament. Although there is no general agreement on the functions of the epithelial cell rests of Malassez, accumulating evidence suggests that the putative roles of the epithelial cell rests of Malassez in adult periodontal ligament include maintaining periodontal ligament homeostasis to prevent ankylosis and maintain periodontal ligament space, to prevent root resorption, to serve as a target during periodontal ligament innervation and to contribute to cementum repair. Recently, ovine epithelial cell rests of Malassez cells have been shown to harbor clonogenic epithelial stem-cell populations that demonstrate similar properties to mesenchymal stromal

  20. Rapamycin regulates connective tissue growth factor expression of lung epithelial cells via phosphoinositide 3-kinase.

    PubMed

    Xu, Xuefeng; Wan, Xuan; Geng, Jing; Li, Fei; Yang, Ting; Dai, Huaping

    2013-09-01

    The pathogenesis of idiopathic pulmonary fibrosis (IPF) remains largely unknown. It is believed that IPF is mainly driven by activated alveolar epithelial cells that have a compromised migration capacity, and that also produce substances (such as connective tissue growth factor, CTGF) that contribute to fibroblast activation and matrix protein accumulation. Because the mechanisms regulating these processes are unclear, the aim of this study was to determine the role of rapamycin in regulating epithelial cell migration and CTGF expression. Transformed epithelial cell line A549 and normal human pulmonary alveolar or bronchial epithelial cells were cultured in regular medium or medium containing rapamycin. Real time reverse transcriptase polymerase chain reaction was employed to determine CTGF mRNA expression. Western blotting and an enzyme-linked immunosorbent assay were used for detecting CTGF protein. Wound healing and migration assays were used to determine the cell migration potential. Transforming growth factor (TGF)-β type I receptor (TβRI) inhibitor, SB431542 and phosphoinositide 3-kinase (PI3K) inhibitor, LY294002 were used to determine rapamycin's mechanism of action. It was found that treatment of A549 and normal human alveolar or bronchial epithelial cells with rapamycin significantly promoted basal or TGF-β1 induced CTGF expression. LY294002, not SB431542 attenuated the promotional effect of rapamycin on CTGF expression. Cell mobility was not affected by rapamycin in wound healing and migration assays. These data suggest rapamycin has a profibrotic effect in vitro and underscore the potential of combined therapeutic approach with PI3K and mammalian target of rapamycin inhibitors for the treatment of animal or human lung fibrosis.

  1. Value of human amniotic epithelial cells in tissue engineering for cornea.

    PubMed

    Fatimah, Simat Siti; Ng, Sook Luan; Chua, Kien Hui; Hayati, Abdul Rahman; Tan, Ay Eeng; Tan, Geok Chin

    2010-11-01

    Human amniotic epithelial cells (hAECs) are potentially one of the key players in tissue engineering due to their easy availability. The aim of the present study was to develop an optimal isolation and transportation technique, as well as to determine the immunophenotype and epithelial gene expression of hAECs. Amnion was mechanically peeled off from the chorion and digested with trypsin-ethylenediaminetetraacetic acid. The isolated hAECs were cultured in medium containing 10 ng/mL epidermal growth factor until P4. The epithelial gene expression, cell surface antigen and protein expression of hAECs were analyzed by quantitative polymerase chain reaction, flow cytometry and immunocytochemistry. hAECs were also cultured in adipogenic, osteogenic and neurogenic induction media. The best cell yield of hAECs was seen in the digestion of 15 pieces of amnion (2 × 2 cm) and isolated 30 min after digestion with trypsin. F12:Dulbecco's modified eagle medium was the best medium for short term storage at 4 °C. hAECs expressed CD9, CD44, CD73 and CD90, and negligibly expressed CD31, CD34, CD45 and CD117. After serial passage, CK3, CK19 and involucrin gene expressions were upregulated, while p63, CK1 and CK14 gene expressions were downregulated. Sustained gene expressions of integrin β1 and CK18 were observed. At initial culture, these cells might have stem-like properties. However, they differentiated after serial passage. Nonetheless, hAECs have epithelial stem cell characteristics and have the potential to differentiate into corneal epithelial cells. Further investigations are still needed to elucidate the mechanism of differentiation involved and to optimize the culture condition for long term in vitro culture.

  2. Lung epithelial GM-CSF improves host defense function and epithelial repair in influenza virus pneumonia-a new therapeutic strategy?

    PubMed

    Rösler, Barbara; Herold, Susanne

    2016-12-01

    Influenza viruses (IVs) circulate seasonally and are a common cause of respiratory infections in pediatric and adult patients. Additionally, recurrent pandemics cause massive morbidity and mortality worldwide. Infection may result in rapid progressive viral pneumonia with fatal outcome. Since accurate treatment strategies are still missing, research refocuses attention to lung pathology and cellular crosstalk to develop new therapeutic options.Alveolar epithelial cells (AECs) play an important role in orchestrating the pulmonary antiviral host response. After IV infection they release a cascade of immune mediators, one of which is granulocyte and macrophage colony-stimulating factor (GM-CSF). GM-CSF is known to promote differentiation, activation and mobilization of myeloid cells. In the lung, GM-CSF drives immune functions of alveolar macrophages and dendritic cells (DCs) and also improves epithelial repair processes through direct interaction with AECs. During IV infection, AEC-derived GM-CSF shows a lung-protective effect that is also present after local GM-CSF application. This mini-review provides an overview on GM-CSF-modulated immune responses to IV pneumonia and its therapeutic potential in severe IV pneumonia.

  3. Controlled surface topography regulates collective 3D migration by epithelial-mesenchymal composite embryonic tissues.

    PubMed

    Song, Jiho; Shawky, Joseph H; Kim, YongTae; Hazar, Melis; LeDuc, Philip R; Sitti, Metin; Davidson, Lance A

    2015-07-01

    Cells in tissues encounter a range of physical cues as they migrate. Probing single cell and collective migratory responses to physically defined three-dimensional (3D) microenvironments and the factors that modulate those responses are critical to understanding how tissue migration is regulated during development, regeneration, and cancer. One key physical factor that regulates cell migration is topography. Most studies on surface topography and cell mechanics have been carried out with single migratory cells, yet little is known about the spreading and motility response of 3D complex multi-cellular tissues to topographical cues. Here, we examine the response to complex topographical cues of microsurgically isolated tissue explants composed of epithelial and mesenchymal cell layers from naturally 3D organized embryos of the aquatic frog Xenopus laevis. We control topography using fabricated micropost arrays (MPAs) and investigate the collective 3D migration of these multi-cellular systems in these MPAs. We find that the topography regulates both collective and individual cell migration and that dense MPAs reduce but do not eliminate tissue spreading. By modulating cell size through the cell cycle inhibitor Mitomycin C or the spacing of the MPAs we uncover how 3D topographical cues disrupt collective cell migration. We find surface topography can direct both single cell motility and tissue spreading, altering tissue-scale processes that enable efficient conversion of single cell motility into collective movement. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Host DNA Repair Proteins in Response to Pseudomonas aeruginosa in Lung Epithelial Cells and in Mice ▿

    PubMed Central

    Wu, Min; Huang, Huang; Zhang, Weidong; Kannan, Shibichakravarthy; Weaver, Andrew; Mckibben, Molynda; Herington, Danielle; Zeng, Huawei; Gao, Hongwei

    2011-01-01

    Although DNA repair proteins in bacteria are critical for pathogens' genome stability and for subverting the host defense, the role of host DNA repair proteins in response to bacterial infection is poorly defined. Here, we demonstrate, for the first time, that infection with the Gram-negative bacterium Pseudomonas aeruginosa significantly altered the expression and enzymatic activity of 8-oxoguanine DNA glycosylase (OGG1) in lung epithelial cells. Downregulation of OGG1 by a small interfering RNA strategy resulted in severe DNA damage and cell death. In addition, acetylation of OGG1 is required for host responses to bacterial genotoxicity, as mutations of OGG1 acetylation sites increased Cockayne syndrome group B (CSB) protein expression. These results also indicate that CSB may be involved in DNA repair activity during infection. Furthermore, OGG1 knockout mice exhibited increased lung injury after infection with P. aeruginosa, as demonstrated by higher myeloperoxidase activity and lipid peroxidation. Together, our studies indicate that P. aeruginosa infection induces significant DNA damage in host cells and that DNA repair proteins play a critical role in the host response to P. aeruginosa infection, serving as promising targets for the treatment of this condition and perhaps more broadly Gram-negative bacterial infections. PMID:20956573

  5. Pattern formation in fiber-reinforced tubular tissues: Folding and segmentation during epithelial growth

    NASA Astrophysics Data System (ADS)

    Ciarletta, P.; Ben Amar, M.

    2012-03-01

    Constrained growth processes in living materials result in a complex distribution of residual strains, which in certain geometries may induce a bifurcation in the elastic stability. In this work, we investigate the combined effects of growth and material anisotropy in the epithelial pattern formation of tubular tissues. In order to represent the structural organization of most organs, we adopt a strain energy density which accounts for the presence of a nonlinear reinforcement made of cross-ply fibers distributed inside a ground matrix. Using a canonical transformation in mixed polar coordinates, we transform the nonlinear elastic boundary value problem into a variational formulation, performing a straightforward derivation of the Euler-Lagrange equations for perturbations in circumferential and longitudinal directions. The corresponding curves of marginal stability are obtained numerically: the results demonstrate that both the three-dimensional distribution of residual strains and the mechanical properties of fiber reinforcements within the tissue are fundamental to determine the emergence of a specific instability pattern. In particular, different proportions of axial and circumferential residual strains can model the epithelial formation of mucosal folds in the esophagus and of plicae circulares in the small intestine. The theoretical predictions are compared with morphological data for embryonic intestinal tissues, suggesting that the volumetric growth of the epithelium can also drive the early stages of villi morphogenesis.

  6. Computer simulation of wound closure in epithelial tissues: Cell-basal-lamina adhesion

    NASA Astrophysics Data System (ADS)

    Nagai, Tatsuzo; Honda, Hisao

    2009-12-01

    The mechanism of wound closure in epithelial tissues, i.e., cell monolayer sheets, is investigated through computer simulations. A wound means an area in which some cells have been removed from the normal tissue. The vertex dynamics cell model [T. Nagai and H. Honda, Philos. Mag. B 81, 699 (2001)], which describes morphogenesis of epithelial tissues using the concepts of statistical physics, is modified and applied to the closure of small wounds without mitosis. It is shown that cell-basal-lamina adhesion governs the wound closure competing with cell-cell adhesion and cell elasticity. The simulation results reproduce the actual wound closure process qualitatively and partly quantitatively. The closing proceeds with the translation of the edges of wound polygons toward the wound center and the intermittent reduction in the number of polygon edges. Over time, the process leads to an exponential decrease in the wound area. A shape factor is introduced to describe the wound shape quantitatively and is used to examine the time variation thereof. A method for determining model parameters by comparison with the experiments is given.

  7. DNA methylation signatures of the AIRE promoter in thymic epithelial cells, thymomas and normal tissues.

    PubMed

    Kont, Vivian; Murumägi, Astrid; Tykocinski, Lars-Oliver; Kinkel, Sarah A; Webster, Kylie E; Kisand, Kai; Tserel, Liina; Pihlap, Maire; Ströbel, Philipp; Scott, Hamish S; Marx, Alexander; Kyewski, Bruno; Peterson, Pärt

    2011-12-01

    Mutations in the AIRE gene cause autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), which is associated with autoimmunity towards several peripheral organs. The AIRE protein is almost exclusively expressed in medullary thymic epithelial cells (mTEC) and CpG methylation in the promoter of the AIRE gene has been suggested to control its tissue-specific expression pattern. We found that in human AIRE-positive medullary and AIRE-negative cortical epithelium, the AIRE promoter is hypomethylated, whereas in thymocytes, the promoter had high level of CpG methylation. Likewise, in mouse mTECs the AIRE promoter was uniformly hypomethylated. In the same vein, the AIRE promoter was hypomethylated in AIRE-negative thymic epithelial tumors (thymomas) and in several peripheral tissues. Our data are compatible with the notion that promoter hypomethylation is necessary but not sufficient for tissue-specific regulation of the AIRE gene. In contrast, a positive correlation between AIRE expression and histone H3 lysine 4 trimethylation, an active chromatin mark, was found in the AIRE promoter in human and mouse TECs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Semaphorin 4D induces vaginal epithelial cell apoptosis to control mouse postnatal vaginal tissue remodeling.

    PubMed

    Ito, Takuji; Bai, Tao; Tanaka, Tetsuji; Yoshida, Kenji; Ueyama, Takashi; Miyajima, Masayasu; Negishi, Takayuki; Kawasaki, Takahiko; Takamatsu, Hyota; Kikutani, Hitoshi; Kumanogoh, Atsushi; Yukawa, Kazunori

    2015-02-01

    The opening of the mouse vaginal cavity to the skin is a postnatal tissue remodeling process that occurs at approximately five weeks of age for the completion of female genital tract maturation at puberty. The tissue remodeling process is primarily composed of a hormonally triggered apoptotic process predominantly occurring in the epithelium of the distal section of the vaginal cavity. However, the detailed mechanism underlying the apoptotic induction remains to be elucidated. In the present study, it was observed that the majority of BALB/c mice lacking the class 4 semaphorin, semaphorin 4D (Sema4D), developed imperforate vagina and hydrometrocolpos resulting in a perpetually unopened vaginal cavity regardless of a normal estrogen level comparable with that in wild‑type (WT) mice. Administration of β‑estradiol to infant Sema4D‑deficient (Sema4D‑/‑) mice did not induce precocious vaginal opening, which was observed in WT mice subjected to the same β‑estradiol administration, excluding the possibility that the closed vaginal phenotype was due to insufficient estrogen secretion at the time of vaginal opening. In order to assess the role of Sema4D in the postnatal vaginal tissue remodeling process, the expression of Sema4D and its receptor, plexin‑B1, was examined as well as the level of apoptosis in the vaginal epithelia of five‑week‑old WT and Sema4D‑/‑ mice. Immunohistochemical analyses confirmed the localization of Sema4D and plexin‑B1 in the mouse vaginal epithelia. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay and immunohistochemistry detecting activated caspase‑3 revealed significantly fewer apoptotic cells in situ in the vaginal mucosa of five‑week‑old Sema4D‑/‑ mice compared with WT mice. The addition of recombinant Sema4D to Sema4D‑/‑ vaginal epithelial cells in culture significantly enhanced apoptosis of the vaginal epithelial cells, demonstrating the apoptosis‑inducing activity of Sema4D. The

  9. Cell-cycle-associated markers and clinical outcome in human epithelial cancers: a tissue microarray study.

    PubMed

    Abdulkader, I; Sánchez, L; Cameselle-Teijeiro, J; Gude, F; Chávez, J E; López-López, R; Forteza, J; Fraga, M

    2005-12-01

    The development and progression of epithelial cancers are the result of an imbalance in signals promoting and inhibiting cellular proliferation and apoptosis. The aim of this study is to evaluate the expression of cell-cycle and apoptosis regulators and correlate them with clinical outcome in the most frequent carcinomas, in order to establish common prognostic biomarkers independent of cancer origin. Using tissue microarrays (TMAs), we have analysed the immuno-expression of Ki-67, Bcl-2, Bax, cyclin D1, cyclin D3, CDK1, CDK2, CDK6, p16, p21, and p27 in a series of 205 carcinomas of the large bowel, breast, lung and prostate (80, 73, 37 and 15 cases, respectively). By univariate analysis, positivity for p27, p16 and Bcl-2 was associated with better overall survival (P<0.0135, P<0.0442 and P<0.0001, respectively). The risk of mortality was 2.3-fold greater in patients without Bcl-2 expression. TMA immunohistochemical analysis identified a subset of epithelial cancers with overlapping alterations in cell-cycle checkpoints, apoptosis regulators and tumour suppressor pathways. We found that in most common epithelial cancers, regardless of origin, Bcl-2 appears to be the key biological factor influencing clinical behaviour.

  10. Histochemical study of apoptotic epithelial cells depending on testosterone in primary cultured rat prostatic tissues.

    PubMed

    Furuya, T; Kubo, M; Ueno, A; Fujii, Y; Baba, T; Ohno, S

    2000-04-01

    To clarify whether apoptosis can be induced in cultured rat prostatic epithelial cells, they were investigated at various time points, depending on different concentrations of testosterone. Ventral lobes of rat prostates were cultured as small pieces of tissues up to 14 days. They were examined by anti-Fas antibody immunostaining and also compared to findings revealed by in situ end-labelling (ISEL) technique. To clarify apoptotic nuclei at high resolution, the quick-freezing and deep-etching (QF-DE) method was also used, as reported before. The localization and appearance of Fas-positive cells were detected more widely and earlier than those of ISEL-positive cells, but both label-positive localizations were closely related to each other. In addition, they were detected more often in epithelial cells cultured with low testosterone concentrations. By the QF-DE method, chromatin fibers were found to be broken in spotty parts of apoptotic nuclei. We could control the concentration of testosterone in culture medium and detect the appearance of Fas antigen in cultured prostatic epithelial cells, followed by apoptotic changes. So, Fas and Fas-ligand system is one candidate for apoptosis in the prostate glands, depending on removal of hormonal testosterone.

  11. Proteome data from a host-pathogen interaction study with Staphylococcus aureus and human lung epithelial cells.

    PubMed

    Surmann, Kristin; Simon, Marjolaine; Hildebrandt, Petra; Pförtner, Henrike; Michalik, Stephan; Dhople, Vishnu M; Bröker, Barbara M; Schmidt, Frank; Völker, Uwe

    2016-06-01

    To simultaneously obtain proteome data of host and pathogen from an internalization experiment, human alveolar epithelial A549 cells were infected with Staphylococcus aureus HG001 which carried a plasmid (pMV158GFP) encoding a continuously expressed green fluorescent protein (GFP). Samples were taken hourly between 1.5 h and 6.5 h post infection. By fluorescence activated cell sorting GFP-expressing bacteria could be enriched from host cell debris, but also infected host cells could be separated from those which did not carry bacteria after contact (exposed). Additionally, proteome data of A549 cells which were not exposed to S. aureus but underwent the same sample processing steps are provided as a control. Time-resolved changes in bacterial protein abundance were quantified in a label-free approach. Proteome adaptations of host cells were monitored by comparative analysis to a stable isotope labeled cell culture (SILAC) standard. Proteins were extracted from the cells, digested proteolytically, measured by nanoLC-MS/MS, and subsequently identified by database search and then quantified. The data presented here are related to a previously published research article describing the interplay of S. aureus HG001 and human epithelial cells (Surmann et al., 2015 [1]). They have been deposited to the ProteomeXchange platform with the identifiers PRIDE: http://www.ebi.ac.uk/pride/archive/projects/PXD002384 for the S. aureus HG001 proteome dataset and PRIDE: http://www.ebi.ac.uk/pride/archive/projects/PXD002388 for the A549 proteome dataset.

  12. TRAF-4 expression in epithelial progenitor cells. Analysis in normal adult, fetal, and tumor tissues.

    PubMed Central

    Krajewska, M.; Krajewski, S.; Zapata, J. M.; Van Arsdale, T.; Gascoyne, R. D.; Berern, K.; McFadden, D.; Shabaik, A.; Hugh, J.; Reynolds, A.; Clevenger, C. V.; Reed, J. C.

    1998-01-01

    TRAF-4 was discovered because of its expression in breast cancers and is a member of the tumor necrosis factor (TNF) receptor-associated factor (TRAF) family of putative signal-transducing proteins. In vitro binding assays demonstrated that TRAF-4 interacts with the cytosolic domain of the lymphotoxin-beta receptor (LT beta R) and weakly with the p75 nerve growth factor receptor (NGFR) but not with TNFR1, TNFR2, Fas, or CD40. Immunofluorescence analysis of TRAF-4 in transfected cells demonstrated localization to cytosol but not nucleus. Immunohistochemical assays of normal human adult tissues revealed prominent cytosolic immunostaining in thymic epithelial cells and lymph node dendritic cells but not in lymphocytes or thymocytes, paralleling the reported patterns of LT beta R expression. The basal cell layer of most epithelia in the body was very strongly TRAF-4 immunopositive, including epidermis, nasopharynx, respiratory tract, salivary gland, and esophagus. Similar findings were obtained in 12- to 18-week human fetal tissue, indicating a highly restricted pattern of expression even during development in the mammary gland, epithelial cells of the terminal ducts were strongly TRAF-4 immunopositive whereas myoepithelial cells and most of the mammary epithelial cells lining the extralobular ducts were TRAF-4 immunonegative. Of 84 primary breast cancers evaluated, only 7 expressed TRAF-4. Ductal carcinoma in situ (DCIS) lesions were uniformly TRAF-4 immunonegative (n = 21). In the prostate, the basal cells were strongly immunostained for TRAF-4, whereas the secretory epithelial cells were TRAF-4 negative. Basal cells in prostate hypertrophy (n = 6) and prostatic intraepithelial neoplasia (PIN; n = 6) were strongly TRAF-4 positive, but none of the 32 primary and 16 metastatic prostate cancer specimens examined contained TRAF-4-positive malignant cells. Although also expressed in some types of mesenchymal cells, these findings suggest that TRAF-4 is a marker of normal

  13. Keratin gene expression in non-epithelial tissues. Detection with polymerase chain reaction.

    PubMed Central

    Traweek, S. T.; Liu, J.; Battifora, H.

    1993-01-01

    Keratin filament are characteristically present in epithelial cells and tumors, but have also been detected in many normal and neoplastic non-epithelial cell types using immunohistochemical techniques. To investigate the validity of this seemingly aberrant protein expression, we applied the highly sensitive polymerase chain reaction (PCR) technique to study keratin gene expression in a variety of non-epithelial tissues. Total RNA was extracted from nine samples of leiomyosarcoma, four non-Hodgkin's lymphoma, seven normal bone marrows, normal lymph node, normal peripheral blood cells, freshly isolated and cultured endothelial cells, cultured skin fibroblasts, and the myeloid leukemia cell line HL-60. Amplification primers and probes for the three most primitive keratin types (8, 18, and 19) were synthesized using published gene sequences. RNA from the breast carcinoma cell line MCF-7, known to be rich in all three keratins, was used as positive control. Concurrently run actin primers were used to confirm RNA integrity. After an initial cycle with reverse transcriptase, PCR amplification was performed for 30 cycles. Southern blots of the PCR products showed variably intense bands corresponding to keratin 8 and 18 gene products in all samples, offering conclusive evidence of keratin gene expression in cells of both stromal and hematopoietic derivation. However, keratin 19 gene transcription was not nearly so ubiquitous, being detected in normal fibroblasts and endothelial cells, two of four non-Hodgkin's lymphoma and four of nine leiomyosarcoma, but not in normal lymph node, peripheral blood cells, HL-60 cells, or any of the seven normal bone marrows examined. Dilutional experiments showed PCR to be highly sensitive in the detection of keratin 19 gene expression, capable of registering one MCF-7 cell in 10(6) HL-60 cells. These studies show that variable levels of keratin 8 and 18 gene expression may be detected by PCR in a wide variety of non-epithelial tissues

  14. Interaction between Campylobacter and intestinal epithelial cells leads to a different proinflammatory response in human and porcine host.

    PubMed

    Aguilar, Carmen; Jiménez-Marín, Ángeles; Martins, Rodrigo Prado; Garrido, Juan J

    2014-11-15

    Campylobacter jejuni and Campylobacter coli are recognized as the leading causes of human diarrheal disease throughout the development world. Unlike human beings, gastrointestinal tract of pigs are frequently colonized by Campylobacter to a high level in a commensal manner. The aim of this study was to identify the differences underlying the divergent outcome following Campylobacter challenge in porcine versus human host. In order to address this, a comparative in vitro infection model was combined with microscopy, gentamicin protection assay, ELISA and quantitative PCR techniques. Invasion assays revealed that Campylobacter invaded human cells up to 10-fold more than porcine cells (p<0.05). In addition, gene expression of proinflammatory genes encoding for IL1α, IL6, IL8, CXCL2 and CCL20 were strongly up-regulated by Campylobacter in human epithelial cell at early times of infection, whereas a very reduced cytokine gene expression was detected in porcine epithelial cells. These data indicate that Campylobacter fails to invade porcine cells compared to human cells, and this leads to a lack of proinflammatory response induction, probably due to its pathogenic or commensal behavior in human and porcine host, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Hyperactivation of oxidative mitochondrial metabolism in epithelial cancer cells in situ: visualizing the therapeutic effects of metformin in tumor tissue.

    PubMed

    Whitaker-Menezes, Diana; Martinez-Outschoorn, Ubaldo E; Flomenberg, Neal; Birbe, Ruth C; Witkiewicz, Agnieszka K; Howell, Anthony; Pavlides, Stephanos; Tsirigos, Aristotelis; Ertel, Adam; Pestell, Richard G; Broda, Paolo; Minetti, Carlo; Lisanti, Michael P; Sotgia, Federica

    2011-12-01

    We have recently proposed a new mechanism for explaining energy transfer in cancer metabolism. In this scenario, cancer cells behave as metabolic parasites, by extracting nutrients from normal host cells, such as fibroblasts, via the secretion of hydrogen peroxide as the initial trigger. Oxidative stress in the tumor microenvironment then leads to autophagy-driven catabolism, mitochondrial dys-function, and aerobic glycolysis. This, in turn, produces high-energy nutrients (such as L-lactate, ketones, and glutamine) that drive the anabolic growth of tumor cells, via oxidative mitochondrial metabolism. A logical prediction of this new "parasitic" cancer model is that tumor-associated fibroblasts should show evidence of mitochondrial dys-function (mitophagy and aerobic glycolysis). In contrast, epithelial cancer cells should increase their oxidative mitochondrial capacity. To further test this hypothesis, here we subjected frozen sections from human breast tumors to a staining procedure that only detects functional mitochondria. This method detects the in situ enzymatic activity of cytochrome C oxidase (COX), also known as Complex IV. Remarkably, cancer cells show an over-abundance of COX activity, while adjacent stromal cells remain essentially negative. Adjacent normal ductal epithelial cells also show little or no COX activity, relative to epithelial cancer cells. Thus, oxidative mitochondrial activity is selectively amplified in cancer cells. Although COX activity staining has never been applied to cancer tissues, it could now be used routinely to distinguish cancer cells from normal cells, and to establish negative margins during cancer surgery. Similar results were obtained with NADH activity staining, which measures Complex I activity, and succinate dehydrogenase (SDH) activity staining, which measures Complex II activity. COX and NADH activities were blocked by electron transport inhibitors, such as Metformin. This has mechanistic and clinical implications for

  16. Human thymic epithelial primary cells produce exosomes carrying tissue-restricted antigens

    PubMed Central

    Skogberg, Gabriel; Lundberg, Vanja; Berglund, Martin; Gudmundsdottir, Judith; Telemo, Esbjörn; Lindgren, Susanne; Ekwall, Olov

    2015-01-01

    Exosomes are nano-sized vesicles released by cells into the extracellular space and have been shown to be present in thymic tissue both in mice and in humans. The source of thymic exosomes is however still an enigma and hence it is not known whether thymic epithelial cells (TECs) are able to produce exosomes. In this work, we have cultured human TECs and isolated exosomes. These exosomes carry tissue-restricted antigens (TRAs), for example, myelin basic protein and desmoglein 3. The presence of TRAs indicates a possible role for thymic epithelium-derived exosomes in the selection process of thymocytes. The key contribution of these exosomes could be to disseminate self-antigens from the thymic epithelia, thus making them more accessible to the pool of maturing thymocytes. This would increase the coverage of TRAs within the thymus, and facilitate the process of positive and negative selection. PMID:25776846

  17. Mechanical state, material properties and continuous description of an epithelial tissue

    PubMed Central

    Bonnet, Isabelle; Marcq, Philippe; Bosveld, Floris; Fetler, Luc; Bellaïche, Yohanns; Graner, François

    2012-01-01

    During development, epithelial tissues undergo extensive morphogenesis based on coordinated changes of cell shape and position over time. Continuum mechanics describes tissue mechanical state and shape changes in terms of strain and stress. It accounts for individual cell properties using only a few spatially averaged material parameters. To determine the mechanical state and parameters in the Drosophila pupa dorsal thorax epithelium, we severed in vivo the adherens junctions around a disc-shaped domain comprising typically a hundred cells. This enabled a direct measurement of the strain along different orientations at once. The amplitude and the anisotropy of the strain increased during development. We also measured the stress-to-viscosity ratio and similarly found an increase in amplitude and anisotropy. The relaxation time was of the order of 10 s. We propose a space–time, continuous model of the relaxation. Good agreement with experimental data validates the description of the epithelial domain as a continuous, linear, visco-elastic material. We discuss the relevant time and length scales. Another material parameter, the ratio of external friction to internal viscosity, is estimated by fitting the initial velocity profile. Together, our results contribute to quantify forces and displacements, and their time evolution, during morphogenesis. PMID:22628216

  18. A novel dual-flow bioreactor simulates increased fluorescein permeability in epithelial tissue barriers.

    PubMed

    Giusti, Serena; Sbrana, Tommaso; La Marca, Margherita; Di Patria, Valentina; Martinucci, Valentina; Tirella, Annalisa; Domenici, Claudio; Ahluwalia, Arti

    2014-09-01

    Permeability studies across epithelial barriers are of primary importance in drug delivery as well as in toxicology. However, traditional in vitro models do not adequately mimic the dynamic environment of physiological barriers. Here, we describe a novel two-chamber modular bioreactor for dynamic in vitro studies of epithelial cells. The fluid dynamic environment of the bioreactor was characterized using computational fluid dynamic models and measurements of pressure gradients for different combinations of flow rates in the apical and basal chambers. Cell culture experiments were then performed with fully differentiated Caco-2 cells as a model of the intestinal epithelium, comparing the effect of media flow applied in the bioreactor with traditional static transwells. The flow increases barrier integrity and tight junction expression of Caco-2 cells with respect to the static controls. Fluorescein permeability increased threefold in the dynamic system, indicating that the stimulus induced by flow increases transport across the barrier, closely mimicking the in vivo situation. The results are of interest for studying the influence of mechanical stimuli on cells, and underline the importance of developing more physiologically relevant in vitro tissue models. The bioreactor can be used to study drug delivery, chemical, or nanomaterial toxicity and to engineer barrier tissues.

  19. The graft-versus-host reaction and immune function. I. T helper cell immunodeficiency associated with graft-versus-host-induced thymic epithelial cell damage

    SciTech Connect

    Seddik, M.; Seemayer, T.A.; Lapp, W.S.

    1984-03-01

    The injection of parental A strain lymphoid cells into adrenalectomized CBAxA F1 (BAF1) mice induced a chronic graft-versus-host (GVH) reaction resulting in T cell and B cell immunosuppression as well as thymic epithelial cell injury, but not stress-related thymic involution. Thymocytes from BAF1 mice undergoing a GVH reaction were studied for their ability to reconstitute T helper cell (TH) function and phytohemagglutinin (PHA) and concanavalin A (Con A) mitogen responses in thymectomized, irradiated, BAF1 mice reconstituted with normal syngeneic bone marrow (ATxBM). Thymocytes from BAF1 mice early after the induction of a GVH reaction (days 10-12) were as effective as normal thymocytes in reconstituting TH and mitogen responses. Thymocytes from BAF1 mice 40 or more days after the induction of a GVH reaction did not reconstitute either the TH function or PHA and Con A responses in ATxBM mice. The inability to reconstitute ATxBM mice was not due to the presence of suppressor cells contained in the thymocyte inoculum. It is proposed that GVH-induced thymic epithelial cell injury blocks or arrests normal T cell differentiation, resulting in a population of thymocytes that lack the potential to become competent T helper cells or mitogen-responsive cells when transferred into ATxBM mice. This thymic functional defect results in a permanent TH immunodeficiency in mice experiencing a chronic GVH reaction.

  20. Diffuse reflectance spectroscopy of epithelial tissue with a smart fiber-optic probe.

    PubMed

    Yu, Bing; Shah, Amy; Nagarajan, Vivek K; Ferris, Daron G

    2014-03-01

    Diffuse reflectance spectroscopy (DRS) with a fiber-optic probe can noninvasively quantify the optical properties of epithelial tissues and has shown the potential as a cost-effective, fast and sensitive tool for diagnosis of early precancerous changes in the cervix and oral cavity. However, current DRS systems are susceptible to several sources of systematic and random errors, such as uncontrolled probe-to-tissue pressure and lack of a real-time calibration that can significantly impair the measurement accuracy, reliability and validity of this technology as well as its clinical utility. In addition, such systems use bulky, high power and expensive optical components which impede their widespread use in low- and middle-income countries (LMICs) where epithelial cancer related death is disproportionately high. In this paper we report a portable, easy-to-use and low cost, yet accurate and reliable DRS device that can aid in the screening and diagnosis of oral and cervical cancer. The device uses an innovative smart fiber-optic probe to eliminate operator bias, state-of-the-art photonics components to reduce size and power consumption, and automated software to reduce the need of operator training. The device showed a mean error of 1.4 ± 0.5% and 6.8 ± 1.7% for extraction of phantom absorption and reduced scattering coefficients, respectively. A clinical study on healthy volunteers indicated that a pressure below 1.0 psi is desired for oral mucosal tissues to minimize the probe effects on tissue physiology and morphology.

  1. Diffuse reflectance spectroscopy of epithelial tissue with a smart fiber-optic probe

    PubMed Central

    Yu, Bing; Shah, Amy; Nagarajan, Vivek K.; Ferris, Daron G.

    2014-01-01

    Diffuse reflectance spectroscopy (DRS) with a fiber-optic probe can noninvasively quantify the optical properties of epithelial tissues and has shown the potential as a cost-effective, fast and sensitive tool for diagnosis of early precancerous changes in the cervix and oral cavity. However, current DRS systems are susceptible to several sources of systematic and random errors, such as uncontrolled probe-to-tissue pressure and lack of a real-time calibration that can significantly impair the measurement accuracy, reliability and validity of this technology as well as its clinical utility. In addition, such systems use bulky, high power and expensive optical components which impede their widespread use in low- and middle-income countries (LMICs) where epithelial cancer related death is disproportionately high. In this paper we report a portable, easy-to-use and low cost, yet accurate and reliable DRS device that can aid in the screening and diagnosis of oral and cervical cancer. The device uses an innovative smart fiber-optic probe to eliminate operator bias, state-of-the-art photonics components to reduce size and power consumption, and automated software to reduce the need of operator training. The device showed a mean error of 1.4 ± 0.5% and 6.8 ± 1.7% for extraction of phantom absorption and reduced scattering coefficients, respectively. A clinical study on healthy volunteers indicated that a pressure below 1.0 psi is desired for oral mucosal tissues to minimize the probe effects on tissue physiology and morphology. PMID:24688805

  2. Mesenchymal to epithelial transition during tissue homeostasis and regeneration: Patching up the Drosophila midgut epithelium.

    PubMed

    Antonello, Zeus A; Reiff, Tobias; Dominguez, Maria

    2015-01-01

    Stem cells are responsible for preserving morphology and function of adult tissues. Stem cells divide to self-renew and to generate progenitor cells to sustain cell demand from the tissue throughout the organism's life. Unlike stem cells, the progenitor cells have limited proliferation potential but have the capacity to terminally differentiate and thereby to substitute older or damaged mature cells. Recent findings indicate that adult stem cells can adapt their division kinetics dynamically to match changes in tissue demand during homeostasis and regeneration. However, cell turnover not only requires stem cell division but also needs timed differentiation of the progenitor cells, which has been much less explored. In this Extra View article, we discuss the ability of progenitor cells to actively postpone terminal differentiation in the absence of a local demand and how tissue demand activates terminal differentiation via a conserved mesenchymal-epithelial transition program revealed in our recent EMBO J paper and other published and unpublished data. The extent of the significance of these results is discussed for models of tissue dynamics during both homeostasis and regeneration.

  3. STAT3 activation in Th17 and Th22 cells controls IL-22-mediated epithelial host defense during infectious colitis.

    PubMed

    Backert, Ingo; Koralov, Sergei B; Wirtz, Stefan; Kitowski, Vera; Billmeier, Ulrike; Martini, Eva; Hofmann, Katharina; Hildner, Kai; Wittkopf, Nadine; Brecht, Katrin; Waldner, Maximilian; Rajewsky, Klaus; Neurath, Markus F; Becker, Christoph; Neufert, Clemens

    2014-10-01

    The Citrobacter rodentium model mimics the pathogenesis of infectious colitis and requires sequential contributions from different immune cell populations, including innate lymphoid cells (ILCs) and CD4(+) lymphocytes. In this study, we addressed the role of STAT3 activation in CD4(+) cells during host defense in mice against C. rodentium. In mice with defective STAT3 in CD4(+) cells (Stat3(ΔCD4)), the course of infection was unchanged during the innate lymphoid cell-dependent early phase, but significantly altered during the lymphocyte-dependent later phase. Stat3(ΔCD4) mice exhibited intestinal epithelial barrier defects, including downregulation of antimicrobial peptides, increased systemic distribution of bacteria, and prolonged reduction in the overall burden of C. rodentium infection. Immunomonitoring of lamina propria cells revealed loss of virtually all IL-22-producing CD4(+) lymphocytes, suggesting that STAT3 activation was required for IL-22 production not only in Th17 cells, but also in Th22 cells. Notably, the defective host defense against C. rodentium in Stat3(∆CD4) mice could be fully restored by specific overexpression of IL-22 through a minicircle vector-based technology. Moreover, expression of a constitutive active STAT3 in CD4(+) cells shaped strong intestinal epithelial barrier function in vitro and in vivo through IL-22, and it promoted protection from enteropathogenic bacteria. Thus, our work indicates a critical role of STAT3 activation in Th17 and Th22 cells for control of the IL-22-mediated host defense, and strategies expanding STAT3-activated CD4(+) lymphocytes may be considered as future therapeutic options for improving intestinal barrier function in infectious colitis. Copyright © 2014 by The American Association of Immunologists, Inc.

  4. Host-microbial interactions and regulation of intestinal epithelial barrier function: From physiology to pathology

    PubMed Central

    Yu, Linda Chia-Hui; Wang, Jin-Town; Wei, Shu-Chen; Ni, Yen-Hsuan

    2012-01-01

    The gastrointestinal tract is the largest reservoir of commensal bacteria in the human body, providing nutrients and space for the survival of microbes while concurrently operating mucosal barriers to confine the microbial population. The epithelial cells linked by tight junctions not only physically separate the microbiota from the lamina propria, but also secrete proinflammatory cytokines and reactive oxygen species in response to pathogen invasion and metabolic stress and serve as a sentinel to the underlying immune cells. Accumulating evidence indicates that commensal bacteria are involved in various physiological functions in the gut and microbial imbalances (dysbiosis) may cause pathology. Commensal bacteria are involved in the regulation of intestinal epithelial cell turnover, promotion of epithelial restitution and reorganization of tight junctions, all of which are pivotal for fortifying barrier function. Recent studies indicate that aberrant bacterial lipopolysaccharide-mediated signaling in gut mucosa may be involved in the pathogenesis of chronic inflammation and carcinogenesis. Our perception of enteric commensals has now changed from one of opportunistic pathogens to active participants in maintaining intestinal homeostasis. This review attempts to explain the dynamic interaction between the intestinal epithelium and commensal bacteria in disease and health status. PMID:22368784

  5. Evidence from a Mouse Model That Epithelial Cell Migration and Mesenchymal-Epithelial Transition Contribute to Rapid Restoration of Uterine Tissue Integrity during Menstruation

    PubMed Central

    Cousins, Fiona L.; Murray, Alison; Esnal, Arantza; Gibson, Douglas A.; Critchley, Hilary O. D.; Saunders, Philippa T. K.

    2014-01-01

    Background In women dynamic changes in uterine tissue architecture occur during each menstrual cycle. Menses, characterised by the shedding of the upper functional layer of the endometrium, is the culmination of a cascade of irreversible changes in tissue function including stromal decidualisation, inflammation and production of degradative enzymes. The molecular mechanisms that contribute to the rapid restoration of tissue homeostasis at time of menses are poorly understood. Methodology A modified mouse model of menses was developed to focus on the events occurring within the uterine lining during endometrial shedding/repair. Decidualisation, vaginal bleeding, tissue architecture and cell proliferation were evaluated at 4, 8, 12, and 24 hours after progesterone (P4) withdrawal; mice received a single injection of bromodeoxyuridine (BrdU) 90 mins before culling. Expression of genes implicated in the regulation of mesenchymal to epithelial transition (MET) was determined using a RT2 PCR profiler array, qRTPCR and bioinformatic analysis. Principal Findings Mice exhibited vaginal bleeding between 4 and 12 hours after P4 withdrawal, concomitant with detachment of the decidualised cell mass from the basal portion of the endometrial lining. Immunostaining for BrdU and pan cytokeratin revealed evidence of epithelial cell proliferation and migration. Cells that appeared to be in transition from a mesenchymal to an epithelial cell identity were identified within the stromal compartment. Analysis of mRNAs encoding genes expressed exclusively in the epithelial or stromal compartments, or implicated in MET, revealed dynamic changes in expression, consistent with a role for reprogramming of mesenchymal cells so that they could contribute to re-epithelialisation. Conclusions/Significance These studies have provided novel insights into the cellular processes that contribute to re-epithelialisation post-menses implicating both epithelial cell migration and mesenchymal cell

  6. Distribution of O-Acetylated Sialic Acids among Target Host Tissues for Influenza Virus

    PubMed Central

    Barnard, Karen N.; Ossiboff, Robert J.; Khedri, Zahra; Feng, Kurtis H.; Yu, Hai; Chen, Xi; Varki, Ajit

    2017-01-01

    ABSTRACT Sialic acids (Sias) are important glycans displayed on the cells and tissues of many different animals and are frequent targets for binding and modification by pathogens, including influenza viruses. Influenza virus hemagglutinins bind Sias during the infection of their normal hosts, while the encoded neuraminidases and/or esterases remove or modify the Sia to allow virion release or to prevent rebinding. Sias naturally occur in a variety of modified forms, and modified Sias can alter influenza virus host tropisms through their altered interactions with the viral glycoproteins. However, the distribution of modified Sia forms and their effects on pathogen-host interactions are still poorly understood. Here we used probes developed from viral Sia-binding proteins to detect O-acetylated (4-O-acetyl, 9-O-acetyl, and 7,9-O-acetyl) Sias displayed on the tissues of some natural or experimental hosts for influenza viruses. These modified Sias showed highly variable displays between the hosts and tissues examined. The 9-O-acetyl (and 7,9-) modified Sia forms were found on cells and tissues of many hosts, including mice, humans, ferrets, guinea pigs, pigs, horses, dogs, as well as in those of ducks and embryonated chicken egg tissues and membranes, although in variable amounts. The 4-O-acetyl Sias were found in the respiratory tissues of fewer animals, being primarily displayed in the horse and guinea pig, but were not detected in humans or pigs. The results suggest that these Sia variants may influence virus tropisms by altering and selecting their cell interactions. IMPORTANCE Sialic acids (Sias) are key glycans that control or modulate many normal cell and tissue functions while also interacting with a variety of pathogens, including many different viruses. Sias are naturally displayed in a variety of different forms, with modifications at several positions that can alter their functional interactions with pathogens. In addition, Sias are often modified or

  7. Distribution of O-Acetylated Sialic Acids among Target Host Tissues for Influenza Virus.

    PubMed

    Wasik, Brian R; Barnard, Karen N; Ossiboff, Robert J; Khedri, Zahra; Feng, Kurtis H; Yu, Hai; Chen, Xi; Perez, Daniel R; Varki, Ajit; Parrish, Colin R

    2017-01-01

    Sialic acids (Sias) are important glycans displayed on the cells and tissues of many different animals and are frequent targets for binding and modification by pathogens, including influenza viruses. Influenza virus hemagglutinins bind Sias during the infection of their normal hosts, while the encoded neuraminidases and/or esterases remove or modify the Sia to allow virion release or to prevent rebinding. Sias naturally occur in a variety of modified forms, and modified Sias can alter influenza virus host tropisms through their altered interactions with the viral glycoproteins. However, the distribution of modified Sia forms and their effects on pathogen-host interactions are still poorly understood. Here we used probes developed from viral Sia-binding proteins to detect O-acetylated (4-O-acetyl, 9-O-acetyl, and 7,9-O-acetyl) Sias displayed on the tissues of some natural or experimental hosts for influenza viruses. These modified Sias showed highly variable displays between the hosts and tissues examined. The 9-O-acetyl (and 7,9-) modified Sia forms were found on cells and tissues of many hosts, including mice, humans, ferrets, guinea pigs, pigs, horses, dogs, as well as in those of ducks and embryonated chicken egg tissues and membranes, although in variable amounts. The 4-O-acetyl Sias were found in the respiratory tissues of fewer animals, being primarily displayed in the horse and guinea pig, but were not detected in humans or pigs. The results suggest that these Sia variants may influence virus tropisms by altering and selecting their cell interactions. IMPORTANCE Sialic acids (Sias) are key glycans that control or modulate many normal cell and tissue functions while also interacting with a variety of pathogens, including many different viruses. Sias are naturally displayed in a variety of different forms, with modifications at several positions that can alter their functional interactions with pathogens. In addition, Sias are often modified or removed by

  8. Host tissues as microhabitats for Wolbachia and quantitative insights into the bacterial community in terrestrial isopods.

    PubMed

    Dittmer, J; Beltran-Bech, S; Lesobre, J; Raimond, M; Johnson, M; Bouchon, D

    2014-05-01

    Animal-bacterial symbioses are highly dynamic in terms of multipartite interactions, both between the host and its symbionts as well as between the different bacteria constituting the symbiotic community. These interactions will be reflected by the titres of the individual bacterial taxa, for example via host regulation of bacterial loads or competition for resources between symbionts. Moreover, different host tissues represent heterogeneous microhabitats for bacteria, meaning that host-associated bacteria might establish tissue-specific bacterial communities. Wolbachia are widespread endosymbiotic bacteria, infecting a large number of arthropods and filarial nematodes. However, relatively little is known regarding direct interactions between Wolbachia and other bacteria. This study represents the first quantitative investigation of tissue-specific Wolbachia-microbiota interactions in the terrestrial isopod Armadillidium vulgare. To this end, we obtained a more complete picture of the Wolbachia distribution patterns across all major host tissues, integrating all three feminizing Wolbachia strains (wVulM, wVulC, wVulP) identified to date in this host. Interestingly, the different Wolbachia strains exhibited strain-specific tissue distribution patterns, with wVulM reaching lower titres in most tissues. These patterns were consistent across different host genetic backgrounds and might reflect different co-evolutionary histories between the Wolbachia strains and A. vulgare. Moreover, Wolbachia-infected females carried higher total bacterial loads in several, but not all, tissues, irrespective of the Wolbachia strain. Taken together, this quantitative approach indicates that Wolbachia is part of a potentially more diverse bacterial community, as exemplified by the presence of highly abundant bacterial taxa in the midgut caeca of several A. vulgare populations.

  9. The effect of mechanical extension stimulation combined with epithelial cell sorting on outcomes of implanted tissue-engineered muscular urethras.

    PubMed

    Fu, Qiang; Deng, Chen-Liang; Zhao, Ren-Yan; Wang, Ying; Cao, Yilin

    2014-01-01

    Urethral defects are common and frequent disorders and are difficult to treat. Simple natural or synthetic materials do not provide a satisfactory curative solution for long urethral defects, and urethroplasty with large areas of autologous tissues is limited and might interfere with wound healing. In this study, adipose-derived stem cells were used. These cells can be derived from a wide range of sources, have extensive expansion capability, and were combined with oral mucosal epithelial cells to solve the problem of finding seeding cell sources for producing the tissue-engineered urethras. We also used the synthetic biodegradable polymer poly-glycolic acid (PGA) as a scaffold material to overcome issues such as potential pathogen infections derived from natural materials (such as de-vascular stents or animal-derived collagen) and differing diameters. Furthermore, we used a bioreactor to construct a tissue-engineered epithelial-muscular lumen with a double-layer structure (the epithelial lining and the muscle layer). Through these steps, we used an epithelial-muscular lumen built in vitro to repair defects in a canine urethral defect model (1 cm). Canine urethral reconstruction was successfully achieved based on image analysis and histological techniques at different time points. This study provides a basis for the clinical application of tissue engineering of an epithelial-muscular lumen. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Epithelial Tumors Originate in Tumor Hotspots, a Tissue-Intrinsic Microenvironment

    PubMed Central

    Tamori, Yoichiro; Suzuki, Emiko; Deng, Wu-Min

    2016-01-01

    Malignant tumors are caused by uncontrolled proliferation of transformed mutant cells that have lost the ability to maintain tissue integrity. Although a number of causative genetic backgrounds for tumor development have been discovered, the initial steps mutant cells take to escape tissue integrity and trigger tumorigenesis remain elusive. Here, we show through analysis of conserved neoplastic tumor-suppressor genes (nTSGs) in Drosophila wing imaginal disc epithelia that tumor initiation depends on tissue-intrinsic local cytoarchitectures, causing tumors to consistently originate in a specific region of the tissue. In this “tumor hotspot” where cells constitute a network of robust structures on their basal side, nTSG-deficient cells delaminate from the apical side of the epithelium and begin tumorigenic overgrowth by exploiting endogenous Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling activity. Conversely, in other regions, the “tumor coldspot” nTSG-deficient cells are extruded toward the basal side and undergo apoptosis. When the direction of delamination is reversed through suppression of RhoGEF2, an activator of the Rho family small GTPases, and JAK/STAT is activated ectopically in these coldspot nTSG-deficient cells, tumorigenesis is induced. These data indicate that two independent processes, apical delamination and JAK/STAT activation, are concurrently required for the initiation of nTSG-deficient-induced tumorigenesis. Given the conservation of the epithelial cytoarchitecture, tumorigenesis may be generally initiated from tumor hotspots by a similar mechanism. PMID:27584724

  11. Mycoplasma genitalium Infection Activates Cellular Host Defense and Inflammation Pathways in a 3-Dimensional Human Endocervical Epithelial Cell Model

    PubMed Central

    McGowin, Chris L.; Radtke, Andrea L.; Abraham, Kyle; Martin, David H.; Herbst-Kralovetz, Melissa

    2013-01-01

    Background. Because Mycoplasma genitalium is a prevalent and emerging cause of sexually transmitted infections, understanding the mechanisms by which M. genitalium elicits mucosal inflammation is an essential component to managing lower and upper reproductive tract disease syndromes in women. Methods. We used a rotating wall vessel bioreactor system to create 3-dimensional (3-D) epithelial cell aggregates to model and assess endocervical infection by M. genitalium. Results. Attachment of M. genitalium to the host cell's apical surface was observed directly and confirmed using immunoelectron microscopy. Bacterial replication was observed from 0 to 72 hours after inoculation, during which time host cells underwent ultrastructural changes, including reduction of microvilli, and marked increases in secretory vesicle formation. Using genome-wide transcriptional profiling, we identified a host defense and inflammation signature activated by M. genitalium during acute infection (48 hours after inoculation) that included cytokine and chemokine activity and secretion of factors for antimicrobial defense. Multiplex bead-based protein assays confirmed secretion of proinflammatory cytokines, several of which are involved in leukocyte recruitment and hypothesized to enhance susceptibility to human immunodeficiency type 1 infection. Conclusions. These findings provide insight into key molecules and pathways involved in innate recognition of M. genitalium and the response to acute infection in the human endocervix. PMID:23493725

  12. Rapid Expansion of Human Epithelial Stem Cells Suitable for Airway Tissue Engineering.

    PubMed

    Butler, Colin R; Hynds, Robert E; Gowers, Kate H C; Lee, Dani Do Hyang; Brown, James M; Crowley, Claire; Teixeira, Vitor H; Smith, Claire M; Urbani, Luca; Hamilton, Nicholas J; Thakrar, Ricky M; Booth, Helen L; Birchall, Martin A; De Coppi, Paolo; Giangreco, Adam; O'Callaghan, Christopher; Janes, Sam M

    2016-07-15

    Stem cell-based tracheal replacement represents an emerging therapeutic option for patients with otherwise untreatable airway diseases including long-segment congenital tracheal stenosis and upper airway tumors. Clinical experience demonstrates that restoration of mucociliary clearance in the lungs after transplantation of tissue-engineered grafts is critical, with preclinical studies showing that seeding scaffolds with autologous mucosa improves regeneration. High epithelial cell-seeding densities are required in regenerative medicine, and existing techniques are inadequate to achieve coverage of clinically suitable grafts. To define a scalable cell culture system to deliver airway epithelium to clinical grafts. Human respiratory epithelial cells derived from endobronchial biopsies were cultured using a combination of mitotically inactivated fibroblasts and Rho-associated protein kinase (ROCK) inhibition using Y-27632 (3T3+Y). Cells were analyzed by immunofluorescence, quantitative polymerase chain reaction, and flow cytometry to assess airway stem cell marker expression. Karyotyping and multiplex ligation-dependent probe amplification were performed to assess cell safety. Differentiation capacity was tested in three-dimensional tracheospheres, organotypic cultures, air-liquid interface cultures, and an in vivo tracheal xenograft model. Ciliary function was assessed in air-liquid interface cultures. 3T3-J2 feeder cells and ROCK inhibition allowed rapid expansion of airway basal cells. These cells were capable of multipotent differentiation in vitro, generating both ciliated and goblet cell lineages. Cilia were functional with normal beat frequency and pattern. Cultured cells repopulated tracheal scaffolds in a heterotopic transplantation xenograft model. Our method generates large numbers of functional airway basal epithelial cells with the efficiency demanded by clinical transplantation, suggesting its suitability for use in tracheal reconstruction.

  13. Rapid Expansion of Human Epithelial Stem Cells Suitable for Airway Tissue Engineering

    PubMed Central

    Gowers, Kate H. C.; Lee, Dani Do Hyang; Brown, James M.; Crowley, Claire; Teixeira, Vitor H.; Smith, Claire M.; Urbani, Luca; Hamilton, Nicholas J.; Thakrar, Ricky M.; Booth, Helen L.; Birchall, Martin A.; De Coppi, Paolo; Giangreco, Adam; O’Callaghan, Christopher

    2016-01-01

    Rationale: Stem cell–based tracheal replacement represents an emerging therapeutic option for patients with otherwise untreatable airway diseases including long-segment congenital tracheal stenosis and upper airway tumors. Clinical experience demonstrates that restoration of mucociliary clearance in the lungs after transplantation of tissue-engineered grafts is critical, with preclinical studies showing that seeding scaffolds with autologous mucosa improves regeneration. High epithelial cell–seeding densities are required in regenerative medicine, and existing techniques are inadequate to achieve coverage of clinically suitable grafts. Objectives: To define a scalable cell culture system to deliver airway epithelium to clinical grafts. Methods: Human respiratory epithelial cells derived from endobronchial biopsies were cultured using a combination of mitotically inactivated fibroblasts and Rho-associated protein kinase (ROCK) inhibition using Y-27632 (3T3+Y). Cells were analyzed by immunofluorescence, quantitative polymerase chain reaction, and flow cytometry to assess airway stem cell marker expression. Karyotyping and multiplex ligation-dependent probe amplification were performed to assess cell safety. Differentiation capacity was tested in three-dimensional tracheospheres, organotypic cultures, air–liquid interface cultures, and an in vivo tracheal xenograft model. Ciliary function was assessed in air–liquid interface cultures. Measurements and Main Results: 3T3-J2 feeder cells and ROCK inhibition allowed rapid expansion of airway basal cells. These cells were capable of multipotent differentiation in vitro, generating both ciliated and goblet cell lineages. Cilia were functional with normal beat frequency and pattern. Cultured cells repopulated tracheal scaffolds in a heterotopic transplantation xenograft model. Conclusions: Our method generates large numbers of functional airway basal epithelial cells with the efficiency demanded by clinical

  14. A novel porous scaffold fabrication technique for epithelial and endothelial tissue engineering.

    PubMed

    McHugh, Kevin J; Tao, Sarah L; Saint-Geniez, Magali

    2013-07-01

    Porous scaffolds have the ability to minimize transport barriers for both two- (2D) and three-dimensional tissue engineering. However, current porous scaffolds may be non-ideal for 2D tissues such as epithelium due to inherent fabrication-based characteristics. While 2D tissues require porosity to support molecular transport, pores must be small enough to prevent cell migration into the scaffold in order to avoid non-epithelial tissue architecture and compromised function. Though electrospun meshes are the most popular porous scaffolds used today, their heterogeneous pore size and intense topography may be poorly-suited for epithelium. Porous scaffolds produced using other methods have similar unavoidable limitations, frequently involving insufficient pore resolution and control, which make them incompatible with 2D tissues. In addition, many of these techniques require an entirely new round of process development in order to change material or pore size. Herein we describe "pore casting," a fabrication method that produces flat scaffolds with deterministic pore shape, size, and location that can be easily altered to accommodate new materials or pore dimensions. As proof-of-concept, pore-cast poly(ε-caprolactone) (PCL) scaffolds were fabricated and compared to electrospun PCL in vitro using canine kidney epithelium, human colon epithelium, and human umbilical vein endothelium. All cell types demonstrated improved morphology and function on pore-cast scaffolds, likely due to reduced topography and universally small pore size. These results suggest that pore casting is an attractive option for creating 2D tissue engineering scaffolds, especially when the application may benefit from well-controlled pore size or architecture.

  15. A novel regulatory role for tissue transglutaminase in epithelial-mesenchymal transition in cystic fibrosis.

    PubMed

    Nyabam, Samuel; Wang, Zhuo; Thibault, Thomas; Oluseyi, Ayinde; Basar, Rameeza; Marshall, Lindsay; Griffin, Martin

    2016-09-01

    Cystic fibrosis (CF) is a genetic disorder caused by mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) for which there is no overall effective treatment. Recent work indicates tissue transglutaminase (TG2) plays a pivotal intracellular role in proteostasis in CF epithelia and that the pan TG inhibitor cysteamine improves CFTR stability. Here we show TG2 has another role in CF pathology linked with TGFβ1 activation and signalling, induction of epithelial-mesenchymal transition (EMT), CFTR stability and induction of matrix deposition. We show that increased TG2 expression in normal and CF bronchial epithelial cells increases TGFβ1 levels, promoting EMT progression, and impairs tight junctions as measured by Transepithelial Electric Resistance (TEER) which can be reversed by selective inhibition of TG2 with an observed increase in CFTR stability. Our data indicate that selective inhibition of TG2 provides a potential therapeutic avenue for reducing fibrosis and increasing CFTR stability in CF. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Construction of tissue engineered skin with human amniotic mesenchymal stem cells and human amniotic epithelial cells.

    PubMed

    Yu, S-C; Xu, Y-Y; Li, Y; Xu, B; Sun, Q; Li, F; Zhang, X-G

    2015-12-01

    To establish a new model for construction of tissue engineered skin with human amniotic mesenchymal stem cells (hAMSCs) and human amniotic epithelial cells (hAECs). hAMSCs and hAECs were isolated from amniotic membrane. The morphology and phenotype of hAMSCs and hAECs were confirmed by microscope and flow cytometry, respectively. Then, we performed RT-PCR and immunofluorescence staining to assess the expression of stem cells and keratinocyte markers. Moreover, cell co-culture was performed to observe the growth and phenotype characteristics of hAMSCs and hAECs in vitro. In addition, tissue engineered skin with hAMSCs and hAECs was constructed and assessed with histological methods. hAMSCs and hAECs were successfully isolated, exhibiting fibroblast-like morphous and cobblestone-shape epithelial morphous, respectively. The surface biomarker analysis showed that hAMSCs and hAECs were both positive for CD73, CD90 and CD105, and negative for CD34 and HLA-DR. The RT-PCR showed that hAMSCs expressed stem cell marker Nanog and c-MYC, and keratinocyte marker K19, β1 integrin and K8, whereas hAECs expressed stem cell marker KLF4 and c-MYC, and keratinocyte marker K19, β1 integrin, K5 and K8. The expression of keratinocyte proliferation antigen K14 was also found on hAECs. Furthermore, we found co-culture has no impact on the phenotype of hAMSCs and hAECs, but increased the proliferation activity of hAECs and decreased the proliferation activity of hAMSCs. Finally, the histological analysis showed that the tissue engineered skin exhibited similar structure as normal skin. Tissue engineered skin with hAMSCs and hAECs was successfully constructed and shown a similar feature as a skin equivalent. The tissue engineered skin might have good application prospects in regenerative medicine.

  17. Multimodal tissue imaging: using coregistered optical tomography data to estimate tissue autofluorescence intensity change due to scattering and absorption by neoplastic epithelial cells.

    PubMed

    Pahlevaninezhad, Hamid; Cecic, Ivana; Lee, Anthony M D; Kyle, Alastair H; Lam, Stephen; MacAulay, Calum; Lane, Pierre M

    2013-10-01

    Autofluorescence (AF) imaging provides valuable information about the structural and chemical states of tissue that can be used for early cancer detection. Optical scattering and absorption of excitation and emission light by the epithelium can significantly affect observed tissue AF intensity. Determining the effect of epithelial attenuation on the AF intensity could lead to a more accurate interpretation of AF intensity. We propose to use optical coherence tomography coregistered with AF imaging to characterize the AF attenuation due to the epithelium. We present imaging results from three vital tissue models, each consisting of a three-dimensional tissue culture grown from one of three epithelial cell lines (HCT116, OVCAR8, and MCF7) and immobilized on a fluorescence substrate. The AF loss profiles in the tissue layer show two different regimes, each approximately linearly decreasing with thickness. For thin cell cultures (<300 μm), the AF signal changes as AF(t)/AF(0)=1-1.3t (t is the thickness in millimeter). For thick cell cultures (>400 μm), the AF loss profiles have different intercepts but similar slopes. The data presented here can be used to estimate AF loss due to a change in the epithelial layer thickness and potentially to reduce AF bronchoscopy false positives due to inflammation and non-neoplastic epithelial thickening.

  18. Uptake and intracellular activity of trovafloxacin in human phagocytes and tissue-cultured epithelial cells.

    PubMed Central

    Pascual, A; García, I; Ballesta, S; Perea, E J

    1997-01-01

    The penetration of trovafloxacin into human polymorphonuclear leukocytes (PMNs), human peritoneal macrophages, and tissue-cultured epithelial cells (McCoy cells) was evaluated. The cellular concentration to extracellular concentration (C/E) ratios of trovafloxacin were greater than 9 for extracellular concentrations ranging from 0.5 to 25 micrograms/ml. The uptake of trovafloxacin by PMNs was rapid, reversible, nonsaturable, not energy dependent, and significantly increased at 4 degrees C. Ingestion of opsonized zymosan, but not opsonized Staphylococcus aureus, significantly increased the amount of PMN-associated trovafloxacin. This agent at concentrations of 0.5 and 1 microgram/ml induced a greater reduction in the survival of intracellular S. aureus in PMNs than ciprofloxacin and ofloxacin. It was concluded that trovafloxacin reaches concentrations within phagocytic and nonphagocytic cells several times higher than the extracellular ones, while it remains active in PMNs. PMID:9021179

  19. Highly Differentiated Human Airway Epithelial Cells: a Model to Study Host cell-parasite Interactions in Pertussis

    PubMed Central

    Guevara, Claudia; Zhang, Chengxian; Gaddy, Jennifer A.; Iqbal, Junaid; Guerra, Julio; Greenberg, David P.; Decker, Michael D.; Carbonetti, Nicholas; Starner, Timothy D.; McCray, Paul B.; Mooi, Frits R.

    2017-01-01

    Background Bordetella pertussis colonizes the human respiratory mucosa. Most studies on B. pertussis adherence have relied on cultured mammalian cells that lack key features present in differentiated human airway cells or on animal models that are not natural hosts of B. pertussis. The objectives of this work are to evaluate B. pertussis infection on highly differentiated human airway cells in vitro and to show the role of B. pertussis fimbriae in cell adherence. Methods Primary human airway epithelial (PHAE) cells from human bronchi and a human bronchial epithelial (HBE) cell line were grown in vitro under air-liquid interface conditions. Results PHAE and HBE cells infected with B. pertussis wild type strain revealed bacterial adherence to cell’s apical surface and bacterial induced cytoskeleton changes and cell detachment. Mutations in the major fimbrial subunits Fim2/3 or in the minor fimbrial adhesin subunit FimD affected B. pertussis adherence to predominantly HBE cells. This cell model recapitulates the morphologic features of the human airway infected by B. pertussis and confirms the role of fimbriae in B. pertussis adherence. Furthemore, HBE cells show that fimbrial subunits, and specifically FimD adhesin, are critical in B. pertussis adherence to airway cells. Conclusions The relevance of this model to study host-parasite interaction in pertussis lies in the striking physiologic and morphologic similarity between the PHAE and HBE cells and the human airway ciliated and goblet cells in vivo. These cells can proliferate in vitro, differentiate, and express the same genetic profile as human respiratory cells in vivo. PMID:26492208

  20. Chromatic confocal microscopy for multi-depth imaging of epithelial tissue

    PubMed Central

    Olsovsky, Cory; Shelton, Ryan; Carrasco-Zevallos, Oscar; Applegate, Brian E.; Maitland, Kristen C.

    2013-01-01

    We present a novel chromatic confocal microscope capable of volumetric reflectance imaging of microstructure in non-transparent tissue. Our design takes advantage of the chromatic aberration of aspheric lenses that are otherwise well corrected. Strong chromatic aberration, generated by multiple aspheres, longitudinally disperses supercontinuum light onto the sample. The backscattered light detected with a spectrometer is therefore wavelength encoded and each spectrum corresponds to a line image. This approach obviates the need for traditional axial mechanical scanning techniques that are difficult to implement for endoscopy and susceptible to motion artifact. A wavelength range of 590-775 nm yielded a >150 µm imaging depth with ~3 µm axial resolution. The system was further demonstrated by capturing volumetric images of buccal mucosa. We believe these represent the first microstructural images in non-transparent biological tissue using chromatic confocal microscopy that exhibit long imaging depth while maintaining acceptable resolution for resolving cell morphology. Miniaturization of this optical system could bring enhanced speed and accuracy to endomicroscopic in vivo volumetric imaging of epithelial tissue. PMID:23667789

  1. Chromatic confocal microscopy for multi-depth imaging of epithelial tissue.

    PubMed

    Olsovsky, Cory; Shelton, Ryan; Carrasco-Zevallos, Oscar; Applegate, Brian E; Maitland, Kristen C

    2013-05-01

    We present a novel chromatic confocal microscope capable of volumetric reflectance imaging of microstructure in non-transparent tissue. Our design takes advantage of the chromatic aberration of aspheric lenses that are otherwise well corrected. Strong chromatic aberration, generated by multiple aspheres, longitudinally disperses supercontinuum light onto the sample. The backscattered light detected with a spectrometer is therefore wavelength encoded and each spectrum corresponds to a line image. This approach obviates the need for traditional axial mechanical scanning techniques that are difficult to implement for endoscopy and susceptible to motion artifact. A wavelength range of 590-775 nm yielded a >150 µm imaging depth with ~3 µm axial resolution. The system was further demonstrated by capturing volumetric images of buccal mucosa. We believe these represent the first microstructural images in non-transparent biological tissue using chromatic confocal microscopy that exhibit long imaging depth while maintaining acceptable resolution for resolving cell morphology. Miniaturization of this optical system could bring enhanced speed and accuracy to endomicroscopic in vivo volumetric imaging of epithelial tissue.

  2. Mesenchymal-epithelial transitions: spontaneous and cumulative syntheses of epithelial marker molecules and their assemblies to novel cell junctions connecting human hematopoietic tumor cells to carcinomatoid tissue structures.

    PubMed

    Franke, Werner W; Rickelt, Steffen

    2011-12-01

    Using biochemical as well as light- and electron-microscopic immunolocalization methods, in cultures of unicellular human blood tumor cells, we have studied the phenomenon of spontaneous and cumulative syntheses of certain epithelial proteins and glycoproteins and their assemblies to two major kinds of novel cell-cell junctions, adhering junctions (AJs) and junctions based on the epithelial cell adhesion molecule (EpCAM). More than two decades, we have selected and characterized clonal sublines of multipotential hematopoietic K562 cells, which are enriched in newly formed AJs based on cis-clusters of desmoglein Dsg2, in some sublines accompanied by desmocollin Dsc2. Both desmosomal cadherins can be anchored in a submembranous plaque containing plakoglobin and plakophilins Pkp2 and Pkp3, with or without other armadillo proteins and desmoplakin. Also, these cells are often connected by an additional, extended junction system, in which the transmembrane epithelial glycoprotein EpCAM is associated with a cytoplasmic plaque rich in several actin-binding proteins such as afadin, α-actinin, ezrin and vinculin. Both kinds of junctions contribute to connections of K562 cells into epithelioid monolayers or even three-dimensional, tissue-like structures, thus markedly changing the cell biological nature and behavior of the resulting tumor subforms (mesenchymal-epithelial transitions). We discuss molecular mechanisms involved in the formation and function of these junctions, also with respect to tumor spread and metastasis, as well as diagnostic and therapeutic consequences.

  3. Interpretation and use of electrical equivalent circuits in studies of epithelial tissues.

    PubMed

    Helman, S I; Thompson, S M

    1982-12-01

    Whereas transepithelial and intracellular voltages continue to be measured in renal and other epithelial tissues, the origins of these voltages, especially in renal epithelia, remain obscure. Because epithelial tissues have multiple transcellular and extracellular routes of ion transport, it is convenient to model them with electrical equivalent circuits and, in this way, attempt to understand the relative importance of and relationships between the parallel-series arrangements of the membranes and barriers involved. The interpretation of the equivalent electromotive forces and resistances can be complicated, however, by virtue of nonlinear current-voltage relationships of ionic channels. Thus, for ion transport pathways displaying nonlinear I-V relationships, it is important to distinguish between chord and slope formalisms in the use and interpretation of electrophysiological data. For ions like Na that are generally not at electrochemical equilibrium, the Thévenin electromotive force (emf) of the slope formalism is not synonymous with the Nernst equilibrium potential of the chord formalism nor are the slope and chord conductances equal or constant at all voltages. Thus, it is mandatory that the empirical data be calculated and interpreted in a way consistent with the formalism adopted. The existence of nonlinear behavior, characterized by either Goldman or other types of rectification, exacerbates determination of relative ionic permeabilities, fractional resistances, transference numbers, and other electrophysiological parameters for simple membranes and especially for epithelia. It is argued that the use and interpretation of electrical equivalent circuits of epithelia are not arbitrary but must take into account nonlinearities of the ionic current-voltage relationships and concentration and voltage dependencies of the emfs and conductances.

  4. MUC Expression in Gallbladder Epithelial Tissues in Cholesterol-Associated Gallbladder Disease

    PubMed Central

    Yoo, Kyo-Sang; Choi, Ho Soon; Jun, Dae Won; Lee, Hang Lak; Lee, Oh Young; Yoon, Byung Chul; Lee, Kyeong Geun; Paik, Seung Sam; Kim, Yong Seok; Lee, Jin

    2016-01-01

    Background/Aims Gallstone pathogenesis is linked to mucin hypersecretion and bacterial infection. Several mucin genes have been identified in gallbladder epithelial cells (GBECs). We investigated MUC expression in cholesterol-associated gallbladder disease and evaluated the relationship between mucin and bacterial infection. Methods The present study involved 20 patients with cholesterol stones with cholecystitis, five with cholesterol stones with cholesterolosis, six with cholesterol polyps, two with gallbladder cancer, and six controls. Canine GBECs treated with lipopolysaccharide were also studied. MUC3, MUC5AC, MUC5B, and MUC6 antibodies were used for dot/slot immunoblotting and immunohistochemical studies of the gallbladder epithelial tissues, canine GBECs, and bile. Reverse-transcription polymerase chain reaction was performed to evaluate MUC3 and MUC5B expression. Results MUC3, MUC5AC, MUC5B, and MUC6 were expressed in the normal gallbladder epithelium, and of those, MUC3 and MUC5B exhibited the highest expression levels. Greatly increased levels of MUC3 and MUC5B expression were observed in the cholesterol stone group, and slightly increased levels were observed in the cholesterol polyp group; MUC3 and MUC5B mRNA was also upregulated in those groups. Canine GBECs treated with lipopolysaccharide also showed upregulation of MUC3 and MUC5B. Conclusions The mucin genes with the highest expression levels in gallbladder tissue in cholesterol-associated diseases were MUC3 and MUC5B. Cholesterol stones and gallbladder infections were associated with increased MUC3 and MUC5B expression. PMID:27563024

  5. Sugar binding to purified fractions from bovine taste buds and epithelial tissue. Relationships to bioactivity.

    PubMed

    Lum, C K; Henkin, R I

    1976-02-24

    Binding of various sugars was compared in purified subfractions of taste buds isolated from bovine circumvallate papillae and of non-taste bud-bearing epithelium isolated from tissue surrounding these papillae. Binding of 14C-labeled sugars was greater in purified subfractions obtained from taste bud than from non-taste bud-bearing tissue and was, in general, greater in those taste bud subfractions in which a greater membrane purification was achieved. Binding specificity of the 14C-labeled sugars sucrose, fructose, glucose and of 14C-labeled cyclamate and saccharine was measured by competition of each 14C-labeled sugar or synthetic sweetener with its unlabeled homologous sugar in P4(B) taste bud subfractions; this binding, as shown for sucrose, was reversible and temperature dependent. Essentially no competition of the 14C-lageled sugars sucrose, fructose, glucose or 14C-labeled cyclamate and saccharine by their respective unlabeled homologues occurred in epithelial tissue P4(B) subfractions; this binding was not reversible. Binding specificity was further observed by the competition of 14C-labeled sucrose, fructose and glucose with each unlabeled sugar for binding sites on P4(B) taste bud subfractions; unlabeled sucrose was more effective in competing with each 14C-labeled surgar than was unlabeled fructose or glucose. The relatively non-sweet sugar lactose did not compete with 14C-labeled lactose in P4(B) subfractions from either taste bud or non-taste bud-bearing epithelial tissue. Binding of 14C-labeled sucrose in purified P4(B) bud subfractions was inhibited by increased concentrations of unlabeled sucrose, phospholipase C, neuraminidase, EDTA, NaCl and urea. Dissociation constants for sugar or synthetic sweetener binding were low (approx. 10(-3) M) but in a rank order (sucrose greater than fructose greater than glucose greater than saccharine) consistent with preference and electrophysiological responses in cow. The cow is behaviorally indifferent to

  6. Comparison of human nasal epithelial cells grown as explant outgrowth cultures or dissociated tissue cultures in vitro.

    PubMed

    Jiao, Jian; Meng, Na; Wang, Hong; Zhang, Luo

    2013-12-01

    The purpose of this study was to compare cell growth characteristics, ciliated cell differentiation, and function of human nasal epithelial cells established as explant outgrowth cultures or dissociated tissue cultures. Human nasal mucosa of the uncinate process was obtained by endoscopy and epithelial cell cultures were established by explant outgrowth or dissociated tissue culture methods. Epithelial cell growth characteristics were observed by inverted phase contrast microscopy. Ciliated cell differentiation was detected by β-tubulin IVand ZO-1 immunocytochemistry. Basal and ATP-stimulated ciliary beat frequency (CBF) was measured using a highspeed digital microscopic imaging system. Both the explant and dissociated tissue cultures established as monolayers with tight junctions and differentiated cell composition, with both types of cultures comprising ciliated and non-ciliated epithelial cells. Fibroblasts were also frequently found in explant cultures but rarely seen in dissociated tissue cultures. In both culture systems, the highest ciliated cell density appeared at 7th-10th culture day and declined with time, with the lifespan of ciliated cells ranging from 14 to 21 days. Overall, 10% of the cells in explant cultures and 20% of the cells in the dissociated tissue cultures were ciliated. These two cultures demonstrated similar ciliary beat frequency values at baseline (7.78 ± 1.99 Hz and 7.91 ± 2.52 Hz, respectively) and reacted equivalently following stimulation with 100 μM ATP. The results of this study indicate that both the explant outgrowth and dissociated tissue culture techniques are suitable for growing well-differentiated nasal ciliated and non-ciliated cells, which have growth characteristics and ciliary activity similar to those of nasal epithelial cells in vivo.

  7. Philometra floridensis (Nematoda: Philometridae) damages ovarian tissue without reducing host (Sciaenops ocellatus) fecundity.

    PubMed

    Bakenhaster, Micah D; Lowerre-Barbieri, Susan; Kiryu, Yasunari; Walters, Sarah; Fajer-Avila, Emma J

    2014-04-03

    The parasitic nematode Philometra floridensis infects the ovary of its only host, the economically important fish species Sciaenops ocellatus, but the factors influencing host susceptibility and potential pathogenic effects are unknown. Here we report new information on these topics from evaluations of infected and uninfected hosts collected from the northeastern Gulf of Mexico. Fish length and age were evaluated vis-à-vis nematode prevalence to check for ontogenetic differences in host susceptibility. To evaluate health and reproductive consequences of infection, we looked for effects in Fulton's condition factor (K) and batch fecundity estimates (BF), and we evaluated ovarian tissue histologically to check for oocyte atresia and other host responses. We observed localized pathological changes in fish ovarian tissue associated with female nematodes, including leucocytic exudates, granulomatous inflammation, and Langhans-type multinucleated giant cells; the hosts, however, appeared to maintain high fecundity and actually exhibited, on average, better health index scores and higher relative fecundity than did uninfected fish. These differences are likely explained by the parasite's tendency to disproportionately infect the largest, actively spawning fish and by the localization of pathogenic changes, which could have masked effects that otherwise would have been reflected in mass-based health indicators. Although we did not detect negative effects on measures of overall health or reproductive output, further research is needed to better elucidate the relationship between these parasites and other factors affecting host reproductive potential, such as egg quality.

  8. A Helicobacter pylori Homolog of Eukaryotic Flotillin Is Involved in Cholesterol Accumulation, Epithelial Cell Responses and Host Colonization.

    PubMed

    Hutton, Melanie L; D'Costa, Kimberley; Rossiter, Amanda E; Wang, Lin; Turner, Lorinda; Steer, David L; Masters, Seth L; Croker, Ben A; Kaparakis-Liaskos, Maria; Ferrero, Richard L

    2017-01-01

    The human pathogen Helicobacter pylori acquires cholesterol from membrane raft domains in eukaryotic cells, commonly known as "lipid rafts." Incorporation of this cholesterol into the H. pylori cell membrane allows the bacterium to avoid clearance by the host immune system and to resist the effects of antibiotics and antimicrobial peptides. The presence of cholesterol in H. pylori bacteria suggested that this pathogen may have cholesterol-enriched domains within its membrane. Consistent with this suggestion, we identified a hypothetical H. pylori protein (HP0248) with homology to the flotillin proteins normally found in the cholesterol-enriched domains of eukaryotic cells. As shown for eukaryotic flotillin proteins, HP0248 was detected in detergent-resistant membrane fractions of H. pylori. Importantly, H. pylori HP0248 mutants contained lower levels of cholesterol than wild-type bacteria (P < 0.01). HP0248 mutant bacteria also exhibited defects in type IV secretion functions, as indicated by reduced IL-8 responses and CagA translocation in epithelial cells (P < 0.05), and were less able to establish a chronic infection in mice than wild-type bacteria (P < 0.05). Thus, we have identified an H. pylori flotillin protein and shown its importance for bacterial virulence. Taken together, the data demonstrate important roles for H. pylori flotillin in host-pathogen interactions. We propose that H. pylori flotillin may be required for the organization of virulence proteins into membrane raft-like structures in this pathogen.

  9. Signal transduction of Helicobacter pylori during interaction with host cell protein receptors of epithelial and immune cells

    PubMed Central

    Pachathundikandi, Suneesh Kumar; Tegtmeyer, Nicole; Backert, Steffen

    2013-01-01

    Helicobacter pylori infections can induce pathologies ranging from chronic gastritis, peptic ulceration to gastric cancer. Bacterial isolates harbor numerous well-known adhesins, vacuolating cytotoxin VacA, protease HtrA, urease, peptidoglycan, and type IV secretion systems (T4SS). It appears that H. pylori targets more than 40 known host protein receptors on epithelial or immune cells. A series of T4SS components such as CagL, CagI, CagY, and CagA can bind to the integrin α5β1 receptor. Other targeted membrane-based receptors include the integrins αvβ3, αvβ5, and β2 (CD18), RPTP-α/β, GP130, E-cadherin, fibronectin, laminin, CD46, CD74, ICAM1/LFA1, T-cell receptor, Toll-like receptors, and receptor tyrosine kinases EGFR, ErbB2, ErbB3, and c-Met. In addition, H. pylori is able to activate the intracellular receptors NOD1, NOD2, and NLRP3 with important roles in innate immunity. Here we review the interplay of various bacterial factors with host protein receptors. The contribution of these interactions to signal transduction and pathogenesis is discussed. PMID:24280762

  10. Infiltrating cells from host brain restore the microglial population in grafted cortical tissue

    PubMed Central

    Wang, Cong; Tao, Sijue; Fang, Yukun; Guo, Jing; Zhu, Lirui; Zhang, Shengxiang

    2016-01-01

    Transplantation of embryonic cortical tissue is considered as a promising therapy for brain injury. Grafted neurons can reestablish neuronal network and improve cortical function of the host brain. Microglia is a key player in regulating neuronal survival and plasticity, but its activation and dynamics in grafted cortical tissue remain unknown. Using two-photon intravital imaging and parabiotic model, here we investigated the proliferation and source of microglia in the donor region by transplanting embryonic cortical tissue into adult cortex. Live imaging showed that the endogenous microglia of the grafted tissue were rapidly lost after transplantation. Instead, host-derived microglia infiltrated and colonized the graft. Parabiotic model suggested that the main source of infiltrating cells is the parenchyma of the host brain. Colonized microglia proliferated and experienced an extensive morphological transition and eventually differentiated into resting ramified morphology. Collectively, these results demonstrated that donor tissue has little contribution to the activated microglia and host brain controls the microglial population in the graft. PMID:27615195

  11. The commensal Streptococcus salivarius K12 downregulates the innate immune responses of human epithelial cells and promotes host-microbe homeostasis.

    PubMed

    Cosseau, Celine; Devine, Deirdre A; Dullaghan, Edie; Gardy, Jennifer L; Chikatamarla, Avinash; Gellatly, Shaan; Yu, Lorraine L; Pistolic, Jelena; Falsafi, Reza; Tagg, John; Hancock, Robert E W

    2008-09-01

    Streptococcus salivarius is an early colonizer of human oral and nasopharyngeal epithelia, and strain K12 has reported probiotic effects. An emerging paradigm indicates that commensal bacteria downregulate immune responses through the action on NF-kappaB signaling pathways, but additional mechanisms underlying probiotic actions are not well understood. Our objective here was to identify host genes specifically targeted by K12 by comparing their responses with responses elicited by pathogens and to determine if S. salivarius modulates epithelial cell immune responses. RNA was extracted from human bronchial epithelial cells (16HBE14O- cells) cocultured with K12 or bacterial pathogens. cDNA was hybridized to a human 21K oligonucleotide-based array. Data were analyzed using ArrayPipe, InnateDB, PANTHER, and oPOSSUM. Interleukin 8 (IL-8) and growth-regulated oncogene alpha (Groalpha) secretion were determined by enzyme-linked immunosorbent assay. It was demonstrated that S. salivarius K12 specifically altered the expression of 565 host genes, particularly those involved in multiple innate defense pathways, general epithelial cell function and homeostasis, cytoskeletal remodeling, cell development and migration, and signaling pathways. It inhibited baseline IL-8 secretion and IL-8 responses to LL-37, Pseudomonas aeruginosa, and flagellin in epithelial cells and attenuated Groalpha secretion in response to flagellin. Immunosuppression was coincident with the inhibition of activation of the NF-kappaB pathway. Thus, the commensal and probiotic behaviors of S. salivarius K12 are proposed to be due to the organism (i) eliciting no proinflammatory response, (ii) stimulating an anti-inflammatory response, and (iii) modulating genes associated with adhesion to the epithelial layer and homeostasis. S. salivarius K12 might thereby ensure that it is tolerated by the host and maintained on the epithelial surface while actively protecting the host from inflammation and apoptosis

  12. In situ regeneration of skeletal muscle tissue through host cell recruitment.

    PubMed

    Ju, Young Min; Atala, Anthony; Yoo, James J; Lee, Sang Jin

    2014-10-01

    Standard reconstructive procedures for restoring normal function after skeletal muscle defects involve the use of existing host tissues such as muscular flaps. In many instances, this approach is not feasible and delays the rehabilitation process and restoration of tissue function. Currently, cell-based tissue engineering strategies have been used for reconstruction; however, donor tissue biopsy and ex vivo cell manipulation are required prior to implantation. The present study aimed to overcome these limitations by demonstrating mobilization of muscle cells into a target-specific site for in situ muscle regeneration. First, we investigated whether host muscle cells could be mobilized into an implanted scaffold. Poly(l-lactic acid) (PLLA) scaffolds were implanted in the tibialis anterior (TA) muscle of rats, and the retrieved scaffolds were characterized by examining host cell infiltration in the scaffolds. The host cell infiltrates, including Pax7+ cells, gradually increased with time. Second, we demonstrated that host muscle cells could be enriched by a myogenic factor released from the scaffolds. Gelatin-based scaffolds containing a myogenic factor were implanted in the TA muscle of rats, and the Pax7+ cell infiltration and newly formed muscle fibers were examined. By the second week after implantation, the Pax7+ cell infiltrates and muscle formation were significantly accelerated within the scaffolds containing insulin-like growth factor 1 (IGF-1). Our data suggest an ability of host stem cells to be recruited into the scaffolds with the capability of differentiating to muscle cells. In addition, the myogenic factor effectively promoted host cell recruitment, which resulted in accelerating muscle regeneration in situ.

  13. Protein zero, a nervous system adhesion molecule, triggers epithelial reversion in host carcinoma cells

    PubMed Central

    1995-01-01

    Protein zero (P(o)) is the immunoglobulin gene superfamily glycoprotein that mediates the self-adhesion of the Schwann cell plasma membrane that yields compact myelin. HeLa is a poorly differentiated carcinoma cell line that has lost characteristic morphological features of the cervical epithelium from which it originated. Normally, HeLa cells are not self-adherent. However, when P(o) is artificially expressed in this line, cells rapidly aggregate, and P(o) concentrates specifically at cell-cell contact sites. Rows of desmosomes are generated at these interfaces, the plasma membrane localization of cingulin and ZO-1, proteins that have been shown to be associated with tight junctions, is substantially increased, and cytokeratins coalesce into a cohesive intracellular network. Immunofluorescence patterns for the adherens junction proteins N-cadherin, alpha-catenin, and vinculin, and the desmosomal polypeptides desmoplakin, desmocollin, and desmoglein, are also markedly enhanced at the cell surface. Our data demonstrate that obligatory cell-cell adhesion, which in this case is initially brought about by the homophilic association of P(o) molecules across the intercellular cleft, triggers pronounced augmentation of the normally sluggish or sub-basal cell adhesion program in HeLa cells, culminating in suppression of the transformed state and reversion of the monolayer to an epithelioid phenotype. Furthermore, this response is apparently accompanied by an increase in mRNA and protein levels for desmoplakin and N-cadherin which are normally associated with epithelial junctions. Our conclusions are supported by analyses of ten proteins we examined immunochemically (P(o), cingulin, ZO-1, desmoplakin, desmoglein, desmocollin, N-cadherin, alpha-catenin, vinculin, and cytokeratin-18), and by quantitative polymerase chain reactions to measure relative amounts of desmoplakin and N-cadherin mRNAs. P(o) has no known signaling properties; the dramatic phenotypic changes we

  14. Examination of Epithelial Mesenchymal Transition in Keloid Tissues and Possibility of Keloid Therapy Target

    PubMed Central

    Tosa, Mamiko; Egawa, Seiko; Murakami, Masahiro; Mohammad, Ghazizadeh; Ogawa, Rei

    2016-01-01

    Background: Keloid is a fibroproliferative skin disorder that is characterized by collagen accumulation and blood vessel proliferation in the reticular layer of the dermis. It is caused by prolonged inflammation after cutaneous injury. Several studies suggested recently that epithelial mesenchymal transition (EMT) is involved in the development of fibrosis. This study assessed whether EMT also participates in keloid development and/or aggravation. Methods: Resected keloid (n = 19) and normal skin (n = 13) samples were subjected to immunohistochemical, immunofluorescent, and Western blot analyses of their expression of epidermal (E-cadherin) and mesenchymal (vimentin) proteins. Results: Immunohistochemical analysis showed that the keloid tissues had more vimentin-positive cells in the epidermis than the normal tissues. When normal primary keratinocytes were cultured with proinflammatory cytokines, the cobblestone-shaped cells changed to a spindle shape and many vimentin-positive cells were detected. When immortalized HaCaT keratinocytes were cocultured in split-well plates with normal or keloid-derived fibroblasts, they also underwent EMT, as indicated by their greater vimentin expression on Western blot analysis compared with HaCaT cells that were cultured alone. Conclusions: EMT was observed in keloid specimens. EMT was induced by inflammatory cytokines and fibroblasts. EMT may be involved in keloid generation and/or aggravation and may have potential as a keloid treatment target. PMID:27975033

  15. Endothelial, epithelial, and fibroblast cells exhibit specific splicing programs independently of their tissue of origin

    PubMed Central

    Mallinjoud, Pierre; Villemin, Jean-Philippe; Mortada, Hussein; Polay Espinoza, Micaela; Desmet, François-Olivier; Samaan, Samaan; Chautard, Emilie; Tranchevent, Léon-Charles; Auboeuf, Didier

    2014-01-01

    Alternative splicing is the main mechanism of increasing the proteome diversity coded by a limited number of genes. It is well established that different tissues or organs express different splicing variants. However, organs are composed of common major cell types, including fibroblasts, epithelial, and endothelial cells. By analyzing large-scale data sets generated by The ENCODE Project Consortium and after extensive RT-PCR validation, we demonstrate that each of the three major cell types expresses a specific splicing program independently of its organ origin. Furthermore, by analyzing splicing factor expression across samples, publicly available splicing factor binding site data sets (CLIP-seq), and exon array data sets after splicing factor depletion, we identified several splicing factors, including ESRP1 and 2, MBNL1, NOVA1, PTBP1, and RBFOX2, that contribute to establishing these cell type–specific splicing programs. All of the analyzed data sets are freely available in a user-friendly web interface named FasterDB, which describes all known splicing variants of human and mouse genes and their splicing patterns across several dozens of normal and cancer cells as well as across tissues. Information regarding splicing factors that potentially contribute to individual exon regulation is also provided via a dedicated CLIP-seq and exon array data visualization interface. To the best of our knowledge, FasterDB is the first database integrating such a variety of large-scale data sets to enable functional genomics analyses at exon-level resolution. PMID:24307554

  16. Hepatocyte growth factor/scatter factor induces a variety of tissue- specific morphogenic programs in epithelial cells

    PubMed Central

    1995-01-01

    Hepatocyte growth factor/scatter factor (HGF/SF) is the mesenchymal ligand of the epithelial tyrosine kinase receptor c-Met. In vitro, HGF/SF has morphogenic properties, e.g., induces kidney epithelial cells to form branching ducts in collagen gels. Mutation of the HGF/SF gene in mice results in embryonic lethality due to severe liver and placenta defects. Here, we have evaluated the morphogenic activity of HGF/SF with a large variety of epithelial cells grown in three- dimensional collagen matrices. We found that HGF/SF induces SW 1222 colon carcinoma cells to form crypt-like structures. In these organoids, cells exhibit apical/basolateral polarity and build a well- developed brush border towards the lumen. Capan 2 pancreas carcinoma cells, upon addition of HGF/SF, develop large hollow spheroids lined with a tight layer of polarized cells. Collagen inside the cysts is digested and the cells show features of pancreatic ducts. HGF/SF induces EpH4 mammary epithelial cells to form long branches with end- buds that resemble developing mammary ducts. pRNS-1-1 prostate epithelial cells in the presence of HGF/SF develop long ducts with distal branching as found in the prostate. Finally, HGF/SF simulates alveolar differentiation in LX-1 lung carcinoma cells. Expression of transfected HGF/SF cDNA in LX-1 lung carcinoma and EpH4 mammary epithelial cells induce morphogenesis in an autocrine manner. In the cell lines tested, HGF/SF activated the Met receptor by phosphorylation of tyrosine residues. These data show that HGF/SF induces intrinsic, tissue-specific morphogenic activities in a wide variety of epithelial cells. Apparently, HGF/SF triggers respective endogenous programs and is thus an inductive, not an instructive, mesenchymal effector for epithelial morphogenesis. PMID:8522613

  17. Generation of lung epithelial-like tissue from human embryonic stem cells

    PubMed Central

    2009-01-01

    Background Human embryonic stem cells (hESC) have the capacity to differentiate in vivo and in vitro into cells from all three germ lineages. The aim of the present study was to investigate the effect of specific culture conditions on the differentiation of hESC into lung epithelial cells. Methods Undifferentiated hESC, grown on a porous membrane in hESC medium for four days, were switched to a differentiation medium for four days; this was followed by culture in air-liquid interface conditions during another 20 days. Expression of several lung markers was measured by immunohistochemistry and by quantitative real-time RT-PCR at four different time points throughout the differentiation and compared to appropriate controls. Results Expression of CC16 and NKX2.1 showed a 1,000- and 10,000- fold increase at day 10 of differentiation. Other lung markers such as SP-C and Aquaporin 5 had the highest expression after twenty days of culture, as well as two markers for ciliated cells, FOXJ1 and β-tubulin IV. The results from qRT-PCR were confirmed by immunohistochemistry on paraffin-embedded samples. Antibodies against CC16, SP-A and SP-C were chosen as specific markers for Clara Cells and alveolar type II cells. The functionality was tested by measuring the secretion of CC16 in the medium using an enzyme immunoassay. Conclusion These results suggest that by using our novel culture protocol hESC can be differentiated into the major cell types of lung epithelial tissue. PMID:19891764

  18. Dual Infection and Superinfection Inhibition of Epithelial Skin Cells by Two Alphaherpesviruses Co-Occur in the Natural Host

    PubMed Central

    Jarosinski, Keith W.

    2012-01-01

    Hosts can be infected with multiple herpesviruses, known as superinfection; however, superinfection of cells is rare due to the phenomenon known as superinfection inhibition. It is believed that dual infection of cells occurs in nature, based on studies examining genetic exchange between homologous alphaherpesviruses in the host, but to date, this has not been directly shown in a natural model. In this report, gallid herpesvirus 2 (GaHV-2), better known as Marek’s disease virus (MDV), was used in its natural host, the chicken, to determine whether two homologous alphaherpesviruses can infect the same cells in vivo. MDV shares close similarities with the human alphaherpesvirus, varicella zoster virus (VZV), with respect to replication in the skin and exit from the host. Recombinant MDVs were generated that express either the enhanced GFP (eGFP) or monomeric RFP (mRFP) fused to the UL47 (VP13/14) herpesvirus tegument protein. These viruses exhibited no alteration in pathogenic potential and expressed abundant UL47-eGFP or -mRFP in feather follicle epithelial cells in vivo. Using laser scanning confocal microscopy, it was evident that these two similar, but distinguishable, viruses were able to replicate within the same cells of their natural host. Evidence of superinfection inhibition was also observed. These results have important implications for two reasons. First, these results show that during natural infection, both dual infection of cells and superinfection inhibition can co-occur at the cellular level. Secondly, vaccination against MDV with homologous alphaherpesvirus like attenuated GaHV-2, or non-oncogenic GaHV-3 or meleagrid herpesvirus (MeHV-1) has driven the virus to greater virulence and these results implicate the potential for genetic exchange between homologous avian alphaherpesviruses that could drive increased virulence. Because the live attenuated varicella vaccine is currently being administered to children, who in turn could be superinfected

  19. Host Epithelial Cell Invasion by Campylobacter jejuni: Trigger or Zipper Mechanism?

    PubMed Central

    Ó Cróinín, Tadhg; Backert, Steffen

    2012-01-01

    Campylobacter jejuni, a spiral-shaped Gram-negative pathogen, is a highly frequent cause of gastrointestinal foodborne illness in humans worldwide. Clinical outcome of C. jejuni infections ranges from mild to severe diarrheal disease, and some other complications including reactive arthritis and Guillain–Barré syndrome. This review article highlights various C. jejuni pathogenicity factors, host cell determinants, and proposed signaling mechanisms involved in human host cell invasion and their potential role in the development of C. jejuni-mediated disease. A model is presented which outlines the various important interactions of C. jejuni with the intestinal epithelium, and we discuss the pro’s and con’s for the “zipper” over the “trigger” mechanism of invasion. Future work should clarify the contradictory role of some previously identified factors, and should identify and characterize novel virulence determinants, which are crucial to provide fresh insights into the diversity of strategies employed by this pathogen to cause disease. PMID:22919617

  20. Viruses exploit the tissue physiology of the host to spread in vivo.

    PubMed

    Sewald, Xaver; Motamedi, Nasim; Mothes, Walther

    2016-08-01

    Viruses are pathogens that strictly depend on their host for propagation. Over years of co-evolution viruses have become experts in exploiting the host cell biology and physiology to ensure efficient replication and spread. Here, we will first summarize the concepts that have emerged from in vitro cell culture studies to understand virus spread. We will then review the results from studies in living animals that reveal how viruses exploit the natural flow of body fluids, specific tissue architecture, and patterns of cell circulation and migration to spread within the host. Understanding tissue physiology will be critical for the design of antiviral strategies that prevent virus dissemination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Characterization of an apically derived epithelial membrane glycoprotein from bovine milk, which is expressed in capillary endothelia in diverse tissues

    PubMed Central

    1985-01-01

    A glycoprotein (PAS IV) of apparent Mr 76,000 was purified from bovine milk-fat-globule membrane and partially characterized. PAS IV contained mannose, galactose, and sialic acid as principal sugars (approximately 5.3% total carbohydrate [wt/wt]) and existed in milk in at least four isoelectric variants. The glycoprotein appeared to be an integral membrane protein by several criteria. PAS IV was recovered in the detergent phase of Triton X-114 extracts of milk-fat-globule membrane at room temperature. When bound to membrane, PAS IV was resistant to digestion by a number of proteinases, although after solubilization with non-ionic detergents, the protein was readily degraded. Amino acid analysis of the purified protein revealed a high percentage of amino acids with nonpolar residues. The location of PAS IV was determined in bovine tissues by using immunofluorescence techniques. In mammary tissue, PAS IV was located on both the apical surfaces of secretory epithelial cells and endothelial cells of capillaries. This glycoprotein was also detected in endothelial cells of heart, liver, spleen, pancreas, salivary gland, and small intestine. In addition to mammary epithelial cells, PAS IV was also located in certain other epithelial cells, most notably the bronchiolar epithelial cells of lung. The potential usefulness of this protein as a specific marker of capillary endothelial cells in certain tissues is discussed. PMID:3881456

  2. Haemophilus haemolyticus Interaction with Host Cells Is Different to Nontypeable Haemophilus influenzae and Prevents NTHi Association with Epithelial Cells

    PubMed Central

    Pickering, Janessa L.; Prosser, Amy; Corscadden, Karli J.; de Gier, Camilla; Richmond, Peter C.; Zhang, Guicheng; Thornton, Ruth B.; Kirkham, Lea-Ann S.

    2016-01-01

    Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen that resides in the upper respiratory tract and contributes to a significant burden of respiratory related diseases in children and adults. Haemophilus haemolyticus is a respiratory tract commensal that can be misidentified as NTHi due to high levels of genetic relatedness. There are reports of invasive disease from H. haemolyticus, which further blurs the species boundary with NTHi. To investigate differences in pathogenicity between these species, we optimized an in vitro epithelial cell model to compare the interaction of 10 H. haemolyticus strains with 4 NTHi and 4 H. influenzae-like haemophili. There was inter- and intra-species variability but overall, H. haemolyticus had reduced capacity to attach to and invade nasopharyngeal and bronchoalveolar epithelial cell lines (D562 and A549) within 3 h when compared with NTHi. H. haemolyticus was cytotoxic to both cell lines at 24 h, whereas NTHi was not. Nasopharyngeal epithelium challenged with some H. haemolyticus strains released high levels of inflammatory mediators IL-6 and IL-8, whereas NTHi did not elicit an inflammatory response despite higher levels of cell association and invasion. Furthermore, peripheral blood mononuclear cells stimulated with H. haemolyticus or NTHi released similar and high levels of IL-6, IL-8, IL-10, IL-1β, and TNFα when compared with unstimulated cells but only NTHi elicited an IFNγ response. Due to the relatedness of H. haemolyticus and NTHi, we hypothesized that H. haemolyticus may compete with NTHi for colonization of the respiratory tract. We observed that in vitro pre-treatment of epithelial cells with H. haemolyticus significantly reduced NTHi attachment, suggesting interference or competition between the two species is possible and warrants further investigation. In conclusion, H. haemolyticus interacts differently with host cells compared to NTHi, with different immunostimulatory and cytotoxic

  3. The development of a tissue-engineered tracheobronchial epithelial model using a bilayered collagen-hyaluronate scaffold.

    PubMed

    O'Leary, Cian; Cavanagh, Brenton; Unger, Ronald E; Kirkpatrick, C James; O'Dea, Shirley; O'Brien, Fergal J; Cryan, Sally-Ann

    2016-04-01

    Today, chronic respiratory disease is one of the leading causes of mortality globally. Epithelial dysfunction can play a central role in its pathophysiology. The development of physiologically-representative in vitro model systems using tissue-engineered constructs might improve our understanding of epithelial tissue and disease. This study sought to engineer a bilayered collagen-hyaluronate (CHyA-B) scaffold for the development of a physiologically-representative 3D in vitro tracheobronchial epithelial co-culture model. CHyA-B scaffolds were fabricated by integrating a thin film top-layer into a porous sub-layer with lyophilisation. The film layer firmly connected to the sub-layer with delamination occurring at stresses of 12-15 kPa. Crosslinked scaffolds had a compressive modulus of 1.9 kPa and mean pore diameters of 70 μm and 80 μm, depending on the freezing temperature. Histological analysis showed that the Calu-3 bronchial epithelial cell line attached and grew on CHyA-B with adoption of an epithelial monolayer on the film layer. Immunofluorescence and qRT-PCR studies demonstrated that the CHyA-B scaffolds facilitated Calu-3 cell differentiation, with enhanced mucin expression, increased ciliation and the formation of intercellular tight junctions. Co-culture of Calu-3 cells with Wi38 lung fibroblasts was achieved on the scaffold to create a submucosal tissue analogue of the upper respiratory tract, validating CHyA-B as a platform to support co-culture and cellular organisation reminiscent of in vivo tissue architecture. In summary, this study has demonstrated that CHyA-B is a promising tool for the development of novel 3D tracheobronchial co-culture in vitro models with the potential to unravel new pathways in drug discovery and drug delivery.

  4. Vascular endothelial growth factor polymorphisms and a synchronized examination of plasma and tissue expression in epithelial ovarian cancers.

    PubMed

    Bhaskari, J; Premalata, C S; Shilpa, V; Rahul, B; Pallavi, V R; Ramesh, G; Krishnamoorthy, Lakshmi

    2016-01-01

    In this study, we have analyzed six genetic polymorphisms of the VEGF-A gene and correlated the genetic data with plasma and tissue expression of VEGF-A in epithelial ovarian carcinomas. A total of 130 cases including 95 malignant carcinomas, 17 low malignant potential and 18 benign tumours were studied. rs699947, rs833061, rs1570360, rs2010963, rs1413711 and rs3025039 were studied by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Plasma levels of VEGF-A were estimated by enzyme-linked immunosorbent assay (ELISA) and tissue expression of VEGF-A by immunohistochemistry (IHC). Four polymorphisms of the above excluding rs699947 and rs3025039 showed significant association with malignancy, and we observed the presence of positive correlation between haplotype CCGGCC and increased expression of VEGF-A in both plasma and tissues which also correlated with poor prognosis and recurrence suggesting a probable increase in resistance to treatment in such carriers. Highly upregulated tissue expression of VEGF-A was seen in all epithelial ovarian carcinomas with intensity of expression increasing from benign to malignant cases. ELISA data from our study showed an increase in circulating levels of VEGF-A in malignancies. VEGF-A plasma levels can be employed as a biomarker for high-grade malignancy in epithelial ovarian cancers alongside tissue expression and CA-125 levels. This study is unique due to the fact that a simultaneous analysis of plasma and tissue expression has been demonstrated and is a first such study in epithelial ovarian cancers and representing the Indian population (South-east Asian) synchronized with genetic polymorphism data as well.

  5. Novel Bioceramic Urethral Bulking Agents Elicit Improved Host Tissue Responses in a Rat Model.

    PubMed

    Mann-Gow, Travis K; King, Benjamin J; El-Ghannam, Ahmed; Knabe-Ducheyne, Christine; Kida, Masatoshi; Dall, Ole M; Krhut, Jan; Zvara, Peter

    2016-01-01

    Objectives. To test the physical properties and host response to the bioceramic particles, silica-calcium phosphate (SCPC10) and Cristobalite, in a rat animal model and compare their biocompatibility to the current clinically utilized urethral bulking materials. Material and Methods. The novel bulking materials, SCPC10 and Cristobalite, were suspended in hyaluronic acid sodium salt and injected into the mid urethra of a rat. Additional animals were injected with bulking materials currently in clinical use. Physiological response was assessed using voiding trials, and host tissue response was evaluated using hard tissue histology and immunohistochemical analysis. Distant organs were evaluated for the presence of particles or their components. Results. Histological analysis of the urethral tissue five months after injection showed that both SCPC10 and Cristobalite induced a more robust fibroblastic and histiocytic reaction, promoting integration and encapsulation of the particle aggregates, leading to a larger bulking effect. Concentrations of Ca, Na, Si, and P ions in the experimental groups were comparable to control animals. Conclusions. This side-by-side examination of urethral bulking agents using a rat animal model and hard tissue histology techniques compared two newly developed bioactive ceramic particles to three of the currently used bulking agents. The local host tissue response and bulking effects of bioceramic particles were superior while also possessing a comparable safety profile.

  6. Novel Bioceramic Urethral Bulking Agents Elicit Improved Host Tissue Responses in a Rat Model

    PubMed Central

    Mann-Gow, Travis K.; King, Benjamin J.; El-Ghannam, Ahmed; Knabe-Ducheyne, Christine; Kida, Masatoshi; Dall, Ole M.; Krhut, Jan

    2016-01-01

    Objectives. To test the physical properties and host response to the bioceramic particles, silica-calcium phosphate (SCPC10) and Cristobalite, in a rat animal model and compare their biocompatibility to the current clinically utilized urethral bulking materials. Material and Methods. The novel bulking materials, SCPC10 and Cristobalite, were suspended in hyaluronic acid sodium salt and injected into the mid urethra of a rat. Additional animals were injected with bulking materials currently in clinical use. Physiological response was assessed using voiding trials, and host tissue response was evaluated using hard tissue histology and immunohistochemical analysis. Distant organs were evaluated for the presence of particles or their components. Results. Histological analysis of the urethral tissue five months after injection showed that both SCPC10 and Cristobalite induced a more robust fibroblastic and histiocytic reaction, promoting integration and encapsulation of the particle aggregates, leading to a larger bulking effect. Concentrations of Ca, Na, Si, and P ions in the experimental groups were comparable to control animals. Conclusions. This side-by-side examination of urethral bulking agents using a rat animal model and hard tissue histology techniques compared two newly developed bioactive ceramic particles to three of the currently used bulking agents. The local host tissue response and bulking effects of bioceramic particles were superior while also possessing a comparable safety profile. PMID:27688751

  7. Epithelial-stromal interaction via Notch signaling is essential for the full maturation of gut-associated lymphoid tissues.

    PubMed

    Obata, Yuuki; Kimura, Shunsuke; Nakato, Gaku; Iizuka, Keito; Miyagawa, Yurika; Nakamura, Yutaka; Furusawa, Yukihiro; Sugiyama, Machiko; Suzuki, Keiichiro; Ebisawa, Masashi; Fujimura, Yumiko; Yoshida, Hisahiro; Iwanaga, Toshihiko; Hase, Koji; Ohno, Hiroshi

    2014-12-01

    Intrinsic Notch signaling in intestinal epithelial cells restricts secretory cell differentiation. In gut-associated lymphoid tissue (GALT), stromal cells located beneath the follicle-associated epithelium (FAE) abundantly express the Notch ligand delta-like 1 (Dll1). Here, we show that mice lacking Rbpj-a gene encoding a transcription factor implicated in Notch signaling-in intestinal epithelial cells have defective GALT maturation. This defect can be attributed to the expansion of goblet cells, which leads to the down-regulation of CCL20 in FAE. These data demonstrate that epithelial Notch signaling maintained by stromal cells contributes to the full maturation of GALT by restricting secretory cell differentiation in FAE.

  8. Epithelial-Mesenchymal Interactions in Urinary Bladder and Small Intestine and How to Apply Them in Tissue Engineering.

    PubMed

    Jerman, Urška Dragin; Kreft, Mateja Erdani; Veranič, Peter

    2015-12-01

    Reciprocal interactions between the epithelium and mesenchyme are essential for the establishment of proper tissue morphology during organogenesis and tissue regeneration as well as for the maintenance of cell differentiation. With this review, we highlight the importance of epithelial-mesenchymal cross talk in healthy tissue and further discuss its significance in engineering functional tissues in vitro. We focus on the urinary bladder and small intestine, organs that are often compromised by disease and are as such in need of research that would advance effective treatment or tissue replacement. To date, the understanding of epithelial-mesenchymal reciprocal interactions has enabled the development of in vitro biomimetic tissue equivalents that have provided many possibilities in treating defective, damaged, or even cancerous tissues. Although research of the past several years has advanced the field of bladder and small intestine tissue engineering, one must be aware of its current limitations in successfully and above all safely introducing tissue-engineered constructs into clinical practice. Special attention is in particular needed when treating cancerous tissues, as initially successful tumor excision and tissue reconstruction may later on result in cancer recurrence due to oncogenic signals originating from an altered stroma. Recent rather poor outcomes in pioneering clinical trials of bladder reconstructions should serve as a reminder that recreating a functional organ to replace a dysfunctional one is an objective far more difficult to reach than initially foreseen. When considering effective tissue engineering approaches for diseased tissues in humans, it is imperative to introduce animal models with dysfunctional or, even more importantly, cancerous organs, which would greatly contribute to predicting possible complications and, hence, reducing risks when translating to the clinic.

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

    PubMed Central

    Su, Tin Tin

    2016-01-01

    Drosophila melanogaster larvae irradiated with doses of ionizing radiation (IR) that kill about half of the cells in larval imaginal discs still develop into viable adults. How surviving cells compensate for IR-induced cell death to produce organs of normal size and appearance remains an active area of investigation. We have identified a subpopulation of cells within the continuous epithelium of Drosophila larval wing discs that shows intrinsic resistance to IR- and drug-induced apoptosis. These cells reside in domains of high Wingless (Wg, Drosophila Wnt-1) and STAT92E (sole Drosophila signal transducer and activator of transcription [STAT] homolog) activity and would normally form the hinge in the adult fly. Resistance to IR-induced apoptosis requires STAT and Wg and is mediated by transcriptional repression of the pro-apoptotic gene reaper. Lineage tracing experiments show that, following irradiation, apoptosis-resistant cells lose their identity and translocate to areas of the wing disc that suffered abundant cell death. Our findings provide a new paradigm for regeneration in which it is unnecessary to invoke special damage-resistant cell types such as stem cells. Instead, differences in gene expression within a population of genetically identical epithelial cells can create a subpopulation with greater resistance, which, following damage, survive, alter their fate, and help regenerate the tissue. PMID:27584613

  10. Chemo-mechanical modeling of tumor growth in elastic epithelial tissue

    NASA Astrophysics Data System (ADS)

    Bratsun, Dmitry A.; Zakharov, Andrey P.; Pismen, Len

    2016-08-01

    We propose a multiscale chemo-mechanical model of the cancer tumor development in the epithelial tissue. The epithelium is represented by an elastic 2D array of polygonal cells with its own gene regulation dynamics. The model allows the simulation of the evolution of multiple cells interacting via the chemical signaling or mechanically induced strain. The algorithm includes the division and intercalation of cells as well as the transformation of normal cells into a cancerous state triggered by a local failure of the spatial synchronization of the cellular rhythms driven by transcription/translation processes. Both deterministic and stochastic descriptions of the system are given for chemical signaling. The transformation of cells means the modification of their respective parameters responsible for chemo-mechanical interactions. The simulations reproduce a distinct behavior of invasive and localized carcinoma. Generally, the model is designed in such a way that it can be readily modified to take account of any newly understood gene regulation processes and feedback mechanisms affecting chemo-mechanical properties of cells.

  11. Chemo-mechanical modeling of tumor growth in elastic epithelial tissue

    SciTech Connect

    Bratsun, Dmitry A.; Zakharov, Andrey P.; Pismen, Len

    2016-08-02

    We propose a multiscale chemo-mechanical model of the cancer tumor development in the epithelial tissue. The epithelium is represented by an elastic 2D array of polygonal cells with its own gene regulation dynamics. The model allows the simulation of the evolution of multiple cells interacting via the chemical signaling or mechanically induced strain. The algorithm includes the division and intercalation of cells as well as the transformation of normal cells into a cancerous state triggered by a local failure of the spatial synchronization of the cellular rhythms driven by transcription/translation processes. Both deterministic and stochastic descriptions of the system are given for chemical signaling. The transformation of cells means the modification of their respective parameters responsible for chemo-mechanical interactions. The simulations reproduce a distinct behavior of invasive and localized carcinoma. Generally, the model is designed in such a way that it can be readily modified to take account of any newly understood gene regulation processes and feedback mechanisms affecting chemo-mechanical properties of cells.

  12. Rap1 integrates tissue polarity, lumen formation, and tumorigenicpotential in human breast epithelial cells

    SciTech Connect

    Itoh, Masahiko; Nelson, Celeste M.; Myers, Connie A.; Bissell,Mina J.

    2006-09-29

    Maintenance of apico-basal polarity in normal breast epithelial acini requires a balance between cell proliferation, cell death, and proper cell-cell and cell-extracellular matrix signaling. Aberrations in any of these processes can disrupt tissue architecture and initiate tumor formation. Here we show that the small GTPase Rap1 is a crucial element in organizing acinar structure and inducing lumen formation. Rap1 activity in malignant HMT-3522 T4-2 cells is appreciably higher than in S1 cells, their non-malignant counterparts. Expression of dominant-negative Rap1 resulted in phenotypic reversion of T4-2 cells, led to formation of acinar structures with correct apico-basal polarity, and dramatically reduced tumor incidence despite the persistence of genomic abnormalities. The resulting acini contained prominent central lumina not observed when other reverting agents were used. Conversely, expression of dominant-active Rap1 in T4-2 cells inhibited phenotypic reversion and led to increased invasiveness and tumorigenicity. Thus, Rap1 acts as a central regulator of breast architecture, with normal levels of activation instructing apical polarity during acinar morphogenesis, and increased activation inducing tumor formation and progression to malignancy.

  13. KCC isoforms in a human lens epithelial cell line (B3) and lens tissue extracts.

    PubMed

    Misri, Sandeep; Chimote, Ameet A; Adragna, Norma C; Warwar, Ronald; Brown, Thomas L; Lauf, Peter K

    2006-11-01

    We recently reported potassium-chloride cotransporter activity in human lens epithelial B3 (HLE-B3) cells. The purpose of the present study was to demonstrate in these cells as well as in human lens tissue the potassium-chloride cotransport (KCC) isoforms by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and immunofluorescence microscopy. Of the four KCC genes known to encode the respective proteins and their spliced variants, RT-PCR with both rat and human primers revealed the predicted cDNA fragments of KCC1, KCC3a, KCC3b, and KCC4 but not KCC2 in both HLE-B3 cells and in human lens tissue extracts from cataractous patients. Polyclonal rabbit (rb) anti-rat (rt) and anti-human (hm) antibodies against rtKCC1 and hmKCC3, respectively, and a commercially available rb-anti-mouse (ms) KCC4 antibody were used. Rb anti-rtKCC1-ECL3 [against epitopes within the large extracellular loop 3 (ECL3)] revealed a 150kDa band in HLE-B3 cells consistent with the known molecular weight of KCC1. Rb anti-hmKCC3-ECL3 yielded three bands of 150, 122 and 105kDa, evidence for the presence of KCC3a, KCC3b and possibly KCC3c isoforms. The 122 and 112kDa bands were also demonstrated by rb anti-hmKCC3-CTD [the C-terminal domain (CTD)]. Rb anti-msKCC4 antibody only showed a 100kDa band in HLE-B3 cells. In the human lens tissues, a 115kDa protein was detected with rb anti-rtKCC1-ECL3 and a 100kDa band with rb anti-msKCC4, however, no bands with rb anti-hmKCC3-ECL3 or rb anti-hmKCC3-CTD. Fluorescence microscopy revealed immunocytochemical cytoplasmic and membrane labeling of HLE-B3 cells with anti-KCC1, -KCC3 (laser confocal microscopy) and -KCC4 antibodies and a Cy3-tagged secondary antibody. Hence HLE-B3 cells expressed proteins of the KCC1, KCC3a, b, and KCC4 isoforms, whereas surgically removed cataractous lens tissue expressed only those of KCC1 and KCC4.

  14. The influence of surface topography of a porous perfluoropolyether polymer on corneal epithelial tissue growth and adhesion.

    PubMed

    Evans, Margaret D M; Chaouk, Hassan; Wilkie, John S; Dalton, Beatrice A; Taylor, Sarah; Xie, Ruo Zhong; Hughes, Timothy C; Johnson, Graham; McFarland, Gail A; Griesser, Hans H; Steele, John G; Meijs, Gordon F; Sweeney, Deborah F; McLean, Keith M

    2011-12-01

    Design principles for corneal implants are challenging and include permeability which inherently involves pore openings on the polymer surface. These topographical cues can be significant to a successful clinical outcome where a stratified epithelium is needed over the device surface, such as with a corneal onlay or corneal repair material. The impact of polymer surface topography on the growth and adhesion of corneal epithelial tissue was assessed using porous perfluoropolyether membranes with a range of surface topography. Surfaces were characterised by AFM and XPS, and the permeability and water content of membranes was measured. Biological testing of membranes involved a 21-day in vitro tissue assay to evaluate migration, stratification and adhesion of corneal epithelium. Similar parameters were monitored in vivo by surgically implanting membranes into feline corneas for up to 5 months. Data showed optimal growth and adhesion of epithelial tissue in vitro when polymer surface features were below a 150 nm RMS value. Normal processes of tissue growth and adhesion were disrupted when RMS values approached 300 nm. Data from the in vivo study confirmed these findings. Together, outcomes demonstrated the importance of surface topography in the design of implantable devices that depend on functional epithelial cover.

  15. Looking Beyond the Genes: The Interplay Between Signaling Pathways and Mechanics in the Shaping and Diversification of Epithelial Tissues.

    PubMed

    Urdy, S; Goudemand, N; Pantalacci, S

    2016-01-01

    The core of Evo-Devo lies in the intuition that the way tissues grow during embryonic development, the way they sustain their structure and function throughout lifetime, and the way they evolve are closely linked. Epithelial tissues are ubiquitous in metazoans, covering the gut and internal branched organs, as well as the skin and its derivatives (ie, teeth). Here, we discuss in vitro, in vivo, and in silico studies on epithelial tissues to illustrate the conserved, dynamical, and complex aspects of their development. We then explore the implications of the dynamical and nonlinear nature of development on the evolution of their size and shape at the phenotypic and genetic levels. In rare cases, when the interplay between signaling and mechanics is well understood at the cell level, it is becoming clear that the structure of development leads to covariation of characters, an integration which in turn provides some predictable structure to evolutionary changes. We suggest that such nonlinear systems are prone to genetic drift, cryptic genetic variation, and context-dependent mutational effects. We argue that experimental and theoretical studies at the cell level are critical to our understanding of the phenotypic and genetic evolution of epithelial tissues, including carcinomas.

  16. Concise review: can the intrinsic power of branching morphogenesis be used for engineering epithelial tissues and organs?

    PubMed

    Nigam, Sanjay K

    2013-12-01

    Branching morphogenesis is critical to the development of organs such as kidney, lung, mammary gland, prostate, pancreas, and salivary gland. Essentially, an epithelial bud becomes an iterative tip-stalk generator (ITSG) able to form a tree of branching ducts and/or tubules. In different organs, branching morphogenesis is governed by similar sets of genes. Epithelial branching has been recapitulated in vitro (or ex vivo) using three-dimensional cell culture and partial organ culture systems, and several such systems relevant to kidney tissue engineering are discussed here. By adapting systems like these it may be possible to harness the power inherent in the ITSG program to propagate and engineer epithelial tissues and organs. It is also possible to conceive of a universal ITSG capable of propagation that may, by recombination with organ-specific mesenchymal cells, be used for engineering many organ-like tissues similar to the organ from which the mesenchyme cells were derived, or toward which they are differentiated (from stem cells). The three-dimensional (3D) branched epithelial structure could act as a dynamic branching cellular scaffold to establish the architecture for the rest of the tissue. Another strategy-that of recombining propagated organ-specific ITSGs in 3D culture with undifferentiated mesenchymal stem cells-is also worth exploring. If feasible, such engineered tissues may be useful for the ex vivo study of drug toxicity, developmental biology, and physiology in the laboratory. Over the long term, they have potential clinical applications in the general fields of transplantation, regenerative medicine, and bioartificial medical devices to aid in the treatment of chronic kidney disease, diabetes, and other diseases.

  17. Real-Time Sensing of Enteropathogenic E. coli-Induced Effects on Epithelial Host Cell Height, Cell-Substrate Interactions, and Endocytic Processes by Infrared Surface Plasmon Spectroscopy

    PubMed Central

    Zlotkin-Rivkin, Efrat; Rund, David; Melamed-Book, Naomi; Zahavi, Eitan Erez; Perlson, Eran; Mercone, Silvana; Golosovsky, Michael; Davidov, Dan; Aroeti, Benjamin

    2013-01-01

    Enteropathogenic Escherichia coli (EPEC) is an important, generally non-invasive, bacterial pathogen that causes diarrhea in humans. The microbe infects mainly the enterocytes of the small intestine. Here we have applied our newly developed infrared surface plasmon resonance (IR-SPR) spectroscopy approach to study how EPEC infection affects epithelial host cells. The IR-SPR experiments showed that EPEC infection results in a robust reduction in the refractive index of the infected cells. Assisted by confocal and total internal reflection microscopy, we discovered that the microbe dilates the intercellular gaps and induces the appearance of fluid-phase-filled pinocytic vesicles in the lower basolateral regions of the host epithelial cells. Partial cell detachment from the underlying substratum was also observed. Finally, the waveguide mode observed by our IR-SPR analyses showed that EPEC infection decreases the host cell's height to some extent. Together, these observations reveal novel impacts of the pathogen on the host cell architecture and endocytic functions. We suggest that these changes may induce the infiltration of a watery environment into the host cell, and potentially lead to failure of the epithelium barrier functions. Our findings also indicate the great potential of the label-free IR-SPR approach to study the dynamics of host-pathogen interactions with high spatiotemporal sensitivity. PMID:24194932

  18. Halide peroxidase in tissues that interact with bacteria in the host squid Euprymna scolopes.

    PubMed

    Small, A L; McFall-Ngai, M J

    1999-03-15

    An enzyme with similarities to myeloperoxidase, the antimicrobial halide peroxidase in mammalian neutrophils, occurs abundantly in the light organ tissue of Euprymna scolopes, a squid that maintains a beneficial association with the luminous bacterium Vibrio fischeri. Using three independent assays typically applied to the analysis of halide peroxidase enzymes, we directly compared the activity of the squid enzyme with that of human myeloperoxidase. One of these methods, the diethanolamine assay, confirmed that the squid peroxidase requires halide ions for its activity. The identification of a halide peroxidase in a cooperative bacterial association suggested that this type of enzyme can function not only to control pathogens, but also to modulate the interactions of host animals with their beneficial partners. To determine whether the squid peroxidase functions under both circumstances, we examined its distribution in a variety of host tissues, including those that typically interact with bacteria and those that do not. Tissues interacting with bacteria included those that have specific cooperative associations with bacteria (i.e., the light organ and accessory nidamental gland) and those that have transient nonspecific interactions with bacteria (i.e., the gills, which clear the cephalopod circulatory system of invading microorganisms). These bacteria-associated tissues were compared with the eye, digestive gland, white body, and ink-producing tissues, which do not typically interact directly with bacteria. Peroxidase enzyme assays, immunocytochemical localization, and DNA-RNA hybridizations showed that the halide-dependent peroxidase is consistently expressed in high concentration in tissues that interact bacteria. Elevated levels of the peroxidase were also found in the ink-producing tissues, which are known to have enzymatic pathways associated with antimicrobial activity. Taken together, these data suggest that the host uses a common biochemical response to

  19. Host immune and apoptotic responses to avian influenza virus H9N2 in human tracheobronchial epithelial cells.

    PubMed

    Xing, Zheng; Harper, Richart; Anunciacion, Jerome; Yang, Zengqi; Gao, Wei; Qu, Bingqian; Guan, Yi; Cardona, Carol J

    2011-01-01

    The avian influenza virus H9N2 subtype has circulated in wild birds, is prevalent in domestic poultry, and has successfully crossed the species boundary to infect humans. Phylogenetic analyses showed that viruses of this subtype appear to have contributed to the generation of highly pathogenic H5N1 viruses. Little is known about the host responses to H9N2 viruses in human airway respiratory epithelium, the primary portal for viral infection. Using an apically differentiated primary human tracheobronchial epithelial (TBE) culture, we examined host immune responses to infection by an avian H9N2 virus, in comparison with a human H9N2 isolate. We found that IFN-β was the prominent antiviral component, whereas interferon gamma-induced protein 10 kDa (IP-10), chemokine (C-C motif) ligand (CCL)-5 and TNF-α may be critical in proinflammatory responses to H9N2 viruses. In contrast, proinflammatory IL-1β, IL-8, and even IL-6 may only play a minor role in pathogenicity. Apparently Toll-like receptor (TLR)-3, TLR-7, and melanoma differentiation-associated gene 5 (MDA-5) contributed to the innate immunity against the H9N2 viruses, and MDA-5 was important in the induction of IFN-β. We showed that the avian H9N2 virus induced apoptosis through the mitochondria/cytochrome c-mediated intrinsic pathway, in addition to the caspase 8-mediated extrinsic pathway, as evidenced by the cytosolic presence of active caspase 9 and cytochrome c, independent of truncated BH3 interacting domain death agonist (Bid) activation. Further, we demonstrated that FLICE-like inhibitory protein (FLIP), an apoptotic dual regulator, and the p53-dependent Bcl-2 family members, Bax and Bcl-x(s), appeared to be involved in the regulation of extrinsic and intrinsic apoptotic pathways, respectively. The findings in this study will further our understanding of host defense mechanisms and the pathogenesis of H9N2 influenza viruses in human respiratory epithelium.

  20. Epithelial cell volume regulation in hypotonic fluids: studies using a model tissue culture renal epithelial cell system.

    PubMed

    Simmons, N L

    1984-01-01

    The cultured renal epithelial cell line MDCK has been used in a study of cell volume regulation, emphasis being placed upon cell swelling in hypotonic media. MDCK cell volume was measured directly by electronic cell sizing using a Coulter counter in MDCK cell suspensions; this method gave comparable values for cell water when compared with those obtained using an intracellular space marker [14C]3-O-methyl glucose. MDCK cells behaved as perfect osmometers when suspended in hypertonic fluid (cell shrinkage). Cellular swelling in hypotonic media, in certain conditions, was found to be less than expected for an ideal osmometer. Non-ideal swelling was found to be the result of a substantial loss of intracellular K+ (Cl-) due to a specific increase in membrane K+ permeability. The membrane channel mediating the increased net K+ loss was separate, by pharmacological identity, from the Na+-K+ pump, the diuretic-sensitive co-transport system and a Gardos-type channel inhibited by quinine. A role for increased Ca2+ influx mediating the increased K+ permeability is suggested by results from hypotonic exposure in nominally Ca2+-free solutions.

  1. Two New Complete Genome Sequences Offer Insight into Host and Tissue Specificity of Plant Pathogenic Xanthomonas spp.▿†

    PubMed Central

    Bogdanove, Adam J.; Koebnik, Ralf; Lu, Hong; Furutani, Ayako; Angiuoli, Samuel V.; Patil, Prabhu B.; Van Sluys, Marie-Anne; Ryan, Robert P.; Meyer, Damien F.; Han, Sang-Wook; Aparna, Gudlur; Rajaram, Misha; Delcher, Arthur L.; Phillippy, Adam M.; Puiu, Daniela; Schatz, Michael C.; Shumway, Martin; Sommer, Daniel D.; Trapnell, Cole; Benahmed, Faiza; Dimitrov, George; Madupu, Ramana; Radune, Diana; Sullivan, Steven; Jha, Gopaljee; Ishihara, Hiromichi; Lee, Sang-Won; Pandey, Alok; Sharma, Vikas; Sriariyanun, Malinee; Szurek, Boris; Vera-Cruz, Casiana M.; Dorman, Karin S.; Ronald, Pamela C.; Verdier, Valérie; Dow, J. Maxwell; Sonti, Ramesh V.; Tsuge, Seiji; Brendel, Volker P.; Rabinowicz, Pablo D.; Leach, Jan E.; White, Frank F.; Salzberg, Steven L.

    2011-01-01

    Xanthomonas is a large genus of bacteria that collectively cause disease on more than 300 plant species. The broad host range of the genus contrasts with stringent host and tissue specificity for individual species and pathovars. Whole-genome sequences of Xanthomonas campestris pv. raphani strain 756C and X. oryzae pv. oryzicola strain BLS256, pathogens that infect the mesophyll tissue of the leading models for plant biology, Arabidopsis thaliana and rice, respectively, were determined and provided insight into the genetic determinants of host and tissue specificity. Comparisons were made with genomes of closely related strains that infect the vascular tissue of the same hosts and across a larger collection of complete Xanthomonas genomes. The results suggest a model in which complex sets of adaptations at the level of gene content account for host specificity and subtler adaptations at the level of amino acid or noncoding regulatory nucleotide sequence determine tissue specificity. PMID:21784931

  2. Two new complete genome sequences offer insight into host and tissue specificity of plant pathogenic Xanthomonas spp.

    PubMed

    Bogdanove, Adam J; Koebnik, Ralf; Lu, Hong; Furutani, Ayako; Angiuoli, Samuel V; Patil, Prabhu B; Van Sluys, Marie-Anne; Ryan, Robert P; Meyer, Damien F; Han, Sang-Wook; Aparna, Gudlur; Rajaram, Misha; Delcher, Arthur L; Phillippy, Adam M; Puiu, Daniela; Schatz, Michael C; Shumway, Martin; Sommer, Daniel D; Trapnell, Cole; Benahmed, Faiza; Dimitrov, George; Madupu, Ramana; Radune, Diana; Sullivan, Steven; Jha, Gopaljee; Ishihara, Hiromichi; Lee, Sang-Won; Pandey, Alok; Sharma, Vikas; Sriariyanun, Malinee; Szurek, Boris; Vera-Cruz, Casiana M; Dorman, Karin S; Ronald, Pamela C; Verdier, Valérie; Dow, J Maxwell; Sonti, Ramesh V; Tsuge, Seiji; Brendel, Volker P; Rabinowicz, Pablo D; Leach, Jan E; White, Frank F; Salzberg, Steven L

    2011-10-01

    Xanthomonas is a large genus of bacteria that collectively cause disease on more than 300 plant species. The broad host range of the genus contrasts with stringent host and tissue specificity for individual species and pathovars. Whole-genome sequences of Xanthomonas campestris pv. raphani strain 756C and X. oryzae pv. oryzicola strain BLS256, pathogens that infect the mesophyll tissue of the leading models for plant biology, Arabidopsis thaliana and rice, respectively, were determined and provided insight into the genetic determinants of host and tissue specificity. Comparisons were made with genomes of closely related strains that infect the vascular tissue of the same hosts and across a larger collection of complete Xanthomonas genomes. The results suggest a model in which complex sets of adaptations at the level of gene content account for host specificity and subtler adaptations at the level of amino acid or noncoding regulatory nucleotide sequence determine tissue specificity.

  3. Comparative study of the cytoplasmic organelles of epithelial cell lines derived from human carcinomas and nonmalignant tissues

    SciTech Connect

    Springer, E.L.

    1980-03-01

    The cytoplasmic organelles of 16 human epithelial cell lines have been characterized by electron microscopy. The cell lines were derived from normal, nonmalignant tissues of cancerous organs and from primary and metastatic carcinomas. Mitochondrial pleomorphism was expressed slightly by normal, to variable degrees by lines derived from nonmalignant tissues of cancerous organs, and to a much greater extent by all lines derived from malignant tissues. Hypertrophied mitochondria and longitudinal cristal arrangement were found in almost all the malignant lines, but not in any lines derived from nonmalignant tissues of cancerous organs or from normal tissues. All the lines appeared differentiate and showed slightly to moderately developed Golgi and smooth and rough endoplasmic reticula. There were no significant ultrastructural differences in cells at different passage levels or subconfluent and confluent tumor cells; however, more tight junctions were observed in confluent than in subconfluent normal cells.

  4. Epithelial-mesenchymal transition in keloid tissues and TGF-β1-induced hair follicle outer root sheath keratinocytes.

    PubMed

    Yan, Li; Cao, Rui; Wang, Lianzhao; Liu, Yuanbo; Pan, Bo; Yin, Yanhua; Lv, Xiaoyan; Zhuang, Qiang; Sun, Xuejian; Xiao, Ran

    2015-01-01

    Keloid is a skin fibrotic disease with the characteristics of recurrence and invasion, its pathogenesis still remains unrevealed. The epithelial-mesenchymal transition (EMT) is critical for wound healing, fibrosis, recurrence, and invasion of cancer. We sought to investigate the EMT in keloid and the mechanism through which the EMT regulates keloid formation. In keloid tissues, the expressions of EMT-associated markers and transforming growth factor (TGF)-β1/Smad3 signaling were examined by immunohistochemistry. In the keloid epidermis and dermal tissue, the expressions of genes related to the regulation of skin homeostasis, fibroblast growth factor receptor 2 (FGFR2) and p63, were analyzed using quantitative real-time polymerase chain reaction. The results showed that accompanying the loss of the epithelial marker E-cadherin and the gain of the mesenchymal markers fibroblast-specific protein 1 (FSP1) and vimentin in epithelial cells from epidermis and skin appendages, and in endothelial cells from dermal microvessels, enhanced TGF-β1 expression and Smad3 phosphorylation were noted in keloid tissues. Moreover, alternative splicing of the FGFR2 gene switched the predominantly expressed isoform from FGFR2-IIIb to -IIIc, concomitant with the decreased expression of ΔNp63 and TAp63, which changes might partially account for abnormal epidermis and appendages in keloids. In addition, we found that TGF-β1-induced hair follicle outer root sheath keratinocytes (ORSKs) and normal skin epithelial cells underwent EMT in vitro with ORSKs exhibiting more obvious EMT changes and more similar expression profiles for EMT-associated and skin homeostasis-related genes as in keloid tissues, suggesting that ORSKs might play crucial roles in the EMT in keloids. Our study provided insights into the molecular mechanisms mediating the EMT pathogenesis of keloids.

  5. Effect of Endophytic Fusarium oxysporum on Host Preference of Radopholus similis to Tissue Culture Banana Plants.

    PubMed

    Athman, Shahasi Y; Dubois, Thomas; Coyne, Daniel; Gold, Clifford S; Labuschagne, Nico; Viljoen, Altus

    2006-12-01

    The burrowing nematode Radopholus similis is one of the major constraints to banana (Musa spp.) production worldwide. Resource-poor farmers can potentially manage R. similis by using naturally occurring banana endophytes, such as nonpathogenic Fusarium oxysporum, that are inoculated into tissue culture banana plantlets. At present, it is unclear at what stage in the R. similis infection process the endophytes are most effective. In this study, the effect of three endophytic F. oxysporum isolates (V5w2, Eny1.31i and Eny7.11o) on R. similis host preference of either endophyte-treated or untreated banana plants was investigated. No differences were observed between the proportion of nematodes attracted to either root segments excised from endophyte-treated or untreated plants, or in experiments using endophyte-treated and untreated tissue culture banana plantlets. These results imply that the early processes of banana plant host recognition by R. similis are not affected by endophyte infection.

  6. Regulation of alveolar procoagulant activity and permeability in direct acute lung injury by lung epithelial tissue factor.

    PubMed

    Shaver, Ciara M; Grove, Brandon S; Putz, Nathan D; Clune, Jennifer K; Lawson, William E; Carnahan, Robert H; Mackman, Nigel; Ware, Lorraine B; Bastarache, Julie A

    2015-11-01

    Tissue factor (TF) initiates the extrinsic coagulation cascade in response to tissue injury, leading to local fibrin deposition. Low levels of TF in mice are associated with increased severity of acute lung injury (ALI) after intratracheal LPS administration. However, the cellular sources of the TF required for protection from LPS-induced ALI remain unknown. In the current study, transgenic mice with cell-specific deletions of TF in the lung epithelium or myeloid cells were treated with intratracheal LPS to determine the cellular sources of TF important in direct ALI. Cell-specific deletion of TF in the lung epithelium reduced total lung TF expression to 39% of wild-type (WT) levels at baseline and to 29% of WT levels after intratracheal LPS. In contrast, there was no reduction of TF with myeloid cell TF deletion. Mice lacking myeloid cell TF did not differ from WT mice in coagulation, inflammation, permeability, or hemorrhage. However, mice lacking lung epithelial TF had increased tissue injury, impaired activation of coagulation in the airspace, disrupted alveolar permeability, and increased alveolar hemorrhage after intratracheal LPS. Deletion of epithelial TF did not affect alveolar permeability in an indirect model of ALI caused by systemic LPS infusion. These studies demonstrate that the lung epithelium is the primary source of TF in the lung, contributing 60-70% of total lung TF, and that lung epithelial, but not myeloid, TF may be protective in direct ALI.

  7. Transgenic tissue-type plasminogen activator expression improves host defense during Klebsiella pneumonia.

    PubMed

    Renckens, R; Roelofs, J J T H; Stegenga, M E; Florquin, S; Levi, M; Carmeliet, P; Van't Veer, C; van der Poll, T

    2008-04-01

    Severe pneumonia is associated with a local inhibition of fibrinolysis in the lung as reflected by strongly reduced pulmonary plasminogen activator activity. To study the effect of elevation of local plasminogen activator activity during pneumonia caused by the common respiratory pathogen Klebsiella pneumoniae. Female C57Bl/6 mice were inoculated intranasally with a replication-defective adenoviral vector expressing human tissue-type plasminogen activator or a control vector 24 h before intranasal infection with K. pneumoniae. Mice infected with Klebsiella via the airways developed overt pneumonia, which was accompanied by a downregulation of pulmonary tissue-type plasminogen activator levels at protein and mRNA levels. Pulmonary overexpression of human tissue-type plasminogen activator resulted in increased fibrinolytic activity in the lungs during pneumonia, as indicated by higher D-dimer levels and reduced fibrin deposition. Interestingly, overexpression of tissue-type plasminogen activator markedly improved host defense against pneumonia: mice treated with the tissue-type plasminogen activator vector displayed less bacterial growth and dissemination, attenuated distant organ injury and a reduced mortality. These data demonstrate that local elevation of plasminogen activator activity in the lungs improves host defense against severe gram-negative pneumonia and sepsis.

  8. Breast epithelial tissue morphology is affected in 3D cultures by species-specific collagen-based extracellular matrix.

    PubMed

    Dhimolea, Eugen; Soto, Ana M; Sonnenschein, Carlos

    2012-11-01

    Collagen-based gels have been widely used to determine the factors that regulate branching morphogenesis in the mammary gland. The patterns of biomechanical gradients and collagen reorganization influence the shape and orientation of epithelial structures in three-dimensional (3D) conditions. We explored in greater detail whether collagen type I fibers with distinct biomechanical and fiber-assembling properties, isolated from either bovine or rat tail tendon, differentially affected the epithelial phenotype in a tissue culture model of the human breast. Rat tail collagen fibers were densely packed into significantly longer and thicker bundles compared to those of the bovine type (average fascicle length 7.35 and 2.29 μm, respectively; p = 0.0001), indicating increased fiber alignment and biomechanical enablement in the former. MCF10A epithelial cells formed elaborated branched tubular structures in bovine but only nonbranched ducts and acini in rat tail collagen matrices. Ductal branching in bovine collagen was associated with interactions between neighboring structures mediated through packed collagen fibers; these fiber-mediated interactions were absent in rat tail collagen gels. Normal breast fibroblasts increased the final size and number of ducts only in rat tail collagen gels while not affecting branching. Our results suggest that the species of origin of collagen used in organotypic cultures may influence epithelial differentiation into alveolar or ductal structures and the patterns of epithelial branching. These observations underscore the importance of considering the species of origin and fiber alignment properties of collagen when engineering branching organs in 3D matrices and interpreting their role in the tissue phenotype.

  9. Candida albicans-epithelial interactions: dissecting the roles of active penetration, induced endocytosis and host factors on the infection process.

    PubMed

    Wächtler, Betty; Citiulo, Francesco; Jablonowski, Nadja; Förster, Stephanie; Dalle, Frederic; Schaller, Martin; Wilson, Duncan; Hube, Bernhard

    2012-01-01

    Candida albicans frequently causes superficial infections by invading and damaging epithelial cells, but may also cause systemic infections by penetrating through epithelial barriers. C. albicans is a remarkable pathogen because it can invade epithelial cells via two distinct mechanisms: induced endocytosis, analogous to facultative intracellular enteropathogenic bacteria, and active penetration, similar to plant pathogenic fungi. Here we investigated the contributions of the two invasion routes of C. albicans to epithelial invasion. Using selective cellular inhibition approaches and differential fluorescence microscopy, we demonstrate that induced endocytosis contributes considerably to the early time points of invasion, while active penetration represents the dominant epithelial invasion route. Although induced endocytosis depends mainly on Als3-E-cadherin interactions, we observed E-cadherin independent induced endocytosis. Finally, we provide evidence of a protective role for serum factors in oral infection: human serum strongly inhibited C. albicans adhesion to, invasion and damage of oral epithelial cells.

  10. Dendroctonus armandi (Curculionidae: Scolytinae) cytochrome P450s display tissue specificity and responses to host terpenoids.

    PubMed

    Dai, Lulu; Ma, Mingyuan; Gao, Guanqun; Chen, Hui

    2016-11-01

    Bark beetles oxidize the defensive allelochemicals of their host trees both to detoxify them and convert them into components of their pheromone systems which were catalyzed by cytochrome P450 enzymes (CYPs) and occur in different tissues of the insect. We study P450 genes in the Chinese white pine beetle (Dendroctonus armandi), and some bio-information analysis was done for the full-length deduced amino acid sequences. The tissue specificity of these P450 genes was determined in three tissues (antenna, gut and reproductive organs). Differential expression of the P450 genes was observed between sexes, and within these significant differences exposed to stimuli (α-pinene (1:1 racemic mix), (S)-(-)-α-pinene, (S)-(-)-β-pinene, (+)-3-carene, (±)-limonene and turpentine oil) at 24h. Increased expression of P450 genes suggested that they play a role in the detoxification of monoterpenes released by the host trees. The different transcript accumulation patterns of these bark beetle P450 genes provided insight into ecological interactions of D. armandi with its host pine.

  11. Myeloperoxidase targets oxidative host attacks to Salmonella and prevents collateral tissue damage.

    PubMed

    Schürmann, Nura; Forrer, Pascal; Casse, Olivier; Li, Jiagui; Felmy, Boas; Burgener, Anne-Valérie; Ehrenfeuchter, Nikolaus; Hardt, Wolf-Dietrich; Recher, Mike; Hess, Christoph; Tschan-Plessl, Astrid; Khanna, Nina; Bumann, Dirk

    2017-01-23

    Host control of infections crucially depends on the capability to kill pathogens with reactive oxygen species (ROS). However, these toxic molecules can also readily damage host components and cause severe immunopathology. Here, we show that neutrophils use their most abundant granule protein, myeloperoxidase, to target ROS specifically to pathogens while minimizing collateral tissue damage. A computational model predicted that myeloperoxidase efficiently scavenges diffusible H2O2 at the surface of phagosomal Salmonella and converts it into highly reactive HOCl (bleach), which rapidly damages biomolecules within a radius of less than 0.1 μm. Myeloperoxidase-deficient neutrophils were predicted to accumulate large quantities of H2O2 that still effectively kill Salmonella, but most H2O2 would leak from the phagosome. Salmonella stimulation of neutrophils from normal and myeloperoxidase-deficient human donors experimentally confirmed an inverse relationship between myeloperoxidase activity and extracellular H2O2 release. Myeloperoxidase-deficient mice infected with Salmonella had elevated hydrogen peroxide tissue levels and exacerbated oxidative damage of host lipids and DNA, despite almost normal Salmonella control. These data show that myeloperoxidase has a major function in mitigating collateral tissue damage during antimicrobial oxidative bursts, by converting diffusible long-lived H2O2 into highly reactive, microbicidal and locally confined HOCl at pathogen surfaces.

  12. Effect of energy intake on the metabolism of glucose and glutamine in rumen epithelial tissue

    SciTech Connect

    Harmon, D.L.

    1986-03-01

    Ten Holstein steers (579 kg average body weight) were fed either alfalfa hay (12.2% crude protein) or a 90% concentrate diet to supply 14.2 or 25.2 Mcal ME respectively for a minimum of 28 days. Samples of rumen epithelial tissue were removed at slaughter from the anterior ventral sac, washed free of feed particles and transported to the laboratory in oxygenated Krebs-Ringer bicarbonate buffer (KRB; pH 7.4). Papillae were weighed (100-200 mg) in triplicate into flasks containing 3 ml KRB with 1 mM glutamine or 5 mM glucose and acetate (50 mM), propionate (25 mM), butyrate (15 mM), lactate (1 mM) and glucose (5 mM) or glutamine (1 mM) as competing substrates. A parallel set of flasks contained 1 or .5 ..mu..Ci of (U-/sup 14/C)-glutamine or glucose respectively for /sup 14/CO/sub 2/ production. There were no interactions with dietary energy intake and substrate addition. Increasing the dietary energy intake increased (P < .01) rates of uptake, /sup 14/CO/sub 2/ production and net lactate production from glucose and increased the /sup 14/CO/sub 2/ production from glutamine. Addition of acetate, propionate, butyrate and lactate decreased (P < .05) uptake of glucose, but only propionate decreased /sup 14/CO/sub 2/ production from glucose (40%). Addition of butyrate and glucose decreased /sup 14/CO/sub 2/ production from glutamine while propionate addition decreased net glutamate production and increased net alanine production. At these substrate concentrations rates of glucose oxidation to /sup 14/CO/sub 2/ were 7-fold higher than glutamine.

  13. Lack of cyclin-dependent kinase 4 inhibits c-myc tumorigenic activities in epithelial tissues.

    PubMed

    Miliani de Marval, Paula L; Macias, Everardo; Rounbehler, Robert; Sicinski, Piotr; Kiyokawa, Hiroaki; Johnson, David G; Conti, Claudio J; Rodriguez-Puebla, Marcelo L

    2004-09-01

    The proto-oncogene c-myc encodes a transcription factor that is implicated in the regulation of cellular proliferation, differentiation, and apoptosis and that has also been found to be deregulated in several forms of human and experimental tumors. We have shown that forced expression of c-myc in epithelial tissues of transgenic mice (K5-Myc) resulted in keratinocyte hyperproliferation and the development of spontaneous tumors in the skin and oral cavity. Although a number of genes involved in cancer development are regulated by c-myc, the actual mechanisms leading to Myc-induced neoplasia are not known. Among the genes regulated by Myc is the cyclin-dependent kinase 4 (CDK4) gene. Interestingly, previous studies from our laboratory showed that the overexpression of CDK4 led to keratinocyte hyperproliferation, although no spontaneous tumor development was observed. Thus, we tested the hypothesis that CDK4 may be one of the critical downstream genes involved in Myc carcinogenesis. Our results showed that CDK4 inhibition in K5-Myc transgenic mice resulted in the complete inhibition of tumor development, suggesting that CDK4 is a critical mediator of tumor formation induced by deregulated Myc. Furthermore, a lack of CDK4 expression resulted in marked decreases in epidermal thickness and keratinocyte proliferation compared to the results obtained for K5-Myc littermates. Biochemical analysis of the K5-Myc epidermis showed that CDK4 mediates the proliferative activities of Myc by sequestering p21Cip1 and p27Kip1 and thereby indirectly activating CDK2 kinase activity. These results show that CDK4 mediates the proliferative and oncogenic activities of Myc in vivo through a mechanism that involves the sequestration of specific CDK inhibitors.

  14. Tissue microarray analysis for epithelial membrane protein-2 as a novel biomarker for gliomas.

    PubMed

    Chung, Lawrance K; Pelargos, Panayiotis E; Chan, Ann M; Demos, Joanna V; Lagman, Carlito; Sheppard, John P; Nguyen, Thien; Chang, Yu-Ling; Hojat, Seyed A; Prins, Robert M; Liau, Linda M; Nghiemphu, Leia; Lai, Albert; Cloughesy, Timothy F; Yong, William H; Gordon, Lynn K; Wadehra, Madhuri; Yang, Isaac

    2017-09-08

    Epithelial membrane protein-2 (EMP2) expression is noted in many human cancers. We evaluated EMP2 as a biomarker in gliomas. A large tissue microarray of lower grade glioma (WHO grades II-III, n = 19 patients) and glioblastoma (GBM) (WHO grade IV, n = 50 patients) was stained for EMP2. EMP2 expression was dichotomized to low or high expression scores and correlated with clinical data. The mean EMP2 expression was 1.68 in lower grade gliomas versus 2.20 in GBMs (P = 0.01). The percentage of samples with high EMP2 expression was greater in GBMs than lower grade gliomas (90.0 vs. 52.6%, P = 0.001). No significant difference was found between median survival among patients with GBM tumors exhibiting high EMP2 expression and survival of those with low EMP2 expression (8.38 vs. 10.98 months, P = 0.39). However, EMP2 expression ≥2 correlated with decreased survival (r = -0.39, P = 0.001). The EMP2 expression level also correlated with Ki-67 positivity (r = 0.34, P = 0.008). The mortality hazard ratio for GBM patients with EMP2 score of 3 or higher was 1.92 (CI 0.69-5.30). Our findings suggest that elevated EMP2 expression is associated with GBM. With other biomarkers, EMP2 may have use as a molecular target for the diagnosis and treatment of gliomas.

  15. LncRNA-HOST2 regulates cell biological behaviors in epithelial ovarian cancer through a mechanism involving microRNA let-7b.

    PubMed

    Gao, Yuan; Meng, Hao; Liu, Shupeng; Hu, Jingjing; Zhang, Yemin; Jiao, Tingting; Liu, Yujie; Ou, Jun; Wang, Dan; Yao, Lin; Liu, Shanrong; Hui, Ning

    2015-02-01

    Recently, a large number of long non-coding RNAs (lncRNAs) have been reported in mammalian genomes and are evolutionarily conserved and presumably function in many biological events, especially in the pathogenesis of diverse human cancers. A lncRNA, named HOST2 (human ovarian cancer-specific transcript 2), was once reported to specifically be expressed at high level in human ovarian cancer. However, how HOST2 acts to regulate gene functions in ovarian carcinogenesis has remained enigmatic. Here we report, for the first time, that HOST2 promotes tumor cell migration, invasion and proliferation in epithelial ovarian cancer by working in key aspects of biological behaviors. In the present study, bioinformatics analysis indicated that HOST2 binds with microRNA let-7b, a potent tumor suppressor, which was then verified to target HOST2. Our results showed that HOST2 harbors a let-7b binding site and modulates let-7b availability by acting as a molecular sponge. HOST2 inhibits let-7b functions, which post-transcriptionally suppress the expression of targets, including some oncogenes that regulate cell growth and motility. Additionally, understanding HOST2/let-7b-dependent regulation may lead to alternative approaches for the diagnosis and cure of this deadly disease. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Chlamydia trachomatis Is Resistant to Inclusion Ubiquitination and Associated Host Defense in Gamma Interferon-Primed Human Epithelial Cells

    PubMed Central

    Haldar, Arun K.; Piro, Anthony S.; Finethy, Ryan; Espenschied, Scott T.; Brown, Hannah E.; Giebel, Amanda M.; Frickel, Eva-Maria; Nelson, David E.

    2016-01-01

    ABSTRACT The cytokine gamma interferon (IFN-γ) induces cell-autonomous immunity to combat infections with intracellular pathogens, such as the bacterium Chlamydia trachomatis. The present study demonstrates that IFN-γ-primed human cells ubiquitinate and eliminate intracellular Chlamydia-containing vacuoles, so-called inclusions. We previously described how IFN-γ-inducible immunity-related GTPases (IRGs) employ ubiquitin systems to mark inclusions for destruction in mouse cells and, furthermore, showed that the rodent pathogen Chlamydia muridarum blocks ubiquitination of its inclusions by interfering with mouse IRG function. Here, we report that ubiquitination of inclusions in human cells is independent of IRG and thus distinct from the murine pathway. We show that C. muridarum is susceptible to inclusion ubiquitination in human cells, while the closely related human pathogen C. trachomatis is resistant. C. muridarum, but not C. trachomatis, inclusions attract several markers of cell-autonomous immunity, including the ubiquitin-binding protein p62, the ubiquitin-like protein LC3, and guanylate-binding protein 1. Consequently, we find that IFN-γ priming of human epithelial cells triggers the elimination of C. muridarum, but not C. trachomatis, inclusions. This newly described defense pathway is independent of indole-2,3-dioxygenase, a known IFN-γ-inducible anti-Chlamydia resistance factor. Collectively, our observations indicate that C. trachomatis evolved mechanisms to avoid a human-specific, ubiquitin-mediated response as part of its unique adaptation to its human host. PMID:27965446

  17. Chlamydia trachomatis Is Resistant to Inclusion Ubiquitination and Associated Host Defense in Gamma Interferon-Primed Human Epithelial Cells.

    PubMed

    Haldar, Arun K; Piro, Anthony S; Finethy, Ryan; Espenschied, Scott T; Brown, Hannah E; Giebel, Amanda M; Frickel, Eva-Maria; Nelson, David E; Coers, Jörn

    2016-12-13

    The cytokine gamma interferon (IFN-γ) induces cell-autonomous immunity to combat infections with intracellular pathogens, such as the bacterium Chlamydia trachomatis The present study demonstrates that IFN-γ-primed human cells ubiquitinate and eliminate intracellular Chlamydia-containing vacuoles, so-called inclusions. We previously described how IFN-γ-inducible immunity-related GTPases (IRGs) employ ubiquitin systems to mark inclusions for destruction in mouse cells and, furthermore, showed that the rodent pathogen Chlamydia muridarum blocks ubiquitination of its inclusions by interfering with mouse IRG function. Here, we report that ubiquitination of inclusions in human cells is independent of IRG and thus distinct from the murine pathway. We show that C. muridarum is susceptible to inclusion ubiquitination in human cells, while the closely related human pathogen C. trachomatis is resistant. C. muridarum, but not C. trachomatis, inclusions attract several markers of cell-autonomous immunity, including the ubiquitin-binding protein p62, the ubiquitin-like protein LC3, and guanylate-binding protein 1. Consequently, we find that IFN-γ priming of human epithelial cells triggers the elimination of C. muridarum, but not C. trachomatis, inclusions. This newly described defense pathway is independent of indole-2,3-dioxygenase, a known IFN-γ-inducible anti-Chlamydia resistance factor. Collectively, our observations indicate that C. trachomatis evolved mechanisms to avoid a human-specific, ubiquitin-mediated response as part of its unique adaptation to its human host.

  18. Development of an Autonomous, Dual Chamber Bioreactor for the Growth of 3-Dimensional Epithelial-Stromal Tissues in Microgravity

    NASA Technical Reports Server (NTRS)

    Patel, Zarana S.; Wettergreen, Matthew A.; Huff, Janice L.

    2014-01-01

    We are developing a novel, autonomous bioreactor that can provide for the growth and maintenance in microgravity of 3-D organotypic epithelial-stromal cultures that require an air-liquid interface. These complex 3-D tissue models accurately represent the morphological features, differentiation markers, and growth characteristics observed in normal human epithelial tissues, including the skin, esophagus, lung, breast, pancreas, and colon. However, because of their precise and complex culture requirements, including that of an air-liquid interface, these 3-D models have yet to be utilized for life sciences research aboard the International Space Station. The development of a bioreactor for these cultures will provide the capability to perform biological research on the ISS using these realistic, tissue-like human epithelial-stromal cell models and will contribute significantly to advances in fundamental space biology research on questions regarding microgravity effects on normal tissue development, aging, cancer, and other disease processes. It will also allow for the study of how combined stressors, such as microgravity with radiation and nutritional deficiencies, affect multiple biological processes and will provide a platform for conducting countermeasure investigations on the ISS without the use of animal models. The technology will be autonomous and consist of a cell culture chamber that provides for air-liquid, liquid-liquid, and liquid-air exchanges within the chambers while maintaining the growth and development of the biological samples. The bioreactor will support multiple tissue types and its modular design will provide for incorporation of add-on capabilities such as microfluidics drug delivery, media sampling, and in situ biomarker analysis. Preliminary flight testing of the hardware will be conducted on a parabolic platform through NASA's Flight Opportunities Program.

  19. Markers of fibrosis and epithelial to mesenchymal transition demonstrate field cancerization in histologically normal tissue adjacent to breast tumors

    PubMed Central

    Trujillo, Kristina A.; Heaphy, Christopher M.; Mai, Minh; Vargas, Keith M.; Jones, Anna C.; Vo, Phung; Butler, Kimberly S.; Joste, Nancy E.; Bisoffi, Marco; Griffith, Jeffrey K

    2011-01-01

    Previous studies have shown that a field of genetically altered but histologically normal tissue extends 1 cm or more from the margins of human breast tumors. The extent, composition and biological significance of this field are only partially understood, but the molecular alterations in affected cells could provide mechanisms for limitless replicative capacity, genomic instability and a microenvironment that supports tumor initiation and progression. We demonstrate by microarray, qRT-PCR and immunohistochemistry a signature of differential gene expression that discriminates between patient-matched, tumor-adjacent histologically normal breast tissues located 1 cm and 5 cm from the margins of breast adenocarcinomas (TAHN-1 and TAHN-5, respectively). The signature includes genes involved in extracellular matrix remodeling, wound healing, fibrosis and epithelial to mesenchymal transition (EMT). Myofibroblasts, which are mediators of wound healing and fibrosis, and intra-lobular fibroblasts expressing MMP2, SPARC, TGF-β3, which are inducers of EMT, were both prevalent in TAHN-1 tissues, sparse in TAHN-5 tissues, and absent in normal tissues from reduction mammoplasty. Accordingly, EMT markers S100A4 and vimentin were elevated in both luminal and myoepithelial cells, and EMT markers α-smooth muscle actin and SNAIL were elevated in luminal epithelial cells of TAHN-1 tissues. These results identify cellular processes that are differentially activated between TAHN-1 and TAHN-5 breast tissues, implicate myofibroblasts as likely mediators of these processes, provide evidence that EMT is occurring in histologically normal tissues within the affected field and identify candidate biomarkers to investigate whether or how field cancerization contributes to the development of primary or recurrent breast tumors. PMID:21105047

  20. Combinatorial biomatrix/cell-based therapies for restoration of host tissue architecture and function

    PubMed Central

    Cantu, David Antonio; Kao, W. John

    2014-01-01

    This Progress Report reviews recent advances in the utility of extracellular matrix (ECM)-mimic biomaterials in presenting and delivering therapeutic cells to promote tissue healing. This overview gives a brief introduction of different cell types being used in regenerative medicine and tissue engineering while addressing critical issues that must be overcome before cell-based approaches can be routinely employed in the clinic. A selection of 5 commonly used cell-associated, biomaterial platforms (collagen, hyaluronic acid, fibrin, alginate, and poly(ethylene glycol)) are reviewed for treatment of a number of acute injury or diseases with emphasis on animal models and clinical trials. This article concludes with current challenges and future perspectives regarding foreign body host response to biomaterials and immunological reactions to allogeneic or xenogeneic cells, vascularization and angiogenesis, matching mechanical strength and anisotropy of native tissues, as well as other non-technical issues regarding the clinical translation of biomatrix/cell-based therapies. PMID:23828863

  1. YAP Regulates the Expression of Hoxa1 and Hoxc13 in Mouse and Human Oral and Skin Epithelial Tissues

    PubMed Central

    Liu, Ming; Zhao, Shuangyun; Lin, Qingjie

    2015-01-01

    Yes-associated protein (YAP) is a Hippo signaling transcriptional coactivator that plays pivotal roles in stem cell proliferation, organ size control, and tumor development. The downstream targets of YAP have been shown to be highly context dependent. In this study, we used the embryonic mouse tooth germ as a tool to search for the downstream targets of YAP in ectoderm-derived tissues. Yap deficiency in the dental epithelium resulted in a small tooth germ with reduced epithelial cell proliferation. We compared the gene expression profiles of embryonic day 14.5 (E14.5) Yap conditional knockout and YAP transgenic mouse tooth germs using transcriptome sequencing (RNA-Seq) and further confirmed the differentially expressed genes using real-time PCR and in situ hybridization. We found that YAP regulates the expression of Hoxa1 and Hoxc13 in oral and dental epithelial tissues as well as in the epidermis of skin during embryonic and adult stages. Sphere formation assay suggested that Hoxa1 and Hoxc13 are functionally involved in YAP-regulated epithelial progenitor cell proliferation, and chromatin immunoprecipitation (ChIP) assay implies that YAP may regulate Hoxa1 and Hoxc13 expression through TEAD transcription factors. These results provide mechanistic insights into abnormal YAP activities in mice and humans. PMID:25691658

  2. Carcinoma Initiation via Rb Tumor Suppressor Inactivation: A Versatile Approach to Epithelial Subtype-Dependent Cancer Initiation in Diverse Tissues

    PubMed Central

    Song, Yurong; Gilbert, Debra; O’Sullivan, T. Norene; Yang, Chunyu; Pan, Wenqi; Fathalizadeh, Alisan; Lu, Lucy; Haines, Diana C.; Martin, Philip L.; Van Dyke, Terry

    2013-01-01

    Carcinomas arise in a complex microenvironment consisting of multiple distinct epithelial lineages surrounded by a variety of stromal cell types. Understanding cancer etiologies requires evaluating the relationship among cell types during disease initiation and through progression. Genetically engineered mouse (GEM) models facilitate the prospective examination of early oncogenic events, which is not possible in humans. Since most solid tumors harbor aberrations in the RB network, we developed an inducible GEM approach for the establishment and assessment of carcinoma initiation in a diverse range of epithelial tissues and subtypes upon inactivation of RB-mediated tumor suppression (RB-TS). The system allows independent assessment of epithelial subtypes that express either cytokeratins (K) 18 or 19. By Cre-dependent expression of a protein that dominantly inactivates RB and functionally redundant proteins p107 and p130, neoplasia could be initiated in either K18 or K19 expressing cells of numerous tissues. By design, because only a single pathway aberration was engineered, carcinomas developed stochastically only after long latency. Hence, this system, which allows for directed cell type-specific carcinoma initiation, facilitates further definition of events that can progress neoplasms to aggressive cancers via engineered, carcinogen-induced and/or spontaneous evolution. PMID:24312475

  3. YAP regulates the expression of Hoxa1 and Hoxc13 in mouse and human oral and skin epithelial tissues.

    PubMed

    Liu, Ming; Zhao, Shuangyun; Lin, Qingjie; Wang, Xiu-Ping

    2015-04-01

    Yes-associated protein (YAP) is a Hippo signaling transcriptional coactivator that plays pivotal roles in stem cell proliferation, organ size control, and tumor development. The downstream targets of YAP have been shown to be highly context dependent. In this study, we used the embryonic mouse tooth germ as a tool to search for the downstream targets of YAP in ectoderm-derived tissues. Yap deficiency in the dental epithelium resulted in a small tooth germ with reduced epithelial cell proliferation. We compared the gene expression profiles of embryonic day 14.5 (E14.5) Yap conditional knockout and YAP transgenic mouse tooth germs using transcriptome sequencing (RNA-Seq) and further confirmed the differentially expressed genes using real-time PCR and in situ hybridization. We found that YAP regulates the expression of Hoxa1 and Hoxc13 in oral and dental epithelial tissues as well as in the epidermis of skin during embryonic and adult stages. Sphere formation assay suggested that Hoxa1 and Hoxc13 are functionally involved in YAP-regulated epithelial progenitor cell proliferation, and chromatin immunoprecipitation (ChIP) assay implies that YAP may regulate Hoxa1 and Hoxc13 expression through TEAD transcription factors. These results provide mechanistic insights into abnormal YAP activities in mice and humans.

  4. Transforming growth factor-alpha in vivo stimulates epithelial cell proliferation in digestive tissues of suckling rats.

    PubMed Central

    Hormi, K; Lehy, T

    1996-01-01

    BACKGROUND: The role that exogenous transforming growth factor-alpha (TGF-alpha) may exert on cell proliferation in vivo is poorly understood. AIM: To investigate the effect of rat TGF-alpha on epithelial cell proliferation in all suckling rat digestive tissues and to compare it with that of rat epidermal growth factor (EGF). ANIMAL AND METHODS: TGF-alpha and EGF were given three times daily either subcutaneously (10 or 20 micrograms/kg) or intraperitoneally (100 micrograms/kg) to rats from the ninth postnatal day. Cell proliferation was assessed through 5-bromo- 2-deoxyuridine incorporation and estimation of labelling indices. RESULTS: For both growth factors, the highest dose given for only two days significantly increased stomach and intestinal weights compared with controls (p < 0.05 to p < 0.001). The proliferative responded depended on the dose given, colonic mucosa being the most sensitive whereas oxyntic mucosa remained unresponsive. TGF-alpha was as potent as EGF in stimulating epithelial cell proliferation in antral, duodenal, and colonic mucosae. However, EGF was more active on oesophageal and jejunal cell proliferation whereas TGF-alpha was more active on pancreatic exocrine cell proliferation and the differences between the two growth factor treated groups were significant. CONCLUSIONS: These results prove for the first time the stimulating effect in vivo of exogenous rat TGF-alpha on epithelial cell proliferation in rat digestive tissues during the developmental period and support a functional role for TGF-alpha at that time. PMID:8944561

  5. The role of L-type amino acid transporters in the uptake of glyphosate across mammalian epithelial tissues.

    PubMed

    Xu, Jiaqiang; Li, Gao; Wang, Zhuoyi; Si, Luqin; He, Sijie; Cai, Jialing; Huang, Jiangeng; Donovan, Maureen D

    2016-02-01

    Glyphosate is one of the most commonly used herbicides worldwide due to its broad spectrum of activity and reported low toxicity to humans. Glyphosate has an amino acid-like structure that is highly polar and shows low bioavailability following oral ingestion and low systemic toxicity following intravenous exposures. Spray applications of glyphosate in agricultural or residential settings can result in topical or inhalation exposures to the herbicide. Limited systemic exposure to glyphosate occurs following skin contact, and pulmonary exposure has also been reported to be low. The results of nasal inhalation exposures, however, have not been evaluated. To investigate the mechanisms of glyphosate absorption across epithelial tissues, the permeation of glyphosate across Caco-2 cells, a gastrointestinal epithelium model, was compared with permeation across nasal respiratory and olfactory tissues excised from cows. Saturable glyphosate uptake was seen in all three tissues, indicating the activity of epithelial transporters. The uptake was shown to be ATP and Na(+) independent, and glyphosate permeability could be significantly reduced by the inclusion of competitive amino acids or specific LAT1/LAT2 transporter inhibitors. The pattern of inhibition of glyphosate permeability across Caco-2 and nasal mucosal tissues suggests that LAT1/2 play major roles in the transport of this amino-acid-like herbicide. Enhanced uptake into the epithelial cells at barrier mucosae, including the respiratory and gastrointestinal tracts, may result in more significant local and systemic effects than predicted from glyphosate's passive permeability, and enhanced uptake by the olfactory mucosa may result in further CNS disposition, potentially increasing the risk for brain-related toxicities. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Protein profiling of isolated leukocytes, myofibroblasts, epithelial, Basal, and endothelial cells from normal, hyperplastic, cancerous, and inflammatory human prostate tissues.

    PubMed

    Khamis, Zahraa I; Iczkowski, Kenneth A; Sahab, Ziad J; Sang, Qing-Xiang Amy

    2010-06-15

    In situ neoplastic prostate cells are not lethal unless they become invasive and metastatic. For cells to become invasive, the prostate gland must undergo degradation of the basement membrane and disruption of the basal cell layer underneath the luminal epithelia. Although the roles of proteinases in breaking down the basement membrane have been well-studied, little is known about the factors that induce basal cell layer disruption, degeneration, and its eventual disappearance in invasive cancer. It is hypothesized that microenvironmental factors may affect the degradation of the basal cell layer, which if protected may prevent tumor progression and invasion. In this study, we have revealed differential protein expression patterns between epithelial and stromal cells isolated from different prostate pathologies and identified several important epithelial and stromal proteins that may contribute to inflammation and malignant transformation of human benign prostate tissues to cancerous tissues using matrix-assisted laser desorption ionization time-of-flight mass spectrometry and proteomics methods. Cellular retinoic acid-binding protein 2 was downregulated in basal cells of benign prostate. Caspase-1 and interleukin-18 receptor 1 were highly expressed in leukocytes of prostate cancer. Proto-oncogene Wnt-3 was downregulated in endothelial cells of prostatitis tissue and tyrosine phosphatase non receptor type 1 was only found in normal and benign endothelial cells. Poly ADP-ribose polymerase 14 was downregulated in myofibroblasts of prostatitis tissue. Interestingly, integrin alpha-6 was upregulated in epithelial cells but not detected in myofibroblasts of prostate cancer. Further validation of these proteins may generate new strategies for the prevention of basal cell layer disruption and subsequent cancer invasion.

  7. Host origin and tissue microhabitat shaping the microbiota of the terrestrial isopod Armadillidium vulgare.

    PubMed

    Dittmer, Jessica; Lesobre, Jérôme; Moumen, Bouziane; Bouchon, Didier

    2016-05-01

    We present the first in-depth investigation of the host-associated microbiota of the terrestrial isopod crustacean Armadillidium vulgare. This species is an important decomposer of organic matter in terrestrial ecosystems and a major model organism for arthropod-Wolbachia symbioses due to its well-characterized association with feminizing Wolbachia 16S rRNA gene pyrotags were used to characterize its bacterial microbiota at multiple levels: (i) in individuals from laboratory lineages and field populations and (ii) in various host tissues. This integrative approach allowed us to reveal an unexpectedly high bacterial diversity, placing this species in the same league as termites in terms of symbiotic diversity. Interestingly, both animal groups belong to the same ecological guild in terrestrial ecosystems. While Wolbachia represented the predominant taxon in infected individuals, it was not the only major player. Together, the most abundant taxa represented a large scope of symbiotic interactions, including bacterial pathogens, a reproductive parasite (Wolbachia) and potential nutritional symbionts. Furthermore, we demonstrate that individuals from different populations harboured distinct bacterial communities, indicating a strong link between the host-associated microbiota and environmental bacteria, possibly due to terrestrial isopod nutritional ecology. Overall, this work highlights the need for more studies of host-microbiota interactions and bacterial diversity in non-insect arthropods.

  8. Pseudomonas aeruginosa Outer Membrane Vesicles Triggered by Human Mucosal Fluid and Lysozyme Can Prime Host Tissue Surfaces for Bacterial Adhesion

    PubMed Central

    Metruccio, Matteo M. E.; Evans, David J.; Gabriel, Manal M.; Kadurugamuwa, Jagath L.; Fleiszig, Suzanne M. J.

    2016-01-01

    Pseudomonas aeruginosa is a leading cause of human morbidity and mortality that often targets epithelial surfaces. Host immunocompromise, or the presence of indwelling medical devices, including contact lenses, can predispose to infection. While medical devices are known to accumulate bacterial biofilms, it is not well understood why resistant epithelial surfaces become susceptible to P. aeruginosa. Many bacteria, including P. aeruginosa, release outer membrane vesicles (OMVs) in response to stress that can fuse with host cells to alter their function. Here, we tested the hypothesis that mucosal fluid can trigger OMV release to compromise an epithelial barrier. This was tested using tear fluid and corneal epithelial cells in vitro and in vivo. After 1 h both human tear fluid, and the tear component lysozyme, greatly enhanced OMV release from P. aeruginosa strain PAO1 compared to phosphate buffered saline (PBS) controls (∼100-fold). Transmission electron microscopy (TEM) and SDS-PAGE showed tear fluid and lysozyme-induced OMVs were similar in size and protein composition, but differed from biofilm-harvested OMVs, the latter smaller with fewer proteins. Lysozyme-induced OMVs were cytotoxic to human corneal epithelial cells in vitro and murine corneal epithelium in vivo. OMV exposure in vivo enhanced Ly6G/C expression at the corneal surface, suggesting myeloid cell recruitment, and primed the cornea for bacterial adhesion (∼4-fold, P < 0.01). Sonication disrupted OMVs retained cytotoxic activity, but did not promote adhesion, suggesting the latter required OMV-mediated events beyond cell killing. These data suggest that mucosal fluid induced P. aeruginosa OMVs could contribute to loss of epithelial barrier function during medical device-related infections. PMID:27375592

  9. Major Host Factors Involved in Epithelial Cell Invasion of Campylobacter jejuni: Role of Fibronectin, Integrin Beta1, FAK, Tiam-1, and DOCK180 in Activating Rho GTPase Rac1

    PubMed Central

    Boehm, Manja; Krause-Gruszczynska, Malgorzata; Rohde, Manfred; Tegtmeyer, Nicole; Takahashi, Seiichiro; Oyarzabal, Omar A.; Backert, Steffen

    2011-01-01

    Host cell entry by the food-borne pathogen Campylobacter jejuni has been reported as one of the primary reasons of tissue damage in infected humans, however, molecular invasion mechanisms and cellular factors involved in this process are widely unclear. Here we used knockout cell lines derived from fibronectin−/−, integrin beta1−/−, and focal adhesion kinase (FAK)−/− deficient mice and corresponding wild-type (WT) controls, to study C. jejuni-induced signaling cascades involved in the bacterial invasion process. Using high resolution scanning electron microscopy, GTPase pull-downs, G-LISA, and gentamicin protection assays we found that each of these host cell factors is indeed required for activation of the small Rho GTPase member Rac1 and maximal host cell invasion of this pathogen. Interestingly, membrane ruffling, tight engulfment of bacteria and invasion were only seen during infection of WT control cells, but not in fibronectin−/−, integrin beta1−/−, and FAK−/− knockout cell lines. We also demonstrate that C. jejuni activates FAK autophosphorylation activity at Y-397 and phosphorylation of Y-925, which is required for stimulating two downstream guanine exchange factors, DOCK180 and Tiam-1, which are upstream of Rac1. Small interfering (si) RNA studies further show that DOCK180 and Tiam-1 act cooperatively to trigger Rac1 activation and C. jejuni invasion. Moreover, mutagenesis data indicate that the bacterial fibronectin-binding protein CadF and the intact flagellum are involved in Rho GTPase activation and host cell invasion. Collectively, our results suggest that C. jejuni infection of host epithelial target cells hijacks a major fibronectin → integrin beta1 → FAK → DOCK180/Tiam-1 signaling cascade, which has a crucial role for Rac1 GTPase activity and bacterial entry into host target cells. PMID:22919583

  10. Perioperative steroid administration inhibits angiogenic host tissue response to porous polyethylene (Medpor) implants.

    PubMed

    Ehrmantraut, S; Laschke, M W; Merkel, D; Scheuer, C; Willnecker, V; Meyer-Lindenberg, A; Menger, M D; Naumann, A

    2010-02-26

    Porous polyethylene (Medpor) is an alloplastic biomaterial, which is commonly used in plastic and reconstructive surgery. In the present study, we analyzed the effect of perioperative steroid administration on the inflammatory and angiogenic host tissue response to implanted Medpor. For this purpose, Medpor was implanted into the dorsal skinfold chamber of prednisolone-treated and vehicle-treated (control) balb/c mice and analyzed by means of intravital fluorescence microscopy over a 14-day period. Incorporation of the implants was evaluated by histology. An aortic ring assay and Western blot analyses were performed to determine in vitro the effect of prednisolone on angiogenesis. Implantation of Medpor did not induce a leukocytic inflammatory host tissue response. However, in prednisolone-treated and control animals giant cells could be detected at the interface between the implants and the surrounding granulation tissue as a typical indicator for a chronic foreign body reaction. Interestingly, perioperative prednisolone administration inhibited vascularisation of the implants, as indicated by a significantly decreased functional density of newly developing capillary blood vessels. Accordingly, prednisolone suppressed in vitro endothelial sprouting and tube formation in the aortic ring assay and reduced proliferating cell nuclear antigen (PCNA), Tie2, vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)-9 expression of murine endothelioma cells. In conclusion, prednisolone treatment inhibits the early vascularisation of Medpor implants due to direct inhibition of distinct angiogenic mechanisms. Therefore, perioperative steroid therapy should be avoided in case of Medpor implantation to achieve a rapid incorporation of the biomaterial at the implantation site.

  11. Immunolocalization of cyclotides in plant cells, tissues and organ supports their role in host defense.

    PubMed

    Slazak, Blazej; Kapusta, Małgorzata; Malik, Sohaib; Bohdanowicz, Jerzy; Kuta, Elżbieta; Malec, Przemysław; Göransson, Ulf

    2016-11-01

    The distribution of cyclotides was visualized in plant cells, tissues and organs using immunohistochemistry. Finding of cyclotides in tissues potentially vulnerable to pathogen attacks supports their role as defense molecules. The cyclotide family of plant peptides is characterized by the cyclic cystine knot motif and its diverse biological activities. Given their insecticidal and antimicrobial properties, the role of cyclotides in planta is probably associated with host defense. Our current understanding of the cellular compartmentalization of cyclotides in the vacuole is based on indirect studies on transgenic model plants that do not express cyclotides naturally. Matrix-assisted laser desorption ionization (MALDI) imaging has also been used to study the distribution of cyclotides, but the technique's resolution was insufficient to determine their tissue or cell distribution. To avoid the limitations of these approaches, immunohistochemical visualization methods were used. Antibodies were raised in rabbits using cycloviolacin O2 (cyO2), and their specificity was determined by Western and dot blot experiments. Slides for immunohistochemical analysis were prepared from leaf, petiole and root fragments of Viola odorata and Viola uliginosa, and specimens were visualized using indirect epifluorescence microscopy. The antibodies against cyclotides were specific against selected bracelet cyclotides with high similarity (cyO2, cyO3, cyO8, cyO13) and suitable for immunohistochemistry. The tissue distribution of the cyclotides visualized in this way is consistent with their proposed role in host defense-relatively large quantities were observed in the leaf and petiole epidermis in both Viola species. Cyclotides were also found in vascular tissue in all the assessed plant organs. The vacuole storage of cyclotides was directly shown.

  12. Chemically-defined medium for growth and differentiation of mixed epithelial and connective tissues in organ culture.

    PubMed

    Hodges, G M; Melcher, A H

    1976-06-01

    The effect on tissue differentiation and growth in vitro of certain of the factors implicated in collagen synthesis (ascorbic acid, alpha-ketoglutarate and oxygen) and the influence of hydrocortisone was studied using organ cultures of fetal mouse mandible as a mixed epithelial and connective tissue system. Using serum-free Waymouth's MB 752/1 chemically-defined medium, addition of high levels of ascorbic acid (300mug per ml), hydrocortisone (1mug per ml) and oxygen (95%) enhanced differentiation in a number of tissues, in particular skin and appendages, tooth germs and bone, while osteoid and dentine production were noticeable promoted. It is suggested that an essential aspect of media design for organ culture involves the incorporaation of collagen-promoting factors to the in vitro enviornment particularly with regard to the controlling role implicated for collagen in a variety of biological processess.

  13. PilY1 Promotes Legionella pneumophila Infection of Human Lung Tissue Explants and Contributes to Bacterial Adhesion, Host Cell Invasion, and Twitching Motility

    PubMed Central

    Hoppe, Julia; Ünal, Can M.; Thiem, Stefanie; Grimpe, Louisa; Goldmann, Torsten; Gaßler, Nikolaus; Richter, Matthias; Shevchuk, Olga; Steinert, Michael

    2017-01-01

    Legionnaires' disease is an acute fibrinopurulent pneumonia. During infection Legionella pneumophila adheres to the alveolar lining and replicates intracellularly within recruited macrophages. Here we provide a sequence and domain composition analysis of the L. pneumophila PilY1 protein, which has a high homology to PilY1 of Pseudomonas aeruginosa. PilY1 proteins of both pathogens contain a von Willebrand factor A (vWFa) and a C-terminal PilY domain. Using cellular fractionation, we assigned the L. pneumophila PilY1 as an outer membrane protein that is only expressed during the transmissive stationary growth phase. PilY1 contributes to infection of human lung tissue explants (HLTEs). A detailed analysis using THP-1 macrophages and A549 lung epithelial cells revealed that this contribution is due to multiple effects depending on host cell type. Deletion of PilY1 resulted in a lower replication rate in THP-1 macrophages but not in A549 cells. Further on, adhesion to THP-1 macrophages and A549 epithelial cells was decreased. Additionally, the invasion into non-phagocytic A549 epithelial cells was drastically reduced when PilY1 was absent. Complementation variants of a PilY1-negative mutant revealed that the C-terminal PilY domain is essential for restoring the wild type phenotype in adhesion, while the putatively mechanosensitive vWFa domain facilitates invasion into non-phagocytic cells. Since PilY1 also promotes twitching motility of L. pneumophila, we discuss the putative contribution of this newly described virulence factor for bacterial dissemination within infected lung tissue. PMID:28326293

  14. Flow cytometric determination of stem/progenitor content in epithelial tissues: an example from nonsmall lung cancer and normal lung.

    PubMed

    Donnenberg, Vera S; Landreneau, Rodney J; Pfeifer, Melanie E; Donnenberg, Albert D

    2013-01-01

    Single cell analysis and cell sorting has enabled the study of development, growth, differentiation, repair and maintenance of "liquid" tissues and their cancers. The application of these methods to solid tissues is equally promising, but several unique technical challenges must be addressed. This report illustrates the application of multidimensional flow cytometry to the identification of candidate stem/progenitor populations in non-small cell lung cancer and paired normal lung tissue. Seventeen paired tumor/normal lung samples were collected at the time of surgical excision and processed immediately. Tissues were mechanically and enzymatically dissociated into single cell suspension and stained with a panel of antibodies used for negative gating (CD45, CD14, CD33, glycophorin A), identification of epithelial cells (intracellular cytokeratin), and detection of stem/progenitor markers (CD44, CD90, CD117, CD133). DAPI was added to measure DNA content. Formalin fixed paraffin embedded tissue samples were stained with key markers (cytokeratin, CD117, DAPI) for immunofluorescent tissue localization of populations detected by flow cytometry. Disaggregated tumor and lung preparations contained a high proportion of events that would interfere with analysis, were they not eliminated by logical gating. We demonstrate how inclusion of doublets, events with hypodiploid DNA, and cytokeratin+ events also staining for hematopoietic markers reduces the ability to quantify epithelial cells and their precursors. Using the lung cancer/normal lung data set, we present an approach to multidimensional data analysis that consists of artifact removal, identification of classes of cells to be studied further (classifiers) and the measurement of outcome variables on these cell classes. The results of bivariate analysis show a striking similarity between the expression of stem/progenitor markers on lung tumor and adjacent tumor-free lung.

  15. Morphological and Ultrastructural Changes in Tissues of Intermediate and Definitive Hosts Infected by Protostrongylid Lungworms (Nematoda: Metastrongyloidea)

    USDA-ARS?s Scientific Manuscript database

    Cellular and sub-cellular mechanisms involved in tissue responses to larval and adult lungworms (Protostrongylidae) were respectively explored through experimental and natural infections in molluscan intermediate (Xeropicta candacharica) and ruminant definitive hosts (Ovis aries). Reaction to develo...

  16. Development of resistance with host age to adhesion of K99+ Escherichia coli to isolated intestinal epithelial cells.

    PubMed Central

    Runnels, P L; Moon, H W; Schneider, R A

    1980-01-01

    When isolated intestinal epithelial cells from neonatal and older pigs, calves, and mice were tested for adhesion by K99+ enterotoxigenic Escherichia coli, cells from older animals were resistant to adhesion. PMID:6103878

  17. Expression of transcription factors Slug in the lens epithelial cells undergoing epithelial-mesenchymal transition induced by connective tissue growth factor

    PubMed Central

    Wang, Ying-Na; Qin, Li; Li, Jing-Ming; Chen, Li; Pei, Cheng

    2015-01-01

    AIM To investigate the expression of transcription factors Slug in human lens epithelial cells (HLECs) undergoing epithelial-mesenchymal transition (EMT) induced by connective tissue growth factor (CTGF). METHODS HLECs were treated with CTGF of different concentrations (20, 50 and 100 ng/mL) or without CTGF (control) for 24h. The morphological changes of HLECs were analysed by microscopy. The expression and cellular localization of Slug was evaluated by immumo-fluorescence. Expressions of Slug, E-cadherin and alpha smooth muscle actin (α-SMA) were further determined by Western blot analysis. RESULTS HLECs showed spidle fibrolasts-like characteristics and loosely connected each other after CTGF treatment. The immuno-fluorescence staining indicated that Slug was localized in the nuclei and its expression was induced by CTGF. The relative expressions of Slug protein were 1.64±0.11, 1.96 ±0.03, 3.12 ±0.10, and 4.08±0.14, respectively, in response to control group and treatment with CTGF of 20, 50 and 100 ng/mL (F=443.86, P<0.01). The increased Slug protein levels were correlated well with up-expression of α-SMA (0.78±0.05, 0.85±0.06, 2.17±0.15, 2.86±0.10; F=449.85, P<0.01) and down-expression of E-cadherin (2.50±0.11, 1.79±0.26, 1.05±0.14, 0.63±0.08; F=101.55, P<0.01). CONCLUSION Transcription factor Slug may be involved in EMT of HLECs induced by CTGF in vitro. PMID:26558194

  18. Increased fractal complexity of the epithelial-connective tissue interface in the tongue of 4NQO-treated rats.

    PubMed

    Landini, G; Hirayama, Y; Li, T J; Kitano, M

    2000-01-01

    The effect of the carcinogen 4-nitroquinoline 1-oxide (0.001% in drinking water) on the irregularity of the epithelial connective tissue interface (ECTI) of the ventral surface of the tongue was quantified in Dark Agouti and Wistar Furth rats. Histological tongue sections stained with the Azan-Mallory method were digitised (111 images, resolution 1 pixel = 3.1 microns), and the limit between epithelium and stroma of the ventral surface was extracted and analysed using a fractal geometry technique (local connected dimension). The results showed that although none of the images included carcinomas on the ventral surface of the tongue (all cases had other oral carcinomas), the epithelial profiles of the treated cases showed a statistically significant increase in irregularity when compared to controls. Canonical discriminant analysis of the parameters describing the irregularity of the ECTI classified 81.1% of the images in the original groups (treated or control). Fractal analysis is capable of detecting subtle architectural changes in the oral epithelium of the rat occurring after exposure to the carcinogen, even when full malignant transformation has not yet taken place. Fractal analysis, which may prove useful for monitoring the progression of carcinogenesis in this animal model, is a morphometrical parameter in the diagnosis of oral epithelial dysplasia.

  19. Connective tissue growth factor activates pluripotency genes and mesenchymal-epithelial transition in head and neck cancer cells.

    PubMed

    Chang, Cheng-Chi; Hsu, Wen-Hao; Wang, Chen-Chien; Chou, Chun-Hung; Kuo, Mark Yen-Ping; Lin, Been-Ren; Chen, Szu-Ta; Tai, Shyh-Kuan; Kuo, Min-Liang; Yang, Muh-Hwa

    2013-07-01

    The epithelial-mesenchymal transition (EMT) is a key mechanism in both embryonic development and cancer metastasis. The EMT introduces stem-like properties to cancer cells. However, during somatic cell reprogramming, mesenchymal-epithelial transition (MET), the reverse process of EMT, is a crucial step toward pluripotency. Connective tissue growth factor (CTGF) is a multifunctional secreted protein that acts as either an oncoprotein or a tumor suppressor among different cancers. Here, we show that in head and neck squamous cell carcinoma (HNSCC), CTGF promotes the MET and reduces invasiveness. Moreover, we found that CTGF enhances the stem-like properties of HNSCC cells and increases the expression of multiple pluripotency genes. Mechanistic studies showed that CTGF induces c-Jun expression through αvβ3 integrin and that c-Jun directly activates the transcription of the pluripotency genes NANOG, SOX2, and POU5F1. Knockdown of CTGF in TW2.6 cells was shown to reduce tumor formation and attenuate E-cadherin expression in xenotransplanted tumors. In HNSCC patient samples, CTGF expression was positively correlated with the levels of CDH1, NANOG, SOX2, and POU5F1. Coexpression of CTGF and the pluripotency genes was found to be associated with a worse prognosis. These findings are valuable in elucidating the interplay between epithelial plasticity and stem-like properties during cancer progression and provide useful information for developing a novel classification system and therapeutic strategies for HNSCC.

  20. Qualitative assessment of connective tissue graft with epithelial component. A microsurgical periodontal plastic surgical technique for soft tissue esthetics.

    PubMed

    Rossi, Roberto; Pilloni, Andrea; Morales, Regina Santos

    2009-01-01

    Connective tissue grafts have been used successfully in the treatment of gingival recession. In the mid 80s and late 90s, the periodontal literature presented various techniques such as free gingival grafts, pedicle flaps, subepithelial connective tissue grafts, acellular dermal matrix grafts, and guided tissue regeneration to cover denuded root surfaces. Currently, connective tissue grafting is a reliable treatment for esthetic root coverage. This paper presents a qualitative assessment of a surgical technique that uses a connective tissue graft, including a portion of epithelium in the shape of the defect. This procedure enhances the healing of the covered root surface, increases the thickness of the soft tissue and improves esthetics. The criteria used for evaluation were: color, volume, texture, and blending. This evaluation demonstrated encouraging results from an esthetic viewpoint.

  1. Formation of adherens junctions leads to the emergence of a tissue-level tension in epithelial monolayers

    PubMed Central

    Harris, Andrew R.; Daeden, Alicia; Charras, Guillaume T.

    2014-01-01

    ABSTRACT Adherens junctions and desmosomes integrate the cytoskeletons of adjacent cells into a mechanical syncitium. In doing so, intercellular junctions endow tissues with the strength needed to withstand the mechanical stresses encountered in normal physiology and to coordinate tension during morphogenesis. Though much is known about the biological mechanisms underlying junction formation, little is known about how tissue-scale mechanical properties are established. Here, we use deep atomic force microscopy (AFM) indentation to measure the apparent stiffness of epithelial monolayers reforming from dissociated cells and examine which cellular processes give rise to tissue-scale mechanics. We show that the formation of intercellular junctions coincided with an increase in the apparent stiffness of reforming monolayers that reflected the generation of a tissue-level tension. Tension rapidly increased, reaching a maximum after 150 min, before settling to a lower level over the next 3 h as monolayers established homeostasis. The emergence of tissue tension correlated with the formation of adherens junctions but not desmosomes. As a consequence, inhibition of any of the molecular mechanisms participating in adherens junction initiation, remodelling and maturation significantly impeded the emergence of tissue-level tension in monolayers. PMID:24659804

  2. Spexin peptide is expressed in human endocrine and epithelial tissues and reduced after glucose load in type 2 diabetes.

    PubMed

    Gu, Liping; Ma, Yuhang; Gu, Mingyu; Zhang, Ying; Yan, Shuai; Li, Na; Wang, Yufan; Ding, Xiaoying; Yin, Jiajing; Fan, Nengguang; Peng, Yongde

    2015-09-01

    Spexin mRNA and protein are widely expressed in rat tissues and associate with weight loss in rodents of diet-induced obesity. Its location in endocrine and epithelial cells has also been suggested. Spexin is a novel peptide that involves weight loss in rodents of diet-induced obesity. Therefore, we aimed to examine its expression in human tissues and test whether spexin could have a role in glucose and lipid metabolism in type 2 diabetes mellitus (T2DM). The expression of the spexin gene and immunoreactivity in the adrenal gland, skin, stomach, small intestine, liver, thyroid, pancreatic islets, visceral fat, lung, colon, and kidney was higher than that in the muscle and connective tissue. Immunoreactive serum spexin levels were reduced in T2DM patients and correlated with fasting blood glucose (FBG, r=-0.686, P<0.001), hemoglobin A1c (HbA1c, r=-0.632, P<0.001), triglyceride (TG, r=-0.236, P<0.001) and low density lipoprotein-cholesterol (LDL-C, r=-0.382, P<0.001). A negative correlation of blood glucose with spexin was observed during oral glucose tolerance test (OGTT). Spexin is intensely expressed in normal human endocrine and epithelial tissues, indicating that spexin may be involved in physiological functions of endocrine and in several other tissues. Circulating spexin levels are low in T2DM patients and negatively related to blood glucose and lipids suggesting that the peptide may play a role in glucose and lipid metabolism in T2DM.

  3. [Expression and clinical significance of Pin1 and Cyclin D1 in cervical cancer cell lines and cervical epithelial tissues].

    PubMed

    Li, Hong-Yu; Xu, Qian; Zhu, Tao; Zhou, Jin-Hua; Deng, Dong-Rui; Wang, Shi-Xuan; Lu, Yun-Ping; Ma, Ding

    2006-03-01

    Peptidyl-prolyl cis/trans isomerase Pin1 is prevalently overexpressed in human cancers. Up-regulation of Pin1 elevates the expression of Cyclin D1, and plays an important role in tumorigenesis and tumor progression. This study was to investigate the expression and clinical significance of Pin1 and Cyclin D1 in cervical cancer cell lines and cervical epithelial tissues. The expression of Pin1 and Cyclin D1 in cervical cancer cell lines HeLa, SiHa, C33a and Caski were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Their expression in 88 samples of cervical tissues, including 10 samples of normal cervix, 21 samples of cervical intraepithelial neoplasia (CIN), and 57 samples of invasive cervical cancer, were detected by immunohistochemistry. The mRNA and protein levels of Pin1 were significantly higher in HeLa, SiHa, C33a, and Caski cells than in normal cervical epithelial tissues (P<0.05). The expression of Pin1 increased progressively along with the disease process from normal cervix to CIN, and to invasive cervical cancer (0%, 47.62%, 64.91%, P<0.05). Pin1 expression had no relation to disease stage (FIGO), pathologic grade, and pelvic lymph node metastasis status (P>0.05). The positive rate of Pin1 was significantly higher in cervical adenocarcinoma than in cervical squamous cell carcinoma (100% vs. 60.0%, P<0.05). In cervical cancer tissues, the overexpression of Pin1 was positively correlated to that of Cyclin D1 (P<0.05). Pin1 is overexpressed in HeLa, SiHa, C33a and Caski cell lines as well as in cervical cancer tissues. The overexpression of Pin1 is closely related to Cyclin D1 expression in cervical cancer. The aberrant expression of Pin1 and Cyclin D1 might contribute to tumorigenesis of cervical cancer.

  4. Fungal endophytes of aquatic macrophytes: diverse host-generalists characterized by tissue preferences and geographic structure

    PubMed Central

    Sandberg, Dustin C.; Battista, Lorna J.; Arnold, A. Elizabeth

    2014-01-01

    Most studies of endophytic symbionts have focused on terrestrial plants, neglecting the ecologically and economically important plants present in aquatic ecosystems. We evaluated the diversity, composition, host- and tissue affiliations, and geographic structure of fungal endophytes associated with common aquatic plants in northern Arizona, USA. Endophytes were isolated in culture from roots and photosynthetic tissues during two growing seasons. A total of 226 isolates representing 60 putative species was recovered from 9,600 plant tissue segments. Although isolation frequency was low, endophytes were phylogenetically diverse and species-rich. Comparisons among the most thoroughly sampled species and reservoirs revealed that isolation frequency and diversity did not differ significantly between collection periods, among species, among reservoirs, or as a function of depth. However, community structure differed significantly among reservoirs and tissue types. Phylogenetic analyses of a focal genus (Penicillium) corroborated estimates of species boundaries and informed community analyses, highlighting clade- and genotype-level affiliations of aquatic endophytes with both sediment- and waterborne fungi, and endophytes of proximate terrestrial plants. Together these analyses provide a first quantitative examination of endophytic associations in roots and foliage of aquatic plants and can be used to optimize survey strategies for efficiently capturing fungal biodiversity at local and regional scales. PMID:24402358

  5. Fungal endophytes of aquatic macrophytes: diverse host-generalists characterized by tissue preferences and geographic structure.

    PubMed

    Sandberg, Dustin C; Battista, Lorna J; Arnold, A Elizabeth

    2014-05-01

    Most studies of endophytic symbionts have focused on terrestrial plants, neglecting the ecologically and economically important plants present in aquatic ecosystems. We evaluated the diversity, composition, host and tissue affiliations, and geographic structure of fungal endophytes associated with common aquatic plants in lentic waters in northern Arizona, USA. Endophytes were isolated in culture from roots and photosynthetic tissues during two growing seasons. A total of 226 isolates representing 60 putative species was recovered from 9,600 plant tissue segments. Although isolation frequency was low, endophytes were phylogenetically diverse and species-rich. Comparisons among the most thoroughly sampled species and reservoirs revealed that isolation frequency and diversity did not differ significantly between collection periods, among species, among reservoirs, or as a function of depth. However, community structure differed significantly among reservoirs and tissue types. Phylogenetic analyses of a focal genus (Penicillium) corroborated estimates of species boundaries and informed community analyses, highlighting clade- and genotype-level affiliations of aquatic endophytes with both sediment- and waterborne fungi, and endophytes of proximate terrestrial plants. Together these analyses provide a first quantitative examination of endophytic associations in roots and foliage of aquatic plants and can be used to optimize survey strategies for efficiently capturing fungal biodiversity at local and regional scales.

  6. Cell-extrinsic consequences of epithelial stress: activation of protumorigenic tissue phenotypes

    PubMed Central

    2012-01-01

    Introduction Tumors are characterized by alterations in the epithelial and stromal compartments, which both contribute to tumor promotion. However, where, when, and how the tumor stroma develops is still poorly understood. We previously demonstrated that DNA damage or telomere malfunction induces an activin A-dependent epithelial stress response that activates cell-intrinsic and cell-extrinsic consequences in mortal, nontumorigenic human mammary epithelial cells (HMECs and vHMECs). Here we show that this epithelial stress response also induces protumorigenic phenotypes in neighboring primary fibroblasts, recapitulating many of the characteristics associated with formation of the tumor stroma (for example, desmoplasia). Methods The contribution of extrinsic and intrinsic DNA damage to acquisition of desmoplastic phenotypes was investigated in primary human mammary fibroblasts (HMFs) co-cultured with vHMECs with telomere malfunction (TRF2-vHMEC) or in HMFs directly treated with DNA-damaging agents, respectively. Fibroblast reprogramming was assessed by monitoring increases in levels of selected protumorigenic molecules with quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and immunocytochemistry. Dependence of the induced phenotypes on activin A was evaluated by addition of exogenous activin A or activin A silencing. In vitro findings were validated in vivo, in preinvasive ductal carcinoma in situ (DCIS) lesions by using immunohistochemistry and telomere-specific fluorescent in situ hybridization. Results HMFs either cocultured with TRF2-vHMEC or directly exposed to exogenous activin A or PGE2 show increased expression of cytokines and growth factors, deposition of extracellular matrix (ECM) proteins, and a shift toward aerobic glycolysis. In turn, these "activated" fibroblasts secrete factors that promote epithelial cell motility. Interestingly, cell-intrinsic DNA damage in HMFs induces some, but not all, of the molecules induced as a

  7. Cell-extrinsic consequences of epithelial stress: activation of protumorigenic tissue phenotypes.

    PubMed

    Fordyce, Colleen A; Patten, Kelley T; Fessenden, Tim B; DeFilippis, RosaAnna; Hwang, E Shelley; Zhao, Jianxin; Tlsty, Thea D

    2012-12-07

    Tumors are characterized by alterations in the epithelial and stromal compartments, which both contribute to tumor promotion. However, where, when, and how the tumor stroma develops is still poorly understood. We previously demonstrated that DNA damage or telomere malfunction induces an activin A-dependent epithelial stress response that activates cell-intrinsic and cell-extrinsic consequences in mortal, nontumorigenic human mammary epithelial cells (HMECs and vHMECs). Here we show that this epithelial stress response also induces protumorigenic phenotypes in neighboring primary fibroblasts, recapitulating many of the characteristics associated with formation of the tumor stroma (for example, desmoplasia). The contribution of extrinsic and intrinsic DNA damage to acquisition of desmoplastic phenotypes was investigated in primary human mammary fibroblasts (HMFs) co-cultured with vHMECs with telomere malfunction (TRF2-vHMEC) or in HMFs directly treated with DNA-damaging agents, respectively. Fibroblast reprogramming was assessed by monitoring increases in levels of selected protumorigenic molecules with quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and immunocytochemistry. Dependence of the induced phenotypes on activin A was evaluated by addition of exogenous activin A or activin A silencing. In vitro findings were validated in vivo, in preinvasive ductal carcinoma in situ (DCIS) lesions by using immunohistochemistry and telomere-specific fluorescent in situ hybridization. HMFs either cocultured with TRF2-vHMEC or directly exposed to exogenous activin A or PGE2 show increased expression of cytokines and growth factors, deposition of extracellular matrix (ECM) proteins, and a shift toward aerobic glycolysis. In turn, these "activated" fibroblasts secrete factors that promote epithelial cell motility. Interestingly, cell-intrinsic DNA damage in HMFs induces some, but not all, of the molecules induced as a consequence of cell-extrinsic DNA

  8. Increased COX-2 expression in epithelial and stromal cells of high mammographic density tissues and in a xenograft model of mammographic density.

    PubMed

    Chew, G L; Huo, C W; Huang, D; Hill, P; Cawson, J; Frazer, H; Hopper, J L; Haviv, I; Henderson, M A; Britt, K; Thompson, E W

    2015-08-01

    Mammographic density (MD) adjusted for age and body mass index is one of the strongest known risk factors for breast cancer. Given the high attributable risk of MD for breast cancer, chemoprevention with a safe and available agent that reduces MD and breast cancer risk would be beneficial. Cox-2 has been implicated in MD-related breast cancer risk, and was increased in stromal cells in high MD tissues in one study. Our study assessed differential Cox-2 expression in epithelial and stromal cells in paired samples of high and low MD human breast tissue, and in a validated xenograft biochamber model of MD. We also examined the effects of endocrine treatment upon Cox-2 expression in high and low MD tissues in the MD xenograft model. Paired high and low MD human breast tissue samples were immunostained for Cox-2, then assessed for differential expression and staining intensity in epithelial and stromal cells. High and low MD human breast tissues were separately maintained in biochambers in mice treated with Tamoxifen, oestrogen or placebo implants, then assessed for percentage Cox-2 staining in epithelial and stromal cells. Percentage Cox-2 staining was greater for both epithelial (p = 0.01) and stromal cells (p < 0.0001) of high compared with low MD breast tissues. In high MD biochamber tissues, percentage Cox-2 staining was greater in stromal cells of oestrogen-treated versus placebo-treated tissues (p = 0.05).

  9. Structural centrosome aberrations favor proliferation by abrogating microtubule-dependent tissue integrity of breast epithelial mammospheres

    PubMed Central

    Schnerch, D; Nigg, E A

    2016-01-01

    Structural centrosome aberrations are frequently observed in early stage carcinomas, but their role in malignant transformation is poorly understood. Here, we examined the impact of overexpression of Ninein-like protein (Nlp) on the architecture of polarized epithelia in three-dimensional mammospheres. When Nlp was overexpressed to levels resembling those seen in human tumors, it formed striking centrosome-related bodies (CRBs), which sequestered Ninein and affected the kinetics of microtubule (MT) nucleation and release. In turn, the profound reorganization of the MT cytoskeleton resulted in mislocalization of several adhesion and junction proteins as well as the tumor suppressor Scribble, resulting in the disruption of epithelial polarity, cell-cell interactions and mammosphere architecture. Remarkably, cells harboring Nlp-CRBs displayed an enhanced proliferative response to epidermal growth factor. These results demonstrate that structural centrosome aberrations cause not only the disruption of epithelial polarity but also favor overproliferation, two phenotypes typically associated with human carcinomas. PMID:26364601

  10. All hands on DE(T)C: Epithelial-resident γδ T cells respond to tissue injury

    PubMed Central

    Ramirez, Kevin; Witherden, Deborah A.; Havran, Wendy L.

    2015-01-01

    Immunology has traditionally focused on the lymphocytes circulating among primary lymphoid organs while the large reservoir of tissue-resident T cells have received relatively less attention. In epithelia, these populations are comprised of significant, and sometimes exclusive, subsets of γδ T cells that are highly specialized in promoting tissue homeostasis. As the epithelial layers of the skin and gut are permanently exposed to the environment, they are continually subject to injury and therefore require highly efficient repair processes to maintain barrier functions. Here, we review the role of γδ T cells in promoting wound healing, a critical and complex process occurring in the skin and other barrier sites. PMID:25958272

  11. Metabolic substrate utilization by tumour and host tissues in cancer cachexia.

    PubMed Central

    Mulligan, H D; Tisdale, M J

    1991-01-01

    Utilization of metabolic substrates in tumour and host tissues was determined in the presence or absence of two colonic tumours, the MAC16, which is capable of inducing cachexia in recipient animals, and the MAC13, which is of the same histological type, but without the effect on host body composition. Glucose utilization by different tissues was determined in vivo by the 2-deoxyglucose tracer technique. Glucose utilization by the MAC13 tumour was significantly higher than by the MAC16 tumour, and in animals bearing tumours of either type the tumour was the second major consumer of glucose after the brain. This extra demand for glucose was accompanied by a marked decrease in glucose utilization by the epididymal fat-pads, testes, colon, spleen, kidney and, in particular, the brain, in tumour-bearing animals irrespective of cachexia. The decrease in glucose consumption by the brain was at least as high as the metabolic demand by the tumour. This suggests that the tissues of tumour-bearing animals adapt to use substrates other than glucose and that alterations in glucose utilization are not responsible for the cachexia. Studies in vitro showed that brain metabolism in the tumour-bearing state was maintained by an increased use of lactate and 3-hydroxybutyrate, accompanied by a 50% increase in 3-oxoacid CoA-transferase. This was supported by studies in vivo which showed an increased metabolism of 3-hydroxybutyrate in tumour-bearing animals. Thus ketone bodies may be utilized as a metabolic fuel during the cancer-bearing state, even though the nutritional conditions mimic the fed state. PMID:1859359

  12. Opposite polarity of virus budding and of viral envelope glycoprotein distribution in epithelial cells derived from different tissues

    PubMed Central

    1992-01-01

    We compared the surface envelope glycoprotein distribution and the budding polarity of four RNA viruses in Fischer rat thyroid (FRT) cells and in CaCo-2 cells derived from a human colon carcinoma. Whereas both FRT and CaCo-2 cells sort similarly influenza hemagglutinin and vesicular stomatitis virus (VSV) G protein, respectively, to apical and basolateral membrane domains, they differ in their handling of two togaviruses, Sindbis and Semliki Forest virus (SFV). By conventional EM Sindbis virus and SFV were shown to bud apically in FRT cells and basolaterally in CaCo-2 cells. Consistent with this finding, the distribution of the p62/E2 envelope glycoprotein of SFV, assayed by immunoelectronmicroscopy and by domain-selective surface biotinylation was predominantly apical on FRT cells and basolateral on CaCo-2 cells. We conclude that a given virus and its envelope glycoprotein can be delivered to opposite membrane domains in epithelial cells derived from different tissues. The tissue specificity in the polarity of virus budding and viral envelope glycoprotein distribution indicate that the sorting machinery varies considerably between different epithelial cell types. PMID:1572895

  13. YAP and TAZ in epithelial stem cells: A sensor for cell polarity, mechanical forces and tissue damage

    PubMed Central

    Elbediwy, Ahmed; Vincent‐Mistiaen, Zoé I.

    2016-01-01

    The YAP/TAZ family of transcriptional co‐activators drives cell proliferation in epithelial tissues and cancers. Yet, how YAP and TAZ are physiologically regulated remains unclear. Here we review recent reports that YAP and TAZ act primarily as sensors of epithelial cell polarity, being inhibited when cells differentiate an apical membrane domain, and being activated when cells contact the extracellular matrix via their basal membrane domain. Apical signalling occurs via the canonical Crumbs/CRB‐Hippo/MST‐Warts/LATS kinase cascade to phosphorylate and inhibit YAP/TAZ. Basal signalling occurs via Integrins and Src family kinases to phosphorylate and activate YAP/TAZ. Thus, YAP/TAZ is localised to the nucleus in basal stem/progenitor cells and cytoplasm in differentiated squamous cells or columnar cells. In addition, other signals such as mechanical forces, tissue damage and possibly receptor tyrosine kinases (RTKs) can influence MST‐LATS or Src family kinase activity to modulate YAP/TAZ activity. PMID:27173018

  14. Simultaneous assessment of the pharmacokinetics of a pleuromutilin, lefamulin, in plasma, soft tissues and pulmonary epithelial lining fluid.

    PubMed

    Zeitlinger, M; Schwameis, R; Burian, A; Burian, B; Matzneller, P; Müller, M; Wicha, W W; Strickmann, D B; Prince, W

    2016-04-01

    Lefamulin is a pleuromutilin antibiotic under evaluation for the treatment of bacterial infections, including respiratory tract infections. Currently, there are no high-quality pharmacokinetic data on drug tissue concentrations of lefamulin available. A single dose of intravenous lefamulin (150 mg) was given to 12 healthy men. The registered EudraCT number for this study was 2010-021938-54. Lefamulin concentrations were simultaneously measured in plasma, skeletal muscle tissue, subcutaneous adipose tissue and epithelial lining fluid (ELF) over 24 h, and corresponding pharmacokinetic parameters were calculated. Microdialysis was used to measure unbound lefamulin concentrations in skeletal muscle tissue and subcutaneous adipose tissue, which were similar to unbound lefamulin concentrations in plasma. Bronchoalveolar lavage was performed 1, 2, 4 and 8 h post-dose to determine lefamulin concentrations in ELF. Unbound lefamulin levels showed a 5.7-fold higher exposure in ELF compared with that in plasma, demonstrating good penetration to the target site. Lefamulin may be an addition to the therapeutic armamentarium for the treatment of infections. Simultaneous measurements of unbound drug concentration can guide target attainment for future therapeutic trials. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. Epithelial Intermediate Filaments: Guardians against Microbial Infection?

    PubMed Central

    Geisler, Florian; Leube, Rudolf E.

    2016-01-01

    Intermediate filaments are abundant cytoskeletal components of epithelial tissues. They have been implicated in overall stress protection. A hitherto poorly investigated area of research is the function of intermediate filaments as a barrier to microbial infection. This review summarizes the accumulating knowledge about this interaction. It first emphasizes the unique spatial organization of the keratin intermediate filament cytoskeleton in different epithelial tissues to protect the organism against microbial insults. We then present examples of direct interaction between viral, bacterial, and parasitic proteins and the intermediate filament system and describe how this affects the microbe-host interaction by modulating the epithelial cytoskeleton, the progression of infection, and host response. These observations not only provide novel insights into the dynamics and function of intermediate filaments but also indicate future avenues to combat microbial infection. PMID:27355965

  16. Clinical Implications of Oral Candidiasis: Host Tissue Damage and Disseminated Bacterial Disease

    PubMed Central

    Kong, Eric F.; Kucharíková, Sona; Peters, Brian M.; Shirtliff, Mark E.

    2014-01-01

    The clinical significance of polymicrobial interactions, particularly those between commensal species with high pathogenic potential, remains largely understudied. Although the dimorphic fungal species Candida albicans and the bacterium Staphylococcus aureus are common cocolonizers of humans, they are considered leading opportunistic pathogens. Oral candidiasis specifically, characterized by hyphal invasion of oral mucosal tissue, is the most common opportunistic infection in HIV+ and immunocompromised individuals. In this study, building on our previous findings, a mouse model was developed to investigate whether the onset of oral candidiasis predisposes the host to secondary staphylococcal infection. The findings demonstrated that in mice with oral candidiasis, subsequent exposure to S. aureus resulted in systemic bacterial infection with high morbidity and mortality. Histopathology and scanning electron microscopy of tongue tissue from moribund animals revealed massive C. albicans hyphal invasion coupled with S. aureus deep tissue infiltration. The crucial role of hyphae in the process was demonstrated using a non-hypha-producing and a noninvasive hypha-producing mutant strains of C. albicans. Further, in contrast to previous findings, S. aureus dissemination was aided but not contingent upon the presence of the Als3p hypha-specific adhesion. Importantly, impeding development of mucosal C. albicans infection by administering antifungal fluconazole therapy protected the animals from systemic bacterial disease. The combined findings from this study demonstrate that oral candidiasis may constitute a risk factor for disseminated bacterial disease warranting awareness in terms of therapeutic management of immunocompromised individuals. PMID:25422264

  17. Clinical implications of oral candidiasis: host tissue damage and disseminated bacterial disease.

    PubMed

    Kong, Eric F; Kucharíková, Sona; Van Dijck, Patrick; Peters, Brian M; Shirtliff, Mark E; Jabra-Rizk, Mary Ann

    2015-02-01

    The clinical significance of polymicrobial interactions, particularly those between commensal species with high pathogenic potential, remains largely understudied. Although the dimorphic fungal species Candida albicans and the bacterium Staphylococcus aureus are common cocolonizers of humans, they are considered leading opportunistic pathogens. Oral candidiasis specifically, characterized by hyphal invasion of oral mucosal tissue, is the most common opportunistic infection in HIV(+) and immunocompromised individuals. In this study, building on our previous findings, a mouse model was developed to investigate whether the onset of oral candidiasis predisposes the host to secondary staphylococcal infection. The findings demonstrated that in mice with oral candidiasis, subsequent exposure to S. aureus resulted in systemic bacterial infection with high morbidity and mortality. Histopathology and scanning electron microscopy of tongue tissue from moribund animals revealed massive C. albicans hyphal invasion coupled with S. aureus deep tissue infiltration. The crucial role of hyphae in the process was demonstrated using a non-hypha-producing and a noninvasive hypha-producing mutant strains of C. albicans. Further, in contrast to previous findings, S. aureus dissemination was aided but not contingent upon the presence of the Als3p hypha-specific adhesion. Importantly, impeding development of mucosal C. albicans infection by administering antifungal fluconazole therapy protected the animals from systemic bacterial disease. The combined findings from this study demonstrate that oral candidiasis may constitute a risk factor for disseminated bacterial disease warranting awareness in terms of therapeutic management of immunocompromised individuals.

  18. Transplantation of Donor-Origin Mouse Embryonic Stem Cell-Derived Thymic Epithelial Progenitors Prevents the Development of Chronic Graft-versus-Host Disease in Mice.

    PubMed

    Hu, Rong; Liu, Yalan; Su, Min; Song, Yinhong; Rood, Debra; Lai, Laijun

    2017-01-01

    Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy for many malignant and nonmalignant diseases. However, chronic graft-versus-host disease (cGVHD) remains a significant cause of late morbidity and mortality after allogeneic HSCT. cGVHD often manifests as autoimmune syndrome. Thymic epithelial cells (TECs) play a critical role in supporting negative selection and regulatory T-cell (Treg) generation. Studies have shown that damage in TECs is sufficient to induce cGVHD. We have previously reported that mouse embryonic stem cells (mESCs) can be selectively induced to generate thymic epithelial progenitors (TEPs) in vitro. When transplanted in vivo, mESC-TEPs further develop into TECs that support T-cell development. We show here that transplantation of donor-origin mESC-TEPs into cGVHD recipients induces immune tolerance to both donor and host antigens and prevents the development of cGVHD. This is associated with more TECs and Tregs. Our results suggest that embryonic stem cell-derived TEPs may offer a new tool to control cGVHD. Stem Cells Translational Medicine 2017;6:121-130.

  19. Transplantation of Donor-Origin Mouse Embryonic Stem Cell-Derived Thymic Epithelial Progenitors Prevents the Development of Chronic Graft-Versus-Host Disease in Mice.

    PubMed

    Hu, Rong; Liu, Yalan; Su, Min; Song, Yinhong; Rood, Debra; Lai, Laijun

    2016-08-02

    : Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy for many malignant and nonmalignant diseases. However, chronic graft-versus-host disease (cGVHD) remains a significant cause of late morbidity and mortality after allogeneic HSCT. cGVHD often manifests as autoimmune syndrome. Thymic epithelial cells (TECs) play a critical role in supporting negative selection and regulatory T-cell (Treg) generation. Studies have shown that damage in TECs is sufficient to induce cGVHD. We have previously reported that mouse embryonic stem cells (mESCs) can be selectively induced to generate thymic epithelial progenitors (TEPs) in vitro. When transplanted in vivo, mESC-TEPs further develop into TECs that support T-cell development. We show here that transplantation of donor-origin mESC-TEPs into cGVHD recipients induces immune tolerance to both donor and host antigens and prevents the development of cGVHD. This is associated with more TECs and Tregs. Our results suggest that embryonic stem cell-derived TEPs may offer a new tool to control cGVHD.

  20. Isolates of citrus exocortis viroid recovered by host and tissue selection.

    PubMed

    Semancik, J S; Szychowski, J A; Rakowski, A G; Symons, R H

    1993-11-01

    Isolates of citrus exocortis viroid (CEV) from a single sweet orange citrus source have been selected by sequential passage through the alternative hosts citron, Gynura aurantiaca, a hybrid tomato Lycopersicon esculentum x L. peruvianum, and from disorganized callus culture of the hybrid tomato. The distinctions in symptom expression, titre and electrophoretic mobility among the CEV isolates, operationally termed CEVc (citron), CEVg (Gynura), CEVt (tomato) and CEVcls (callus) are supported by characteristically different nucleotide sequences. The nucleotide sequence of full-length cDNA clones of CEVc purified from citron shows exchanges not reported for any previously described CEV variant. An unusual number of exchanges have been localized in the terminal domains of all the isolates analysed here. A common pattern of nucleotide exchanges, described as a 'tomato signature', can be detected in all of the isolates derived from hybrid tomato tissues.

  1. Effect of host plant tissue on the vector transmission of grapevine leafroll-associated virus 3.

    PubMed

    Tsai, Chi-Wei; Bosco, Domenico; Daane, Kent M; Almeida, Rodrigo P P

    2011-10-01

    Many biotic and abiotic factors affect the transmission efficiency of vector-borne plant pathogens. Insect vector within-plant distribution and host tissue preference are known to affect pathogen acquisition and inoculation rates. In this study, we first investigated whether feeding tissue affects the transmission of Grapevine leafroll-associated virus 3 by Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) and the effect of mealybug within-plant distribution on virus transmission under greenhouse conditions. Results showed no significant effect on transmission efficiency after insect confinement on leaf blades, petioles or stems of virus source or healthy test plants for either acquisition or inoculation trials. Transmission efficiency of a single mealybug varied from 4 to 25% in those trials. Second, we tested whether leaf position affected transmission efficiency due to potentially variable virus populations within acquisition plant tissues. No significant differences of transmission rate among acquisition leaf position were observed, probably because there were no differences in the virus population within source tissues. Finally, we examined the seasonality of the virus in field-collected samples and found that GLRaV-3 prevalence varied along a growing season, such that GLRaV-3 translocated along expanding shoots to leaves. Similarly, mealybug populations are known to increase in spring, and then mealybugs spread to cordons and leaves. This coordination of spatial and temporal dynamics of the virus and its vector may increase the risk of GLRaV-3 transmission during late spring and early summer. Further integration of information about pathogen populations in plants, vector feeding behavior and vector population seasonality could lead to more effective management practices.

  2. Endogenous two-photon fluorescence imaging elucidates metabolic changes related to enhanced glycolysis and glutamine consumption in precancerous epithelial tissues.

    PubMed

    Varone, Antonio; Xylas, Joanna; Quinn, Kyle P; Pouli, Dimitra; Sridharan, Gautham; McLaughlin-Drubin, Margaret E; Alonzo, Carlo; Lee, Kyongbum; Münger, Karl; Georgakoudi, Irene

    2014-06-01

    Alterations in the balance between different metabolic pathways used to meet cellular bioenergetic and biosynthetic demands are considered hallmarks of cancer. Optical imaging relying on endogenous fluorescence has been used as a noninvasive approach to assess tissue metabolic changes during cancer development. However, quantitative correlations of optical assessments with variations in the concentration of relevant metabolites or in the specific metabolic pathways that are involved have been lacking. In this study, we use high-resolution, depth-resolved imaging, relying entirely on endogenous two-photon excited fluorescence in combination with invasive biochemical assays and mass spectrometry to demonstrate the sensitivity and quantitative nature of optical redox ratio tissue assessments. We identify significant differences in the optical redox ratio of live, engineered normal and precancerous squamous epithelial tissues. We establish that while decreases in the optical redox ratio are associated with enhanced levels of glycolysis relative to oxidative phosphorylation, increases in glutamine consumption to support energy production are associated with increased optical redox ratio values. Such mechanistic insights in the origins of optical metabolic assessments are critical for exploiting fully the potential of such noninvasive approaches to monitor and understand important metabolic changes that occur in live tissues at the onset of cancer or in response to treatment.

  3. Genome degradation in Brucella ovis corresponds with narrowing of its host range and tissue tropism.

    PubMed

    Tsolis, Renee M; Seshadri, Rekha; Santos, Renato L; Sangari, Felix J; Lobo, Juan M García; de Jong, Maarten F; Ren, Qinghu; Myers, Garry; Brinkac, Lauren M; Nelson, William C; Deboy, Robert T; Angiuoli, Samuel; Khouri, Hoda; Dimitrov, George; Robinson, Jeffrey R; Mulligan, Stephanie; Walker, Richard L; Elzer, Philip E; Hassan, Karl A; Paulsen, Ian T

    2009-01-01

    Brucella ovis is a veterinary pathogen associated with epididymitis in sheep. Despite its genetic similarity to the zoonotic pathogens B. abortus, B. melitensis and B. suis, B. ovis does not cause zoonotic disease. Genomic analysis of the type strain ATCC25840 revealed a high percentage of pseudogenes and increased numbers of transposable elements compared to the zoonotic Brucella species, suggesting that genome degradation has occurred concomitant with narrowing of the host range of B. ovis. The absence of genomic island 2, encoding functions required for lipopolysaccharide biosynthesis, as well as inactivation of genes encoding urease, nutrient uptake and utilization, and outer membrane proteins may be factors contributing to the avirulence of B. ovis for humans. A 26.5 kb region of B. ovis ATCC25840 Chromosome II was absent from all the sequenced human pathogenic Brucella genomes, but was present in all of 17 B. ovis isolates tested and in three B. ceti isolates, suggesting that this DNA region may be of use for differentiating B. ovis from other Brucella spp. This is the first genomic analysis of a non-zoonotic Brucella species. The results suggest that inactivation of genes involved in nutrient acquisition and utilization, cell envelope structure and urease may have played a role in narrowing of the tissue tropism and host range of B. ovis.

  4. Genome Degradation in Brucella ovis Corresponds with Narrowing of Its Host Range and Tissue Tropism

    PubMed Central

    Tsolis, Renee M.; Seshadri, Rekha; Santos, Renato L.; Sangari, Felix J.; Lobo, Juan M. García; de Jong, Maarten F.; Ren, Qinghu; Myers, Garry; Brinkac, Lauren M.; Nelson, William C.; DeBoy, Robert T.; Angiuoli, Samuel; Khouri, Hoda; Dimitrov, George; Robinson, Jeffrey R.; Mulligan, Stephanie; Walker, Richard L.; Elzer, Philip E.; Hassan, Karl A.; Paulsen, Ian T.

    2009-01-01

    Brucella ovis is a veterinary pathogen associated with epididymitis in sheep. Despite its genetic similarity to the zoonotic pathogens B. abortus, B. melitensis and B. suis, B. ovis does not cause zoonotic disease. Genomic analysis of the type strain ATCC25840 revealed a high percentage of pseudogenes and increased numbers of transposable elements compared to the zoonotic Brucella species, suggesting that genome degradation has occurred concomitant with narrowing of the host range of B. ovis. The absence of genomic island 2, encoding functions required for lipopolysaccharide biosynthesis, as well as inactivation of genes encoding urease, nutrient uptake and utilization, and outer membrane proteins may be factors contributing to the avirulence of B. ovis for humans. A 26.5 kb region of B. ovis ATCC25840 Chromosome II was absent from all the sequenced human pathogenic Brucella genomes, but was present in all of 17 B. ovis isolates tested and in three B. ceti isolates, suggesting that this DNA region may be of use for differentiating B. ovis from other Brucella spp. This is the first genomic analysis of a non-zoonotic Brucella species. The results suggest that inactivation of genes involved in nutrient acquisition and utilization, cell envelope structure and urease may have played a role in narrowing of the tissue tropism and host range of B. ovis. PMID:19436743

  5. Histopathology of a mesoparasitic hatschekiid copepod in hospite: does Mihbaicola sakamakii (Copepoda: Siphonostomatoida: Hatschekiidae) fast within the host fish tissue?

    PubMed

    Hirose, Euichi; Uyeno, Daisuke

    2014-08-01

    Mihbaicola sakamakii is a mesoparasitic copepod that infests the branchiostegal membranes of groupers (Perciformes: Serranidae). In this study, we observed M. sakamakii within host tissue. Histologically, copepods were found enclosed inside a pouch composed of the thickened epidermis of the host, tightly encased on all sides by the host epidermal pouch wall. There were no host blood cells or other food resources in the pouch lumen. Since the host epidermis was intact and continuous, even in the vicinity of the oral region of the parasite, the copepod would not have access to the host blood in this state. However, the stomach (ampullary part of the mid gut) was filled with granular components, the majority of which were crystalloids that likely originated from fish erythrocyte hemoglobin. We supposed that the parasite drinks blood exuded from the lesion in the fish caused by copepod entry into the host tissue. Invasion of the parasite may elicit immune responses in the host, but there were no traces on the copepod of any cellular immune reactions, such as encapsulation. The array of minute protuberances on the copepod cuticle surface may be involved in avoidance of cell adhesion. After the lesion has healed, the copepod is enclosed in a tough epidermal pouch, in which it gradually digests the contents of its stomach and continues egg production.

  6. Inflammatory reaction and neotissue maturation in the early host tissue incorporation of polypropylene prostheses.

    PubMed

    Pascual, G; Rodríguez, M; Sotomayor, S; Pérez-Köhler, B; Bellón, J M

    2012-12-01

    The use prosthetic materials for the surgical repair of abdominal wall defects has become almost standard practice. This study was designed to assess the expression of different growth factors (VEGF/TGF-β1) and macrophages during the early host tissue incorporation of several polypropylene lightweight (PP-LW)-including one partially absorbable-and heavyweight (PP-HW) prosthetic meshes. Ventral defects were created in the anterior abdominal wall of New Zealand rabbits and repaired by fixing PP-LW meshes of different pore size and a low porosity PP-HW mesh to the edges of the defect. Following killing 14 days after implant, specimens were taken to examine TGF-β1/VEGF gene and protein expression by qRT-PCR and immunohistochemistry. The macrophage response was also assessed. All the materials showed good host tissue incorporation, with a more severe inflammatory reaction and greater numbers of macrophages recorded in the partially absorbable LW implants. Relative amounts of VEGF mRNA were significantly lower for the LW partially absorbable implants compared with the remaining LW meshes. Protein expression of VEGF showed undetectable or minimum staining in the different groups. TGF-β1 mRNA levels were also lower in the partially absorbable group compared with one of PP-LW type of mesh. Gene expression patterns were consistent with the TGF-β1 protein levels detected. The results suggest that VEGF and TGF-β1 expression were independent of mesh pore size. The expression of both growth factors and the macrophage response were correlated with the presence of biodegradable material in the mesh. The presence of absorbable material in the LW mesh gave rise to a more intense inflammatory reaction and the reduced synthesis of growth factors known to contribute to neotissue maturation.

  7. Graft-versus-host disease reduces regulatory T-cell migration into the tumour tissue

    PubMed Central

    Dürr, Christoph; Follo, Marie; Idzko, Marco; Reichardt, Wilfried; Zeiser, Robert

    2012-01-01

    The therapeutic principle of allogeneic haematopoietic cell transplantation (allo-HCT) is based on an active donor immune system that eliminates host-derived tumour cells. We hypothesized that in addition to the alloantigen-driven anti-tumour response, disruption of the immunological microenvironment within the tumour is responsible for its elimination after allo-HCT. We observed that induction of graft-versus-host disease (GvHD) significantly reduced the abundance of luc+ FoxP3+ regulatory T (Treg) cells in the tumour tissue, which is indicative of impaired or over-ridden tumour recruitment signals towards Treg cells. Analysis of the intestines and liver revealed chemokines and purine nucleotides as candidates for attracting Treg to these sites of inflammation. Despite its expression on tissue-residing Treg cells, the chemokine receptor CCR3 was not critical for Treg-cell function following allo-HCT. Extracellular ATP can attract immune cells via P2Y2. P2Y2 was found to be expressed on Treg cells, and we found a partial reduction of GvHD prevention when P2Y2−/− rather than P2Y2+/+ Treg cells were given. Exogenous local inflammation reduced Treg-cell accumulation in the tumour, suggesting a potential clinical approach to prevent Treg-cell-mediated tumour escape. In conclusion, we demonstrate that GvHD-related inflammation reduced Treg-cell numbers at the tumour sites, which may in turn help to explain the observation that patients with GvHD have a lower risk of tumour relapse. PMID:22681312

  8. Proteomic Changes of Tissue-Tolerable Plasma Treated Airway Epithelial Cells and Their Relation to Wound Healing

    PubMed Central

    Lendeckel, Derik; Eymann, Christine; Emicke, Philipp; Daeschlein, Georg; Darm, Katrin; O'Neil, Serena; Beule, Achim G.; von Woedtke, Thomas; Völker, Uwe; Weltmann, Klaus-Dieter; Jünger, Michael; Hosemann, Werner; Scharf, Christian

    2015-01-01

    Background. The worldwide increasing number of patients suffering from nonhealing wounds requires the development of new safe strategies for wound repair. Recent studies suggest the possibility of nonthermal (cold) plasma application for the acceleration of wound closure. Methods. An in vitro wound healing model with upper airway S9 epithelial cells was established to determine the macroscopically optimal dosage of tissue-tolerable plasma (TTP) for wound regeneration, while a 2D-difference gel electrophoresis (2D-DIGE) approach was used to quantify the proteomic changes in a hypothesis-free manner and to evaluate the balance of beneficial and adverse effects due to TTP application. Results. Plasma doses from 30 s up to 360 s were tested in relation to wound closure after 24 h, 48 h, 72 h, 96 h, and 120 h, in which lower doses (30, 60, and 120 s) resulted in dose-dependent improved wound healing rate compared to untreated cells. Thereby, the 120 s dose caused significantly the best wound healing properties after 96 and 120 h. The proteome analysis combined with IPA revealed that a lot of affected stress adaptation responses are linked to oxidative stress response emphasizing oxidative stress as a possible key event in the regeneration process of epithelial cells as well as in the adaptation to plasma exposure. Further cellular and molecular functions like proliferation and apoptosis were significantly up- or downregulated by all TTP treatments but mostly by the 120 s dose. Conclusions. For the first time, we were able to show plasma effects on cellular adaptation of upper airway epithelial S9 cells improving wound healing. This is of particular interest for plasma application, for example, in the surgery field of otorhinolaryngology or internal medicine. PMID:26539504

  9. Laminin alpha1-chain shows a restricted distribution in epithelial basement membranes of fetal and adult human tissues.

    PubMed

    Virtanen, I; Gullberg, D; Rissanen, J; Kivilaakso, E; Kiviluoto, T; Laitinen, L A; Lehto, V P; Ekblom, P

    2000-06-15

    Two novel monoclonal antibodies were raised and used to study the expression of laminin (Ln) alpha1-chain in developing and adult human tissues. In both fetal and adult kidney, a distinct immunoreactivity was seen in basement membranes (BM) of most proximal tubules but not in the distal tubular or glomerular BM or in the basal laminae of blood vessels. Immunoprecipitation of metabolically labeled cultured human renal proximal tubular cells showed an abundant production and deposition of Ln alpha1-chain to the extracellular matrix, suggestive of an epithelial origin of kidney Ln-1. Quantitative cell adhesion experiments with JAR choriocarcinoma cells showed that purified human Ln-1 is a good substrate for cell adhesion that it is differently recognized by integrin receptors when compared to mouse Ln-1. In fetal and adult testes immunoreactivity was solely confined to BM of the seminiferous epithelium. In the airways BM-confined reaction was only seen in fetal budding bronchial tubules (16-19 weeks) at the pseudoglandular stage of development. In the skin a distinct immunoreactivity was confined to BM of developing hair buds but not in epithelial BMs of adult epidermis or of epidermal appendages. In other adult tissues, immunoreactivity was found in BMs of thyroid, salivary, and mammary glands as well as in BMs of endometrium and endocervix, but not of ectocervix or vagina. No immunoreactivity was found in BMs of most of the digestive tract, including the liver and pancreas, except for BMs of esophageal submucosal glands and duodenal Brunner's glands. In fetal specimens, BMs of the bottoms of the intestinal and gastric glands were positive. Basal laminae of blood vessels were generally negative for Ln alpha1 chain with the exception of specimens of both fetal and adult central nervous system in which immunoreactivity for Ln alpha1 chain was prominently confined to capillary walls. The results suggest that outside the central nervous system, Ln alpha1 chain shows a

  10. Effects of Coralliophila violacea on tissue loss in the scleractinian corals Porites spp. depend on host response

    USGS Publications Warehouse

    Raymundo, L.; Work, Thierry M.; Miller, R.L.; Lozada-Misa, P.L.

    2016-01-01

    We investigated interactions between the corallivorous gastropod Coralliophila violacea and its preferred hosts Porites spp. Our objectives were to experimentally determine whether tissue loss could progress in Porites during or after Coralliophila predation on corals with and without tissue loss and to histologically document snail predation. In 64% of feeding scars, tissue regenerated within 3 wk, leaving no trace of predation. However, in roughly 28% of scars, lesions progressed to subacute tissue loss resembling white syndrome. In feeding experiments, scars from snails previously fed diseased tissue developed progressive tissue loss twice as frequently as scars from snails previously fed healthy tissue. Scars from previously healthy-fed snails were 3 times as likely to heal as those from previously diseased-fed snails. Histology revealed marked differences in host responses to snails; P. cylindrica manifested a robust inflammatory response with fewer secondary colonizing organisms such as algae, sponges, and helminths, whereas P. rus showed no evident inflammation and more secondary colonization. We conclude that lesion progression associated with Coralliophila may be associated with secondary colonization of coral tissues damaged by predator-induced trauma and necrosis. Importantly, variation at the cellular level should be considered when explaining interspecific differences in host responses in corals impacted by phenomena such as predation.

  11. Harvesting Human Prostate Tissue Material and Culturing Primary Prostate Epithelial Cells.

    PubMed

    Frame, Fiona M; Pellacani, Davide; Collins, Anne T; Maitland, Norman J

    2016-01-01

    In order to fully explore the biology of a complex solid tumor such as prostate cancer, it is desirable to work with patient tissue. Only by working with cells from a tissue can we take into account patient variability and tumor heterogeneity. Cell lines have long been regarded as the workhorse of cancer research and it could be argued that they are of most use when considered within a panel of cell lines, thus taking into account specified mutations and variations in phenotype between different cell lines. However, often very different results are obtained when comparing cell lines to primary cells cultured from tissue. It stands to reason that cells cultured from patient tissue represents a close-to-patient model that should and does produce clinically relevant data. This chapter aims to illustrate the methods of processing, storing and culturing cells from prostate tissue, with a description of potential uses.

  12. Extracellular matrix-dependent tissue-specific gene expression in mammary epithelial cells requires both physical and biochemical signal transduction

    SciTech Connect

    Roskelley, C.D.; Desprez, P.Y.; Bissell, M.J. )

    1994-12-20

    Extracellular matrix (ECM) profoundly influences the growth and differentiation of the mammary gland epithelium, both in culture and in vivo. Utilizing a clonal population of mouse mammary epithelial cells that absolutely requires an exogenous ECM for function, we developed a rapid assay to study signal transduction by ECM. Two components of the cellular response to a basement membrane overlay that result in the expression of the milk protein [beta]-casein were defined. The first component of this response involves a rounding and clustering of the cells that can be physically mimicked by plating the cells on a nonadhesive substratum. The second component is biochemical in nature, and it is associated with [beta][sub 1] integrin clustering and increased tyrosine phosphorylation. The second component is initiated in a morphology-independent manner, but the proper translation of this biochemical signal into a functional response requires cell rounding and cell clustering. Thus, physical and biochemical signal transduction events contribute to the ECM-dependent regulation of tissue-specific gene expression in mouse mammary epithelial cells. 44 refs., 6 figs.

  13. Immunohistochemical correlation of matrix metalloproteinase-2 and tissue inhibitors of metalloproteinase-2 in tobacco associated epithelial dysplasia.

    PubMed

    Bajracharya, Dipshikha; Shrestha, Bijayatha; Kamath, Asha; Menon, Aparna; Radhakrishnan, Raghu

    2014-01-01

    To study the immunohistochemical expression of matrix metalloproteinase and tissue inhibitors of matrix metalloproteinase-2 in different histological grades of tobacco associated epithelial dysplasia and correlate the association between these proteases. Potentially malignant oral disorders (PMODs) progressing to oral cancer are related to the severity of epithelial dysplasia. A retrospective immunohistochemical study was carried out on 30 clinically and histologically proven cases of leukoplakia with dysplasia and 10 cases of normal buccal mucosa using anti-MMP-2 and anti-TIMP-2 monoclonal antibodies. Mann Whitney U test, for comparing the expression of both MMP-2 and TIMP-2 in normal mucosa with dysplasia, was highly significant (P < 0.001). Kruskal-Wallis test to compare the median score of MMP-2 and TIMP-2 in different grades of dysplasia showed statistical significance (P < 0.001), and a Spearman's correlation between MMP-2 and TIMP-2 through different grades of dysplasia and cells observed showed positive correlation. Concomitant increase in the expression of both MMP-2 and TIMP-2 suggested that the activation of MMP-2 is dependent on TIMP-2 acting as a cofactor. Changes in TIMP-2 levels are considered important because they directly affect the level of MMP-2 activity.

  14. Endogenous tissue factor pathway inhibitor has a limited effect on host defence in murine pneumococcal pneumonia.

    PubMed

    van den Boogaard, Florry E; van 't Veer, Cornelis; Roelofs, Joris J T H; Meijers, Joost C M; Schultz, Marcus J; Broze, George J; van der Poll, Tom

    2015-07-01

    Streptococcus (S.) pneumoniae is the most common causative pathogen in community-acquired pneumonia. Coagulation and inflammation interact in the host response to infection. Tissue factor pathway inhibitor (TFPI) is a natural anticoagulant protein that inhibits tissue factor (TF), the main activator of inflammation-induced coagulation. It was the objective of this study to investigate the effect of endogenous TFPI levels on coagulation, inflammation and bacterial growth during S. pneumoniae pneumonia in mice. The effect of low endogenous TFPI levels was studied by administration of a neutralising anti-TFPI antibody to wild-type mice, and by using genetically modified mice expressing low levels of TFPI, due to a genetic deletion of the first Kunitz domain of TFPI (TFPIK1(-/-)) rescued with a human TFPI transgene. Pneumonia was induced by intranasal inoculation with S. pneumoniae and samples were obtained at 6, 24 and 48 hours after infection. Anti-TFPI reduced TFPI activity by ~50 %. Homozygous lowTFPI mice and heterozygous controls had ~10 % and ~50 % of normal TFPI activity, respectively. TFPI levels did not influence bacterial growth or dissemination. Whereas lung pathology was unaffected in all groups, mice with ~10 % (but not with ~50 %) of TFPI levels displayed elevated lung cytokine and chemokine concentrations 24 hours after infection. None of the groups with low TFPI levels showed an altered procoagulant response in lungs or plasma during pneumonia. These data argue against an important role for endogenous TFPI in the antibacterial, inflammatory and procoagulant response during pneumococcal pneumonia.

  15. Viral and host factors determine innate immune responses in airway epithelial cells from children with wheeze and atopy

    PubMed Central

    Spann, Kirsten M; Baturcam, Engin; Schagen, Johanna; Jones, Carmen; Straub, Claire P; Preston, F Maxine; Chen, Linping; Phipps, Simon; Sly, Peter D; Fantino, Emmanuelle

    2014-01-01

    Background Airway epithelial cells (AEC) from patients with asthma, appear to have an impaired interferon (IFN)-β and -λ response to infection with rhinovirus. Objectives To determine if impaired IFN responses can be identified in young children at risk of developing asthma due to atopy and/or early life wheeze, and if the site of infection or the infecting virus influence the antiviral response. Methods Nasal (N) and tracheal (T) epithelial cells (EC) were collected from children categorised with atopy and/or wheeze based on specific IgE to locally common aeroallergens and a questionnaire concerning respiratory health. Submerged primary cultures were infected with respiratory syncytial virus (RSV) or human metapneumovirus (hMPV), and IFN production, inflammatory cytokine expression and viral replication quantified. Results Nasal epithelial cells (NEC), but not tracheal epithelial cells (TEC), from children with wheeze and/or atopy produced less IFN-β, but not IFN-λ, in response to RSV infection; this was associated with higher viral shedding. However, IFN-regulated factors IRF-7, Mx-1 and CXCL-10, and inflammatory cytokines were not differentially regulated. NECs and TECs from children with wheeze and/or atopy demonstrated no impairment of the IFN response (β or λ) to hMPV infection. Despite this, more hMPV was shed from these cells. Conclusions AECs from children with wheeze and/or atopy do not have an intrinsic defect in the production of IFN-β or -λ, however, this response is influenced by the infecting virus. Higher viral load is associated with atopy and wheeze suggesting an impaired antiviral response to RSV and hMPV that is not influenced by production of IFNs. PMID:24811725

  16. Viral and host factors determine innate immune responses in airway epithelial cells from children with wheeze and atopy.

    PubMed

    Spann, Kirsten M; Baturcam, Engin; Schagen, Johanna; Jones, Carmen; Straub, Claire P; Preston, F Maxine; Chen, Linping; Phipps, Simon; Sly, Peter D; Fantino, Emmanuelle

    2014-10-01

    Airway epithelial cells (AEC) from patients with asthma, appear to have an impaired interferon (IFN)-β and -λ response to infection with rhinovirus. To determine if impaired IFN responses can be identified in young children at risk of developing asthma due to atopy and/or early life wheeze, and if the site of infection or the infecting virus influence the antiviral response. Nasal (N) and tracheal (T) epithelial cells (EC) were collected from children categorised with atopy and/or wheeze based on specific IgE to locally common aeroallergens and a questionnaire concerning respiratory health. Submerged primary cultures were infected with respiratory syncytial virus (RSV) or human metapneumovirus (hMPV), and IFN production, inflammatory cytokine expression and viral replication quantified. Nasal epithelial cells (NEC), but not tracheal epithelial cells (TEC), from children with wheeze and/or atopy produced less IFN-β, but not IFN-λ, in response to RSV infection; this was associated with higher viral shedding. However, IFN-regulated factors IRF-7, Mx-1 and CXCL-10, and inflammatory cytokines were not differentially regulated. NECs and TECs from children with wheeze and/or atopy demonstrated no impairment of the IFN response (β or λ) to hMPV infection. Despite this, more hMPV was shed from these cells. AECs from children with wheeze and/or atopy do not have an intrinsic defect in the production of IFN-β or -λ, however, this response is influenced by the infecting virus. Higher viral load is associated with atopy and wheeze suggesting an impaired antiviral response to RSV and hMPV that is not influenced by production of IFNs. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  17. Nucleotide excision repair is reduced in oral epithelial tissues compared with skin.

    PubMed

    Mitchell, David; Paniker, Lakshmi; Godar, Dianne

    2012-01-01

    Ultraviolet radiation (UVR) exposure to internal tissues for diagnostic, therapeutic and cosmetic procedures has increased dramatically over the past decade. The greatest increase in UVR exposure of internal tissues occurs in the cosmetic industry where it is combined with oxidizing agents for teeth whitening, often in conjunction with indoor tanning. To address potential carcinogenic risks of these procedures, we analyzed the formation and repair of the DNA photoproducts associated with the signature mutations of UVR. Radioimmunoassay was used to quantify the induction and repair of cyclobutane pyrimidine dimers and pyrimidine(6-4)pyrimidone photoproducts in DNA purified from three reconstructed tissues, EpiDerm(TM) , EpiGingival(TM) and EpiOral(TM) . We observed comparable levels of DNA damage in all tissues immediately after UVR exposure. In contrast, repair was significantly reduced in both oral tissues compared with EpiDerm(TM) . Our data suggest that UVR exposure of oral tissues can result in accumulation of DNA damage and increase the risk for carcinoma and melanoma of the mouth. Because NER is a broad-spectrum defense against DNA damage caused by a variety of agents in addition to UVR, our data suggest that the relatively low NER efficiency observed in oral tissues may have wide-ranging consequences in this highly exposed environment.

  18. Comparison of the Effect of Aloe Vera Gel and Nitrofurazone 2% on Epithelialization and Granulation Tissue Formation Regarding Superficial Second-Degree Burns

    PubMed Central

    Irani, Parichehr Sabaghzade; Varaie, Shokoh

    2016-01-01

    Background: Therapeutic effects of various treatment options in burn wound healing have been one of the most controversial issues in wound care. Aloe Vera is an herbal medicine, which has wound healing effects on chronic wound. The present study was carried out to examine and compare the effect of Aloe Vera gel and nitrofurazone 2% on epithelialization and granulation tissue formation with respect to superficial second-degree burns. Methods: This is a randomized clinical trial and the sampling method was used based on pre-defined inclusion criteria. The sample size was 30 patients that were admitted to Kerman burn center, including patients that had superficial burn in the symmetry limb, who were chosen based on depth burn and the qualifications needed for the study. One part of the burned area was dressed using ointment nitrofurazone 2% (according to routine care in the hospital) and the symmetry part was dressed using Aloe Vera gel. The tools for data collection included a demographic questionnaire, tools of bats-joints for checking epithelialization and granulation tissue. The burn wound epithelialization and granulation at the beginning of patient’s admission and the first, second and third weeks after dressing were assessed and recorded. Results: In patients treated with Aloe Vera gel, epithelialization and granulation tissue of burn wounds were remarkably earlier than those patients treated with nitrofurazone 2% (P<0.05). Conclusion: In conclusion, Aloe Vera gel enhanced epithelialization and granulation tissue of burn wounds in superficial second-degree burn patients better than nitrofurazone 2%. The mechanism of the remarkable efficacy of Aloe Vera gel in the epithelialization and granulation tissue of burn injuries may be explained by its hydrocolloid and moisturizing and anti-inflammatory effects. PMID:27516662

  19. Comparison of the Effect of Aloe Vera Gel and Nitrofurazone 2% on Epithelialization and Granulation Tissue Formation Regarding Superficial Second-Degree Burns

    PubMed Central

    Irani, Parichehr Sabaghzade; Varaie, Shokoh

    2016-01-01

    Background: Therapeutic effects of various treatment options in burn wound healing have been one of the most controversial issues in wound care. Aloe Vera is an herbal medicine, which has wound healing effects on chronic wound. The present study was carried out to examine and compare the effect of Aloe Vera gel and nitrofurazone 2% on epithelialization and granulation tissue formation with respect to superficial second-degree burns. Methods: This is a randomized clinical trial and the sampling method was used based on pre-defined inclusion criteria. The sample size was 30 patients that were admitted to Kerman burn center, including patients that had superficial burn in the symmetry limb, who were chosen based on depth burn and the qualifications needed for the study. One part of the burned area was dressed using ointment nitrofurazone 2% (according to routine care in the hospital) and the symmetry part was dressed using Aloe Vera gel. The tools for data collection included a demographic questionnaire, tools of bats-joints for checking epithelialization and granulation tissue. The burn wound epithelialization and granulation at the beginning of patient’s admission and the first, second and third weeks after dressing were assessed and recorded. Results: In patients treated with Aloe Vera gel, epithelialization and granulation tissue of burn wounds were remarkably earlier than those patients treated with nitrofurazone 2% (P<0.05). Conclusion: In conclusion, Aloe Vera gel enhanced epithelialization and granulation tissue of burn wounds in superficial second-degree burn patients better than nitrofurazone 2%. The mechanism of the remarkable efficacy of Aloe Vera gel in the epithelialization and granulation tissue of burn injuries may be explained by its hydrocolloid and moisturizing and anti-inflammatory effects. PMID:27840469

  20. Comparison of the Effect of Aloe Vera Gel and Nitrofurazone 2% on Epithelialization and Granulation Tissue Formation Regarding Superficial Second-Degree Burns.

    PubMed

    Irani, Parichehr Sabaghzade; Varaie, Shokoh

    2016-05-01

    Therapeutic effects of various treatment options in burn wound healing have been one of the most controversial issues in wound care. Aloe Vera is an herbal medicine, which has wound healing effects on chronic wound. The present study was carried out to examine and compare the effect of Aloe Vera gel and nitrofurazone 2% on epithelialization and granulation tissue formation with respect to superficial second-degree burns. This is a randomized clinical trial and the sampling method was used based on pre-defined inclusion criteria. The sample size was 30 patients that were admitted to Kerman burn center, including patients that had superficial burn in the symmetry limb, who were chosen based on depth burn and the qualifications needed for the study. One part of the burned area was dressed using ointment nitrofurazone 2% (according to routine care in the hospital) and the symmetry part was dressed using Aloe Vera gel. The tools for data collection included a demographic questionnaire, tools of bats-joints for checking epithelialization and granulation tissue. The burn wound epithelialization and granulation at the beginning of patient's admission and the first, second and third weeks after dressing were assessed and recorded. In patients treated with Aloe Vera gel, epithelialization and granulation tissue of burn wounds were remarkably earlier than those patients treated with nitrofurazone 2% (P<0.05). In conclusion, Aloe Vera gel enhanced epithelialization and granulation tissue of burn wounds in superficial second-degree burn patients better than nitrofurazone 2%. The mechanism of the remarkable efficacy of Aloe Vera gel in the epithelialization and granulation tissue of burn injuries may be explained by its hydrocolloid and moisturizing and anti-inflammatory effects.

  1. Interplay between the dividing cell and its neighbors regulates adherens junction formation during cytokinesis in epithelial tissue.

    PubMed

    Herszterg, Sophie; Leibfried, Andrea; Bosveld, Floris; Martin, Charlotte; Bellaiche, Yohanns

    2013-02-11

    How adherens junctions (AJs) are formed upon cell division is largely unexplored. Here, we found that AJ formation is coordinated with cytokinesis and relies on an interplay between the dividing cell and its neighbors. During contraction of the cytokinetic ring, the neighboring cells locally accumulate Myosin II and produce the cortical tension necessary to set the initial geometry of the daughter cell interface. However, the neighboring cell membranes impede AJ formation. Upon midbody formation and concomitantly to neighboring cell withdrawal, Arp2/3-dependent actin polymerization oriented by the midbody maintains AJ geometry and regulates AJ final length and the epithelial cell arrangement upon division. We propose that cytokinesis in epithelia is a multicellular process, whereby the cooperative actions of the dividing cell and its neighbors define a two-tiered mechanism that spatially and temporally controls AJ formation while maintaining tissue cohesiveness.

  2. Organotypic three-dimensional culture model of mesenchymal and epithelial cells to examine tissue fusion events.

    EPA Science Inventory

    Tissue fusion during early mammalian development requires coordination of multiple cell types, the extracellular matrix, and complex signaling pathways. Fusion events during processes including heart development, neural tube closure, and palatal fusion are dependent on signaling ...

  3. Organotypic three-dimensional culture model of mesenchymal and epithelial cells to examine tissue fusion events.

    EPA Science Inventory

    Tissue fusion during early mammalian development requires coordination of multiple cell types, the extracellular matrix, and complex signaling pathways. Fusion events during processes including heart development, neural tube closure, and palatal fusion are dependent on signaling ...

  4. Unilateral once daily milking locally induces differential gene expression in both mammary tissue and milk epithelial cells revealing mammary remodeling.

    PubMed

    Boutinaud, Marion; Galio, Laurent; Lollivier, Vanessa; Finot, Laurence; Wiart, Sandra; Esquerré, Diane; Devinoy, Eve

    2013-10-16

    Once daily milking reduces milk yield, but the underlying mechanisms are not yet fully understood. Local regulation due to milk stasis in the tissue may contribute to this effect, but such mechanisms have not yet been fully described. To challenge this hypothesis, one udder half of six Holstein dairy cows was milked once a day (ODM), and the other twice a day (TDM). On the 8th day of unilateral ODM, mammary epithelial cells (MEC) were purified from the milk using immunomagnetic separation. Mammary biopsies were harvested from both udder halves. The differences in transcript profiles between biopsies from ODM and TDM udder halves were analyzed by a 22k bovine oligonucleotide array, revealing 490 transcripts that were differentially expressed. The principal category of upregulated transcripts concerned mechanisms involved in cell proliferation and death. We further confirmed remodeling of the mammary tissue by immunohistochemistry, which showed less cell proliferation and more apoptosis in ODM udder halves. Gene expression analyzed by RT-qPCR in MEC purified from milk and mammary biopsies showed a common downregulation of six transcripts (ABCG2, FABP3, NUCB2, RNASE1 and 5, and SLC34A2) but also some discrepancies. First, none of the upregulated transcripts in biopsies varied in milk-purified MEC. Second, only milk-purified MEC showed significant LALBA downregulation, which suggests therefore that they correspond to a mammary epithelial cell subpopulation. Our results, obtained after unilateral milking, suggest that cell remodeling during ODM is due to a local effect, which may be triggered by milk accumulation.

  5. A tissue-specific role for Nlrp3 in tubular epithelial repair after renal ischemia/reperfusion.

    PubMed

    Bakker, Pieter J; Butter, Loes M; Claessen, Nike; Teske, Gwendoline J D; Sutterwala, Fayyaz S; Florquin, Sandrine; Leemans, Jaklien C

    2014-07-01

    Ischemia/reperfusion injury is a major cause of acute kidney injury. Improving renal repair would represent a therapeutic strategy to prevent renal dysfunction. The innate immune receptor Nlrp3 is involved in tissue injury, inflammation, and fibrosis; however, its role in repair after ischemia/reperfusion is unknown. We address the role of Nlrp3 in the repair phase of renal ischemia/reperfusion and investigate the relative contribution of leukocyte- versus renal-associated Nlrp3 by studying bone marrow chimeric mice. We found that Nlrp3 expression was most profound during the repair phase. Although Nlrp3 expression was primarily expressed by leukocytes, both leukocyte- and renal-associated Nlrp3 was detrimental to renal function after ischemia/reperfusion. The Nlrp3-dependent cytokine IL-1β remained unchanged in kidneys of all mice. Leukocyte-associated Nlrp3 negatively affected tubular apoptosis in mice that lacked Nlrp3 expression on leukocytes, which correlated with reduced macrophage influx. Nlrp3-deficient (Nlrp3KO) mice with wild-type bone marrow showed an improved repair response, as seen by a profound increase in proliferating tubular epithelium, which coincided with increased hepatocyte growth factor expression. In addition, Nlrp3KO tubular epithelial cells had an increased repair response in vitro, as seen by an increased ability of an epithelial monolayer to restore its structural integrity. In conclusion, Nlrp3 shows a tissue-specific role in which leukocyte-associated Nlrp3 is associated with tubular apoptosis, whereas renal-associated Nlrp3 impaired wound healing. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  6. Expression of preoperative KISS1 gene in tumor tissue with epithelial ovarian cancer and its prognostic value.

    PubMed

    Cao, Fang; Chen, Liping; Liu, Manhua; Lin, Weiwei; Ji, Jinlong; You, Jun; Qiao, Fenghai; Liu, Hongbin

    2016-11-01

    Our study aimed to elucidate the role of Kisspeptin (KISS1) in tumor tissues of patients with epithelial ovarian cancer (EOC) and investigate the prognostic value of this biomarker.Forty EOC patients and 20 uterine fibroids female patients with healthy ovaries undergoing cytoreductive surgery between January 2010 and January 2014 in our hospital were enrolled in this study. KISS1 expression in tumor and normal tissues was detected. Correlations between clinic-pathologic variables and KISS1 expression in EOC tissues and the prognostic value of KISS1 for overall survival were evaluated.During the follow-up of 11.2 to 62.1 months, the overall survival rate and mean survival time were 28.9% (11/38) and 38.35 ± 2.84 months. Preoperative KISS1 mRNA was higher in tumor tissue than in normal tissue (P <0.001), and it was associated with histologic grade of tumor, surgical FIGO stage, metastasis, and residual tumor size (all P <0.05). Multivariate survival analysis indicated significant influence of residual tumor size (HR = 2.357, P = 0.039) and preoperative KISS1 mRNA (HR = 0.0001, P <0.001) on mean survival time. Patients with low KISS1 mRNA expression had shorter survival time than those with high expression (P = 0.001).Preoperative KISS1 mRNA was a potential prognostic biomarker for EOC, and high preoperative KISS1 expression indicated a favorable prognosis.

  7. Expression of preoperative KISS1 gene in tumor tissue with epithelial ovarian cancer and its prognostic value

    PubMed Central

    Cao, Fang; Chen, Liping; Liu, Manhua; Lin, Weiwei; Ji, Jinlong; You, Jun; Qiao, Fenghai; Liu, Hongbin

    2016-01-01

    Abstract Our study aimed to elucidate the role of Kisspeptin (KISS1) in tumor tissues of patients with epithelial ovarian cancer (EOC) and investigate the prognostic value of this biomarker. Forty EOC patients and 20 uterine fibroids female patients with healthy ovaries undergoing cytoreductive surgery between January 2010 and January 2014 in our hospital were enrolled in this study. KISS1 expression in tumor and normal tissues was detected. Correlations between clinic-pathologic variables and KISS1 expression in EOC tissues and the prognostic value of KISS1 for overall survival were evaluated. During the follow-up of 11.2 to 62.1 months, the overall survival rate and mean survival time were 28.9% (11/38) and 38.35 ± 2.84 months. Preoperative KISS1 mRNA was higher in tumor tissue than in normal tissue (P <0.001), and it was associated with histologic grade of tumor, surgical FIGO stage, metastasis, and residual tumor size (all P <0.05). Multivariate survival analysis indicated significant influence of residual tumor size (HR = 2.357, P = 0.039) and preoperative KISS1 mRNA (HR = 0.0001, P <0.001) on mean survival time. Patients with low KISS1 mRNA expression had shorter survival time than those with high expression (P = 0.001). Preoperative KISS1 mRNA was a potential prognostic biomarker for EOC, and high preoperative KISS1 expression indicated a favorable prognosis. PMID:27861355

  8. Tissue proteomics of the human mammary gland: towards an abridged definition of the molecular phenotypes underlying epithelial normalcy.

    PubMed

    Moreira, José M A; Cabezón, Teresa; Gromova, Irina; Gromov, Pavel; Timmermans-Wielenga, Vera; Machado, Isidro; Llombart-Bosch, Antonio; Kroman, Niels; Rank, Fritz; Celis, Julio E

    2010-12-01

    Our limited understanding of the biological impact of the whole spectrum of early breast lesions together with a lack of accurate molecular-based risk criteria for the diagnosis and assignment of prognostic significance to biopsy findings presents an important problem in the clinical management of patients harboring precancerous breast lesions. As a result, there is a need to identify biomarkers that can better determine the outcome of early breast lesions by identifying subpopulations of cells in breast premalignant disease that are at high-risk of progression to invasive disease. A first step towards achieving this goal will be to define the molecular phenotypes of the various cell types and precursors - generated by the stem cell hierarchy - that are present in normal and benign conditions of the breast. To date there have been very few systematic proteomic studies aimed at characterizing the phenotypes of the different cell subpopulations present in normal human mammary tissue, partly due to the formidable heterogeneity of mammary tissue, but also due to limitations of the current proteomic technologies. Work in our laboratories has attempted to address in a systematic fashion some of these limitations and here we present our efforts to search for biomarkers using normal fresh tissue from non-neoplastic breast samples. From the data generated by the 2D gel-based proteomic profiling we were able to compile a protein database of normal human breast epithelial tissue that was used to support the biomarker discovery program. We review and present new data on the putative cell-progenitor marker cytokeratin 15 (CK15), and describe a novel marker, dihydropyriminidase-related protein 3 (DRP3) that in combination with CK15 and other well known proteins were used to define molecular phenotypes of normal human breast epithelial cells and their progenitors in resting acini, lactating alveoli, and large collecting ducts of the nipple. Preliminary results are also presented

  9. Community behavior and spatial regulation within a bacterial microcolony in deep tissue sites serves to protect against host attack

    PubMed Central

    Davis, Kimberly M.; Mohammadi, Sina; Isberg, Ralph R.

    2015-01-01

    Summary Bacterial pathogens express virulence-specific transcriptional programs that allow tissue colonization. Although phenotypic variation has been noted in the context of antibiotic exposure, no direct evidence exists for heterogeneity in virulence-specific transcriptional programs within tissues. In a mouse model of Yersinia pseudotuberculosis infection, we show that at least three subpopulations of bacteria develop within a single tissue site in response to distinct host signals. Bacteria growing on the exterior of spleen microcolonies responded to soluble signals and induced the nitric oxide (NO)-detoxifying gene, hmp. Hmp effectively eliminated NO diffusion and protected the interior bacterial population from exposure to NO-derived inducing signals. A third subpopulation, constituting the most peripherally-localized bacteria, directly contacted neutrophils and transcriptionally upregulated a virulence factor. These studies demonstrate that growth within tissues results in transcriptional specialization within a single focus of microbial replication, facilitating directed pathogen counterattack against the host response. PMID:25500192

  10. Quantification of the global and local complexity of the epithelial-connective tissue interface of normal, dysplastic, and neoplastic oral mucosae using digital imaging.

    PubMed

    Abu Eid, Rasha; Landini, Gabriel

    2003-01-01

    This study aimed at quantifying the complexity of the epithelial-connective tissue interface (ECTI) in human normal mucosa, premalignant, and malignant lesions using fractal geometry. Two approaches were used to describe the complexity of 377 oral mucosa ECTI profiles. The box counting method was used to estimate their global fractal dimension, while local fractal dimensions were estimated using the mass radius relation at various local scales. The ECTI complexity significantly increased from normal through premalignant to malignant profiles in both global and local (over 283 microm) scales. Normal mucosa samples from different sites of the oral cavity also had different degrees of global complexity. Fractal geometry is a useful morphological marker of tissue complexity changes taking place during epithelial malignancy and premalignancy, and we propose it as a quantitative marker of epithelial complexity.

  11. The Genes Raw and Ribbon Are Required for Proper Shape of Tubular Epithelial Tissues in Drosophila

    PubMed Central

    Jack, J.; Myette, G.

    1997-01-01

    The products of two genes, raw and ribbon (rib), are required for the proper morphogenesis of a variety of tissues. Malpighian tubules mutant for raw or rib are wider and shorter than normal tubules, which are only two cells in circumference when they are fully formed. The mutations alter the shape of the tubules beginning early in their formation and block cell rearrangement late in development, which normally lengthens and narrows the tubes. Mutations of both genes affect a number of other tissues as well. Both genes are required for dorsal closure and retraction of the CNS during embryonic development. In addition, rib mutations block head involution, and broaden and shorten other tubular epithelia (salivary glands, tracheae, and hindgut) in much same manner as they alter the shape of the Malpighian tubules. In tissues in which the shape of cells can be observed readily, rib mutations alter cell shape, which probably causes the change in shape of the organs that are affected. In double mutants raw enhances the phenotypes of all the tissues that are affected by rib but unaffected by raw alone, indicating that raw is also active in these tissues. PMID:9286684

  12. Microbiota-host interactions in irritable bowel syndrome: epithelial barrier, immune regulation and brain-gut interactions.

    PubMed

    Hyland, Niall P; Quigley, Eamonn M M; Brint, Elizabeth

    2014-07-21

    Irritable bowel syndrome (IBS) is a common, sometimes debilitating, gastrointestinal disorder worldwide. While altered gut motility and sensation, as well as aberrant brain perception of visceral events, are thought to contribute to the genesis of symptoms in IBS, a search for an underlying aetiology has, to date, proven unsuccessful. Recently, attention has been focused on the microbiota as a possible factor in the pathogenesis of IBS. Prompted by a number of clinical observations, such as the recognition of the de novo development of IBS following enteric infections, as well as descriptions of changes in colonic bacterial populations in IBS and supported by clinical responses to interventions, such as antibiotics and probiotics, that modify the microbiota, various approaches have been taken to investigating the microbiota-host response in IBS, as well as in animal models thereof. From such studies a considerable body of evidence has accumulated to indicate the activation or upregulation of both factors involved in bacterial engagement with the host as well host defence mechanisms against bacteria. Alterations in gut barrier function, occurring in response, or in parallel, to changes in the microbiota, have also been widely described and can be seen to play a pivotal role in generating and sustaining host immune responses both within and beyond the gut. In this manner a plausible hypothesis, based on an altered microbiota and/or an aberrant host response, for the pathogenesis, of at least some instances of IBS, can be generated.

  13. Microbiota-host interactions in irritable bowel syndrome: Epithelial barrier, immune regulation and brain-gut interactions

    PubMed Central

    Hyland, Niall P; Quigley, Eamonn MM; Brint, Elizabeth

    2014-01-01

    Irritable bowel syndrome (IBS) is a common, sometimes debilitating, gastrointestinal disorder worldwide. While altered gut motility and sensation, as well as aberrant brain perception of visceral events, are thought to contribute to the genesis of symptoms in IBS, a search for an underlying aetiology has, to date, proven unsuccessful. Recently, attention has been focused on the microbiota as a possible factor in the pathogenesis of IBS. Prompted by a number of clinical observations, such as the recognition of the de novo development of IBS following enteric infections, as well as descriptions of changes in colonic bacterial populations in IBS and supported by clinical responses to interventions, such as antibiotics and probiotics, that modify the microbiota, various approaches have been taken to investigating the microbiota-host response in IBS, as well as in animal models thereof. From such studies a considerable body of evidence has accumulated to indicate the activation or upregulation of both factors involved in bacterial engagement with the host as well host defence mechanisms against bacteria. Alterations in gut barrier function, occurring in response, or in parallel, to changes in the microbiota, have also been widely described and can be seen to play a pivotal role in generating and sustaining host immune responses both within and beyond the gut. In this manner a plausible hypothesis, based on an altered microbiota and/or an aberrant host response, for the pathogenesis, of at least some instances of IBS, can be generated. PMID:25083059

  14. Epithelial and connective tissue healing following electrosurgical incisions in human gingiva.

    PubMed

    Kalkwarf, K L; Krejci, R F; Wentz, F M; Edison, A R

    1983-02-01

    Electrosurgery is used for intraoral incisions by many clinicians. Much controversy surrounds the effect of lateral heat produced during the electrosurgical incision upon the healing of adjacent connective tissue. Ten electrosurgical incisions were made in the gingiva in each of five adult male volunteers. The duration of incision and actual energy production for each incision were calculated. Excisional biopsies of the incisions were obtained at 0-504 hours. At the light microscopic level, epithelium, totally degenerated immediately following the electrosurgery incision, showed extensive activity at 24-48 hours and had covered all wounds by 72 hours. Early hour specimens showed a homogenous connective tissue region, adjacent to the wound site, devoid of cells and fibers. This zone of denatured connective tissue gradually diminished until it was no longer present at 396 hours.

  15. Epithelial-connective tissue interactions induced by thyroid hormone receptor are essential for adult stem cell development in the Xenopus laevis intestine

    PubMed Central

    Hasebe, Takashi; Buchholz, Daniel R.; Shi, Yun-Bo; Ishizuya-Oka, Atsuko

    2012-01-01

    In the amphibian intestine during metamorphosis, stem cells appear and generate the adult absorptive epithelium, analogous to the mammalian one, under the control of thyroid hormone (TH). We have previously shown that the adult stem cells originate from differentiated larval epithelial cells in the Xenopus laevis intestine. To clarify whether TH signaling in the epithelium alone is sufficient for inducing the stem cells, we have now performed tissue recombinant culture experiments, using transgenic X. laevis tadpoles that express a dominant positive TH receptor (dpTR) under a control of heat shock promoter. Wild-type (Wt) or dpTR transgenic (Tg) larval epithelium (Ep) was isolated from the tadpole intestine, recombined with homologous or heterologous non-epithelial tissues (non-Ep), and then cultivated in the absence of TH with daily heat shocks to induce transgenic dpTR expression. Adult epithelial progenitor cells expressing sonic hedgehog became detectable on day 5 in both the recombinant intestine of Tg Ep and Tg non-Ep (Tg/Tg) and that of Tg Ep and Wt non-Ep (Tg/Wt). However, in Tg/Wt intestine, they did not express other stem cell markers such as Musashi-1 and never generated the adult epithelium expressing a marker for absorptive epithelial cells. Our results indicate that, while it is unclear why some larval epithelial cells dedifferentiate into adult progenitor/stem cells, TR-mediated gene expression in the surrounding tissues other than the epithelium is required for them to develop into adult stem cells, suggesting the importance of TH-inducible epithelial-connective tissue interactions in establishment of the stem cell niche in the amphibian intestine. PMID:21280164

  16. Inference of Cell Mechanics in Heterogeneous Epithelial Tissue Based on Multivariate Clone Shape Quantification

    PubMed Central

    Tsuboi, Alice; Umetsu, Daiki; Kuranaga, Erina; Fujimoto, Koichi

    2017-01-01

    Cell populations in multicellular organisms show genetic and non-genetic heterogeneity, even in undifferentiated tissues of multipotent cells during development and tumorigenesis. The heterogeneity causes difference of mechanical properties, such as, cell bond tension or adhesion, at the cell–cell interface, which determine the shape of clonal population boundaries via cell sorting or mixing. The boundary shape could alter the degree of cell–cell contacts and thus influence the physiological consequences of sorting or mixing at the boundary (e.g., tumor suppression or progression), suggesting that the cell mechanics could help clarify the physiology of heterogeneous tissues. While precise inference of mechanical tension loaded at each cell–cell contacts has been extensively developed, there has been little progress on how to distinguish the population-boundary geometry and identify the cause of geometry in heterogeneous tissues. We developed a pipeline by combining multivariate analysis of clone shape with tissue mechanical simulations. We examined clones with four different genotypes within Drosophila wing imaginal discs: wild-type, tartan (trn) overexpression, hibris (hbs) overexpression, and Eph RNAi. Although the clones were previously known to exhibit smoothed or convoluted morphologies, their mechanical properties were unknown. By applying a multivariate analysis to multiple criteria used to quantify the clone shapes based on individual cell shapes, we found the optimal criteria to distinguish not only among the four genotypes, but also non-genetic heterogeneity from genetic one. The efficient segregation of clone shape enabled us to quantitatively compare experimental data with tissue mechanical simulations. As a result, we identified the mechanical basis contributed to clone shape of distinct genotypes. The present pipeline will promote the understanding of the functions of mechanical interactions in heterogeneous tissue in a non-invasive manner. PMID

  17. Peptidoglycan induces loss of a nuclear peptidoglycan recognition protein during host tissue development in a beneficial animal-bacterial symbiosis.

    PubMed

    Troll, Joshua V; Adin, Dawn M; Wier, Andrew M; Paquette, Nicholas; Silverman, Neal; Goldman, William E; Stadermann, Frank J; Stabb, Eric V; McFall-Ngai, Margaret J

    2009-07-01

    Peptidoglycan recognition proteins (PGRPs) are mediators of innate immunity and recently have been implicated in developmental regulation. To explore the interplay between these two roles, we characterized a PGRP in the host squid Euprymna scolopes (EsPGRP1) during colonization by the mutualistic bacterium Vibrio fischeri. Previous research on the squid-vibrio symbiosis had shown that, upon colonization of deep epithelium-lined crypts of the host light organ, symbiont-derived peptidoglycan monomers induce apoptosis-mediated regression of remote epithelial fields involved in the inoculation process. In this study, immunofluorescence microscopy revealed that EsPGRP1 localizes to the nuclei of epithelial cells, and symbiont colonization induces the loss of EsPGRP1 from apoptotic nuclei. The loss of nuclear EsPGRP1 occurred prior to DNA cleavage and breakdown of the nuclear membrane, but followed chromatin condensation, suggesting that it occurs during late-stage apoptosis. Experiments with purified peptidoglycan monomers and with V. fischeri mutants defective in peptidoglycan-monomer release provided evidence that these molecules trigger nuclear loss of EsPGRP1 and apoptosis. The demonstration of a nuclear PGRP is unprecedented, and the dynamics of EsPGRP1 during apoptosis provide a striking example of a connection between microbial recognition and developmental responses in the establishment of symbiosis.

  18. TGF-β1–Containing Exosomes from Injured Epithelial Cells Activate Fibroblasts to Initiate Tissue Regenerative Responses and Fibrosis

    PubMed Central

    Borges, Fernanda T.; Melo, Sonia A.; Özdemir, Berna C.; Kato, Noritoshi; Revuelta, Ignacio; Miller, Caroline A.; Gattone, Vincent H.; LeBleu, Valerie S.

    2013-01-01

    Hypoxia is associated with tissue injury and fibrosis but its functional role in fibroblast activation and tissue repair/regeneration is unknown. Using kidney injury as a model system, we demonstrate that injured epithelial cells produce an increased number of exosomes with defined genetic information to activate fibroblasts. Exosomes released by injured epithelial cells promote proliferation, α-smooth muscle actin expression, F-actin expression, and type I collagen production in fibroblasts. Fibroblast activation is dependent on exosomes delivering TGF-β1 mRNA among other yet to be identified moieties. This study suggests that TGF-β1 mRNA transported by exosomes constitutes a rapid response to initiate tissue repair/regenerative responses and activation of fibroblasts when resident parenchyma is injured. The results also inform potential utility of exosome-targeted therapies to control tissue fibrosis. PMID:23274427

  19. Palifermin for the protection and regeneration of epithelial tissues following injury: new findings in basic research and pre-clinical models

    PubMed Central

    Finch, Paul W; Mark Cross, Lawrence J; McAuley, Daniel F; Farrell, Catherine L

    2013-01-01

    Keratinocyte growth factor (KGF) is a paracrine-acting epithelial mitogen produced by cells of mesenchymal origin, that plays an important role in protecting and repairing epithelial tissues. Pre-clinical data initially demonstrated that a recombinant truncated KGF (palifermin) could reduce gastrointestinal injury and mortality resulting from a variety of toxic exposures. Furthermore, the use of palifermin in patients with hematological malignancies reduced the incidence and duration of severe oral mucositis experienced after intensive chemoradiotherapy. Based upon these findings, as well as the observation that KGF receptors are expressed in many, if not all, epithelial tissues, pre-clinical studies have been conducted to determine the efficacy of palifermin in protecting different epithelial tissues from toxic injury in an attempt to model various clinical situations in which it might prove to be of benefit in limiting tissue damage. In this article, we review these studies to provide the pre-clinical background for clinical trials that are described in the accompanying article and the rationale for additional clinical applications of palifermin. PMID:24151975

  20. Palifermin for the protection and regeneration of epithelial tissues following injury: new findings in basic research and pre-clinical models.

    PubMed

    Finch, Paul W; Mark Cross, Lawrence J; McAuley, Daniel F; Farrell, Catherine L

    2013-09-01

    Keratinocyte growth factor (KGF) is a paracrine-acting epithelial mitogen produced by cells of mesenchymal origin, that plays an important role in protecting and repairing epithelial tissues. Pre-clinical data initially demonstrated that a recombinant truncated KGF (palifermin) could reduce gastrointestinal injury and mortality resulting from a variety of toxic exposures. Furthermore, the use of palifermin in patients with hematological malignancies reduced the incidence and duration of severe oral mucositis experienced after intensive chemoradiotherapy. Based upon these findings, as well as the observation that KGF receptors are expressed in many, if not all, epithelial tissues, pre-clinical studies have been conducted to determine the efficacy of palifermin in protecting different epithelial tissues from toxic injury in an attempt to model various clinical situations in which it might prove to be of benefit in limiting tissue damage. In this article, we review these studies to provide the pre-clinical background for clinical trials that are described in the accompanying article and the rationale for additional clinical applications of palifermin.

  1. The proliferative activity of mammary epithelial cells in normal tissue predicts breast cancer risk in premenopausal women

    PubMed Central

    Huh, Sung Jin; Oh, Hannah; Peterson, Michael A.; Almendro, Vanessa; Hu, Rong; Bowden, Michaela; Lis, Rosina L.; Cotter, Maura B.; Loda, Massimo; Barry, William T.; Polyak, Kornelia; Tamimi, Rulla M.

    2016-01-01

    The frequency and proliferative activity of tissue-specific stem and progenitor cells are suggested to correlate with cancer risk. In this study, we investigated the association between breast cancer risk and the frequency of mammary epithelial cells expressing p27, estrogen receptor (ER), and Ki67 in normal breast tissue. We performed a nested case-control study of 302 women (69 breast cancer cases, 233 controls) who had been initially diagnosed with benign breast disease according to the Nurses’ Health Studies. Immunofluorescence for p27, ER, and Ki67 was performed on tissue microarrays constructed from benign biopsies containing normal mammary epithelium and scored by computational image analysis. We found that the frequency of Ki67+ cells was positively associated with breast cancer risk among premenopausal women (odds ratio [OR]=10.1, 95% confidence interval [CI]=2.12–48.0). Conversely, the frequency of ER+ or p27+ cells was inversely, but not significantly, associated with subsequent breast cancer risk (ER+: OR=0.70, 95% CI=0.33–1.50; p27+: OR=0.89, 95% CI=0.45–1.75). Notably, high Ki67+/low p27+ and high Ki67+/low ER+ cell frequencies were significantly associated with a 5-fold higher risk of breast cancer compared to low Ki67+/low p27+ and low Ki67+/low ER+ cell frequencies, respectively, among premenopausal women (Ki67hi/p27lo: OR=5.08, 95% CI=1.43–18.1; Ki67hi/ERlo: OR=4.68, 95% CI=1.63–13.5). Taken together, our data suggest that the fraction of actively cycling cells in normal breast tissue may represent a marker for breast cancer risk assessment, which may therefore impact the frequency of screening procedures in at-risk women. PMID:26941287

  2. Flavan-3-ols and proanthocyanidins from Limonium brasiliense inhibit the adhesion of Porphyromonas gingivalis to epithelial host cells by interaction with gingipains.

    PubMed

    de Oliveira Caleare, Angelo; Hensel, Andreas; Mello, João Carlos Palazzo; Pinha, Andressa Blainski; Panizzon, Gean Pier; Lechtenberg, Matthias; Petereit, Frank; Nakamura, Celso Vataru

    2017-04-01

    Porphyromonas gingivalis is a pathogen strongly involved in chronic and aggressive forms of periodontitis. Natural products, mainly polyphenols, have been described for advanced treatment of periodontitis by inhibition of the bacterial adhesion of P. gingivalis to the epithelial host cells. An acetone:water extract (LBE) from the rhizomes of Limonium brasiliense (Boiss.) Kuntze was tested under in vitro conditions for potential antiadhesive effects against P. gingivalis to human KB cells and for inhibition of the proteolytic activity of gingipains, the main virulence factor of P. gingivalis. LBE≤100μg/mL had no cytotoxicity against the bacteria and did not influence the cell physiology of human epithelial KB cells. At 100μg/mL LBE reduced the adhesion of P. gingivalis to KB cells significantly by about 80%. LBE at 20μg/mL reduced the proteolytic activity of the arginin-specific Rgp gingipain by about 75%. Chemical profiling of LBE indicated the presence of gallic acid, epigallocatechin-3-O-gallate and samarangenins A and B as lead compounds. UHPLC by using MS and UV detection displays a suitable method for quality control of the extract for identification and quantification of the lead compounds.

  3. The contribution of tumor and host tissue factor expression to oncogene-driven gliomagenesis.

    PubMed

    Magnus, Nathalie; Meehan, Brian; Garnier, Delphine; Hashemi, Maryam; Montermini, Laura; Lee, Tae Hoon; Milsom, Chloe; Pawlinski, Rafal; Ohlfest, John; Anderson, Mark; Mackman, Nigel; Rak, Janusz

    2014-11-14

    Glioblastoma multiforme (GBM) is an aggressive form of glial brain tumors, associated with angiogenesis, thrombosis, and upregulation of tissue factor (TF), the key cellular trigger of coagulation and signaling. Since TF is upregulated by oncogenic mutations occurring in different subsets of human brain tumors we investigated whether TF contributes to tumourigenesis driven by oncogenic activation of EGFR (EGFRvIII) and RAS pathways in the brain. Here we show that TF expression correlates with poor prognosis in glioma, but not in GBM. In situ, the TF protein expression is heterogeneously expressed in adult and pediatric gliomas. GBM cells harboring EGFRvIII (U373vIII) grow aggressively as xenografts in SCID mice and their progression is delayed by administration of monoclonal antibodies blocking coagulant (CNTO 859) and signaling (10H10) effects of TF in vivo. Mice in which TF gene is disrupted in the neuroectodermal lineage exhibit delayed progression of spontaneous brain tumors driven by oncogenic N-ras and SV40 large T antigen (SV40LT) expressed under the control of sleeping beauty transposase. Reduced host TF levels in low-TF/SCID hypomorphic mice mitigated growth of glioma subcutaneously but not in the brain. Thus, we suggest that tumor-associated TF may serve as therapeutic target in the context of oncogene-driven disease progression in a subset of glioma.

  4. Ecosystem engineering and manipulation of host plant tissues by the insect borer Oncideres albomarginata chamela.

    PubMed

    Calderón-Cortés, Nancy; Uribe-Mú, Claudia A; Martínez-Méndez, A Karen; Escalera-Vázquez, Luis H; Cristobal-Pérez, E Jacob; García-Oliva, Felipe; Quesada, Mauricio

    2016-01-01

    Ecosystem engineering by insect herbivores occurs as the result of structural modification of plants manipulated by insects. However, only few studies have evaluated the effect of these modifications on the plant responses induced by stem-borers that act as ecosystem engineers. In this study, we evaluated the responses induced by the herbivory of the twig-girdler beetle Oncideres albomarginata chamela (Cerambycidae: Lamiinae) on its host plant Spondias purpurea (Anacardiaceae), and its relationship with the ecosystem engineering process carried out by this stem-borer. Our results demonstrated that O. albomarginata chamela branch removal induced the development of lateral branches increasing the resources needed for the development of future insect generations, of its own offspring and of many other insect species. Detached branches represent habitats with high content of nitrogen and phosphorous, which eventually can be incorporated into the ecosystem, increasing nutrient cycling efficiency. Consequently, branch removal and the subsequent plant tissue regeneration induced by O. albomarginata chamela represent key mechanisms underlying the ecosystem engineering process carried out by this stem-borer, which enhances arthropod diversity in the ecosystem. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. The coxsackie- and adenovirus receptor (CAR) is an in vivo marker for epithelial tight junctions, with a potential role in regulating permeability and tissue homeostasis.

    PubMed

    Raschperger, Elisabeth; Thyberg, Johan; Pettersson, Sven; Philipson, Lennart; Fuxe, Jonas; Pettersson, Ralf F

    2006-05-15

    The coxsackie- and adenovirus receptor (CAR) is a transmembrane protein belonging to the immunoglobulin superfamily. The function of CAR as a virus receptor has been extensively analyzed, while its physiological role and expression pattern in adult tissues have remained less clear. CAR associates with epithelial tight junctions in vitro and mediates cell-cell adhesion. Using a set of affinity-purified antibodies, we show that CAR is predominantly expressed in epithelial cells lining the body cavities in adult mice, where it specifically co-localizes with the tight junction components ZO-1 and occludin. Notably, CAR could not be detected in endothelial cells of the vasculature, including brain capillaries. CAR expression correlated positively with the maturity of tight junctions and inversely with permeability. With a few exceptions, the two known CAR isoforms were co-expressed in most epithelial cells analyzed. A CAR mutant lacking the intracellular tail over-expressed in transgenic mice was diffusely localized over the plasma membrane, showing the importance of this domain for correct subcellular localization in vivo. We conclude that CAR is localized to epithelial tight junctions in vivo where it may play a role in the regulation of epithelial permeability and tissue homeostasis.

  6. Epithelial sodium channel (ENaC) family: Phylogeny, structure-function, tissue distribution, and associated inherited diseases.

    PubMed

    Hanukoglu, Israel; Hanukoglu, Aaron

    2016-04-01

    The epithelial sodium channel (ENaC) is composed of three homologous subunits and allows the flow of Na(+) ions across high resistance epithelia, maintaining body salt and water homeostasis. ENaC dependent reabsorption of Na(+) in the kidney tubules regulates extracellular fluid (ECF) volume and blood pressure by modulating osmolarity. In multi-ciliated cells, ENaC is located in cilia and plays an essential role in the regulation of epithelial surface liquid volume necessary for cilial transport of mucus and gametes in the respiratory and reproductive tracts respectively. The subunits that form ENaC (named as alpha, beta, gamma and delta, encoded by genes SCNN1A, SCNN1B, SCNN1G, and SCNN1D) are members of the ENaC/Degenerin superfamily. The earliest appearance of ENaC orthologs is in the genomes of the most ancient vertebrate taxon, Cyclostomata (jawless vertebrates) including lampreys, followed by earliest representatives of Gnathostomata (jawed vertebrates) including cartilaginous sharks. Among Euteleostomi (bony vertebrates), Actinopterygii (ray finned-fishes) branch has lost ENaC genes. Yet, most animals in the Sarcopterygii (lobe-finned fish) branch including Tetrapoda, amphibians and amniotes (lizards, crocodiles, birds, and mammals), have four ENaC paralogs. We compared the sequences of ENaC orthologs from 20 species and established criteria for the identification of ENaC orthologs and paralogs, and their distinction from other members of the ENaC/Degenerin superfamily, especially ASIC family. Differences between ENaCs and ASICs are summarized in view of their physiological functions and tissue distributions. Structural motifs that are conserved throughout vertebrate ENaCs are highlighted. We also present a comparative overview of the genotype-phenotype relationships in inherited diseases associated with ENaC mutations, including multisystem pseudohypoaldosteronism (PHA1B), Liddle syndrome, cystic fibrosis-like disease and essential hypertension. Copyright

  7. Epithelial sodium channel (ENaC) family: Phylogeny, structure-function, tissue distribution, and associated inherited diseases

    PubMed Central

    Hanukoglu, Israel; Hanukoglu, Aaron

    2016-01-01

    The epithelial sodium channel (ENaC) is composed of three homologous subunits and allows the flow of Na+ ions across high resistance epithelia, maintaining body salt and water homeostasis. ENaC dependent reabsorption of Na+ in the kidney tubules regulates extracellular fluid (ECF) volume and blood pressure by modulating osmolarity. In multi-ciliated cells, ENaC is located in cilia and plays an essential role in the regulation of epithelial surface liquid volume necessary for cilial transport of mucus and gametes in the respiratory and reproductive tracts respectively. The subunits that form ENaC (named as alpha, beta, gamma and delta, encoded by genes SCNN1A, SCNN1B, SCNN1G, and SCNN1D) are members of the ENaC/Degenerin superfamily. The earliest appearance of ENaC orthologs is in the genomes of the most ancient vertebrate taxon, Cyclostomata (jawless vertebrates) including lampreys, followed by earliest representatives of Gnathostomata (jawed vertebrates) including cartilaginous sharks. Among Euteleostomi (bony vertebrates), Actinopterygii (ray finned-fishes) branch has lost ENaC genes. Yet, most animals in the Sarcopterygii (lobe-finned fish) branch including Tetrapoda, amphibians and amniotes (lizards, crocodiles, birds, and mammals), have four ENaC paralogs. We compared the sequences of ENaC orthologs from 20 species and established criteria for the identification of ENaC orthologs and paralogs, and their distinction from other members of the ENaC/Degenerin superfamily, especially ASIC family. Differences between ENaCs and ASICs are summarized in view of their physiological functions and tissue distributions. Structural motifs that are conserved throughout vertebrate ENaCs are highlighted. We also present a comparative overview of the genotype-phenotype relationships in inherited diseases associated with ENaC mutations, including multisystem pseudohypoaldosteronism (PHA1B), Liddle syndrome, cystic fibrosis-like disease and essential hypertension. PMID:26772908

  8. Genomic Modifiers of Natural Killer Cells, Immune Responsiveness and Lymphoid Tissue Remodeling Together Increase Host Resistance to Viral Infection

    PubMed Central

    Lee, Heather; Prince, Jessica; Stadnisky, Michael D.; Anderson, Monique; Nash, William; Rival, Claudia; Wei, Hairong; Gamache, Awndre; Farber, Charles R.; Tung, Kenneth; Brown, Michael G.

    2016-01-01

    The MHC class I Dk molecule supplies vital host resistance during murine cytomegalovirus (MCMV) infection. Natural killer (NK) cells expressing the Ly49G2 inhibitory receptor, which specifically binds Dk, are required to control viral spread. The extent of Dk-dependent host resistance, however, differs significantly amongst related strains of mice, C57L and MA/My. As a result, we predicted that relatively small-effect modifier genetic loci might together shape immune cell features, NK cell reactivity, and the host immune response to MCMV. A robust Dk-dependent genetic effect, however, has so far hindered attempts to identify additional host resistance factors. Thus, we applied genomic mapping strategies and multicolor flow cytometric analysis of immune cells in naive and virus-infected hosts to identify genetic modifiers of the host immune response to MCMV. We discovered and validated many quantitative trait loci (QTL); these were mapped to at least 19 positions on 16 chromosomes. Intriguingly, one newly discovered non-MHC locus (Cmv5) controlled splenic NK cell accrual, secondary lymphoid organ structure, and lymphoid follicle development during MCMV infection. We infer that Cmv5 aids host resistance to MCMV infection by expanding NK cells needed to preserve and protect essential tissue structural elements, to enhance lymphoid remodeling and to increase viral clearance in spleen. PMID:26845690

  9. MicroRNA-203 inhibits the progression of esophageal squamous cell carcinoma with restored epithelial tissue architecture in vivo.

    PubMed

    Okumura, Tomoyuki; Shimada, Yutaka; Moriyama, Makoto; Takei, Yoshinori; Omura, Tetsuya; Sekine, Shinichi; Nagata, Takuya; Shimizu, Kazuharu; Tsukada, Kazuhiro

    2014-06-01

    MicroRNA (miR)-203 has been shown to induce squamous differentiation of epidermal stem cells through the suppression of p63. The aim of this study was to assess the tumor suppressor effect of miR-203 in esophageal squamous cell carcinoma (ESCC) with focus on the regulation of the cell fate decisions and organization of tumor tissue architecture in vivo. Our investigation establishing stable clones from ESCC cell lines with induced miR-203 expression resulted in significant growth inhibition in a mouse xenograft model. Small foci were observed in xenograft tumors with stratified squamous differentiation in conjunction with restored baso-apical polarity. The expression of the basement membrane protein laminine was localized at the center of the foci and the basal cell marker p75NTR was expressed in the innermost layer. The expression of ki67 and p63 was co-localized at the center layers, while involucrin was expressed in the outer layers. Flow cytometry revealed that the p75NTR-positive cells expressing p63 and Bmi1 were well maintained, while the expression of p63 was suppressed in the p75NTR-negative cells. Our cDNA microarray analysis demonstrated the upregulation of genes involved in regulating tissue architecture, such as BMP-4 and ZO-1 in the mir-203 transfectant. Investigation using surgically removed ESCC specimens revealed that the expression of miR-203 significantly correlated with a favorable prognosis. These results demonstrated that miR-203 regulated both basal and supra-basal cell components to induce differentiation with restored epithelial tissue architecture, leading to significant tumor growth inhibition in vivo. Those results suggest the use of miR-203 as a novel therapeutic and diagnostic target in patients with ESCC.

  10. The development of a simplified epithelial tissue phantom for the evaluation of an autofluorescence mitigation algorithm

    NASA Astrophysics Data System (ADS)

    Hou, Vivian W.; Yang, Chenying; Nelson, Leonard Y.; Seibel, Eric J.

    2014-03-01

    Previously we developed an ultrathin, flexible, multimodal scanning fiber endoscope (SFE) for concurrent white light and fluorescence imaging. Autofluorescence (AF) arising from endogenous fluorophores (primarily collagen in the esophagus) act as major confounders in fluorescence-aided detection. To address the issue of AF, a real-time mitigation algorithm was developed and has been show to successfully remove AF during SFE imaging. To test our algorithm, we previously developed flexible, color-matched, synthetic phantoms featuring a homogenous distribution of collagen. In order to more rigorously test the AF mitigation algorithm, a phantom that better mimicked the in-vivo distribution of collagen in tissue was developed.

  11. Identification of host transcriptional networks showing concentration-dependent regulation by HPV16 E6 and E7 proteins in basal cervical squamous epithelial cells

    PubMed Central

    Smith, Stephen P.; Scarpini, Cinzia G.; Groves, Ian J.; Odle, Richard I.; Coleman, Nicholas

    2016-01-01

    Development of cervical squamous cell carcinoma requires increased expression of the major high-risk human-papillomavirus (HPV) oncogenes E6 and E7 in basal cervical epithelial cells. We used a systems biology approach to identify host transcriptional networks in such cells and study the concentration-dependent changes produced by HPV16-E6 and -E7 oncoproteins. We investigated sample sets derived from the W12 model of cervical neoplastic progression, for which high quality phenotype/genotype data were available. We defined a gene co-expression matrix containing a small number of highly-connected hub nodes that controlled large numbers of downstream genes (regulons), indicating the scale-free nature of host gene co-expression in W12. We identified a small number of ‘master regulators’ for which downstream effector genes were significantly associated with protein levels of HPV16 E6 (n = 7) or HPV16 E7 (n = 5). We validated our data by depleting E6/E7 in relevant cells and by functional analysis of selected genes in vitro. We conclude that the network of transcriptional interactions in HPV16-infected basal-type cervical epithelium is regulated in a concentration-dependent manner by E6/E7, via a limited number of central master-regulators. These effects are likely to be significant in cervical carcinogenesis, where there is competitive selection of cells with elevated expression of virus oncoproteins. PMID:27457222

  12. Identification of host transcriptional networks showing concentration-dependent regulation by HPV16 E6 and E7 proteins in basal cervical squamous epithelial cells.

    PubMed

    Smith, Stephen P; Scarpini, Cinzia G; Groves, Ian J; Odle, Richard I; Coleman, Nicholas

    2016-07-26

    Development of cervical squamous cell carcinoma requires increased expression of the major high-risk human-papillomavirus (HPV) oncogenes E6 and E7 in basal cervical epithelial cells. We used a systems biology approach to identify host transcriptional networks in such cells and study the concentration-dependent changes produced by HPV16-E6 and -E7 oncoproteins. We investigated sample sets derived from the W12 model of cervical neoplastic progression, for which high quality phenotype/genotype data were available. We defined a gene co-expression matrix containing a small number of highly-connected hub nodes that controlled large numbers of downstream genes (regulons), indicating the scale-free nature of host gene co-expression in W12. We identified a small number of 'master regulators' for which downstream effector genes were significantly associated with protein levels of HPV16 E6 (n = 7) or HPV16 E7 (n = 5). We validated our data by depleting E6/E7 in relevant cells and by functional analysis of selected genes in vitro. We conclude that the network of transcriptional interactions in HPV16-infected basal-type cervical epithelium is regulated in a concentration-dependent manner by E6/E7, via a limited number of central master-regulators. These effects are likely to be significant in cervical carcinogenesis, where there is competitive selection of cells with elevated expression of virus oncoproteins.

  13. Inhibitory Activity of YKL-40 in Mammary Epithelial Cell Differentiation and Polarization Induced by Lactogenic Hormones: A Role in Mammary Tissue Involution

    PubMed Central

    Scully, Steve; Yan, Wei; Bentley, Brooke; Cao, Qing Jackie; Shao, Rong

    2011-01-01

    We previously reported that a secreted glycoprotein YKL-40 acts as an angiogenic factor to promote breast cancer angiogenesis. However, its functional role in normal mammary gland development is poorly understood. Here we investigated its biophysiological activity in mammary epithelial development and mammary tissue morphogenesis. YKL-40 was expressed exclusively by ductal epithelial cells of parous and non-parous mammary tissue, but was dramatically up-regulated at the beginning of involution. To mimic ductal development and explore activity of elevated YKL-40 during mammary tissue regression in vivo, we grew a mammary epithelial cell line 76N MECs in a 3-D Matrigel system in the presence of lactogenic hormones including prolactin, hydrocortisone, and insulin. Treatment of 76N MECs with recombinant YKL-40 significantly inhibited acinar formation, luminal polarization, and secretion. YKL-40 also suppressed expression of E-cadherin but increased MMP-9 and cell motility, the crucial mechanisms that mediate mammary tissue remodeling during involution. In addition, engineering of 76N MECs with YKL-40 gene to express ectopic YKL-40 recapitulated the same activities as recombinant YKL-40 in the inhibition of cell differentiation. These results suggest that YKL-40-mediated inhibition of cell differentiation and polarization in the presence of lactogenic hormones may represent its important function during mammary tissue involution. Identification of this biophysiological property will enhance our understanding of its pathologic role in the later stage of breast cancer that is developed from poorly differentiated and highly invasive cells. PMID:21991364

  14. Ocular surface reconstruction with a tissue-engineered nasal mucosal epithelial cell sheet for the treatment of severe ocular surface diseases.

    PubMed

    Kobayashi, Masakazu; Nakamura, Takahiro; Yasuda, Makoto; Hata, Yuiko; Okura, Shoki; Iwamoto, Miyu; Nagata, Maho; Fullwood, Nigel J; Koizumi, Noriko; Hisa, Yasuo; Kinoshita, Shigeru

    2015-01-01

    Severe ocular surface diseases (OSDs) with severe dry eye can be devastating and are currently some of the most challenging eye disorders to treat. To investigate the feasibility of using an autologous tissue-engineered cultivated nasal mucosal epithelial cell sheet (CNMES) for ocular surface reconstruction, we developed a novel technique for the culture of nasal mucosal epithelial cells expanded ex vivo from biopsy-derived human nasal mucosal tissues. After the protocol, the CNMESs had 4-5 layers of stratified, well-differentiated cells, and we successfully generated cultured epithelial sheets, including numerous goblet cells. Immunohistochemistry confirmed the presence of keratins 3, 4, and 13; mucins 1, 16, and 5AC; cell junction and basement membrane assembly proteins; and stem/progenitor cell marker p75 in the CNMESs. We then transplanted the CNMESs onto the ocular surfaces of rabbits and confirmed the survival of this tissue, including the goblet cells, up to 2 weeks. The present report describes an attempt to overcome the problems of treating severe OSDs with the most severe dry eye by treating them using tissue-engineered CNMESs to supply functional goblet cells and to stabilize and reconstruct the ocular surface. The present study is a first step toward assessing the use of tissue-engineered goblet-cell transplantation of nonocular surface origin for ocular surface reconstruction.

  15. The micronutrient zinc inhibits EAEC strain 042 adherence, biofilm formation, virulence gene expression, and epithelial cytokine responses benefiting the infected host

    PubMed Central

    Medeiros, Pedro; Bolick, David T; Roche, James K; Noronha, Francisco; Pinheiro, Caio; Kolling, Glynis L; Lima, Aldo; Guerrant, Richard L

    2013-01-01

    Enteroaggregative Escherichia coli (EAEC) is a major pathogen worldwide, associated with diarrheal disease in both children and adults, suggesting the need for new preventive and therapeutic treatments. We investigated the role of the micronutrient zinc in the pathogenesis of an E. coli strain associated with human disease. A variety of bacterial characteristics—growth in vitro, biofilm formation, adherence to IEC-6 epithelial cells, gene expression of putative EAEC virulence factors as well as EAEC-induced cytokine expression by HCT-8 cells—were quantified. At concentrations (≤ 0.05 mM) that did not alter EAEC growth (strain 042) but that are physiologic in serum, zinc markedly decreased the organism’s ability to form biofilm (P < 0.001), adhere to IEC-6 epithelial cells (P < 0.01), and express putative EAEC virulence factors (aggR, aap, aatA, virK) (P < 0.03). After exposure of the organism to zinc, the effect on virulence factor generation was prolonged (>3 h). Further, EAEC-induced IL-8 mRNA and protein secretion by HCT-8 epithelial cells were significantly reduced by 0.05 mM zinc (P < 0.03). Using an in vivo murine model of diet-induced zinc-deficiency, oral zinc supplementation (0.4 µg/mouse daily) administered after EAEC challenge (1010 CFU/mouse) significantly abrogated growth shortfalls (by >90%; P < 0.01); furthermore, stool shedding was reduced (days 9–11) but tissue burden of organisms in the intestine was unchanged. These findings suggest several potential mechanisms whereby physiological levels of zinc alter pathogenetic events in the bacterium (reducing biofilm formation, adherence to epithelium, virulence factor expression) as well as the bacterium’s effect on the epithelium (cytokine response to exposure to EAEC) to alter EAEC pathogenesis in vitro and in vivo. These effects may help explain and extend the benefits of zinc in childhood diarrhea and malnutrition. PMID:23958904

  16. Meningococcal interactions with the host.

    PubMed

    Carbonnelle, Etienne; Hill, Darryl J; Morand, Philippe; Griffiths, Natalie J; Bourdoulous, Sandrine; Murillo, Isabel; Nassif, Xavier; Virji, Mumtaz

    2009-06-24

    Neisseria meningitidis interacts with host tissues through hierarchical, concerted and co-ordinated actions of a number of adhesins; many of which undergo antigenic and phase variation, a strategy that helps immune evasion. Three major structures, pili, Opa and Opc predominantly influence bacterial adhesion to host cells. Pili and Opa proteins also determine host and tissue specificity while Opa and Opc facilitate efficient cellular invasion. Recent studies have also implied a role of certain adhesin-receptor pairs in determining increased host susceptibility to infection. This chapter examines our current knowledge of meningococcal adhesion and invasion mechanisms particularly related to human epithelial and endothelial cells which are of primary importance in the disease process.

  17. Ecotoxicoparasitology: Understanding mercury concentrations in gut contents, intestinal helminths and host tissues of Alaskan gray wolves (Canis lupus)

    USGS Publications Warehouse

    McGrew, Ashley K.; O'Hara, Todd M.; Stricker, Craig A.; Castellini, Margaret; Beckmen, Kimberlee B.; Salman, Mo D.; Ballweber, Lora R.

    2015-01-01

    Some gastrointestinal helminths acquire nutrients from the lumen contents in which they live; thus, they may be exposed to non-essential elements, such as mercury (Hg), during feeding. The objectives of this study were: 1) determine the total mercury concentrations ([THg]) in Gray wolves (Canis lupus) and their parasites, and 2) use stable isotopes to evaluate the trophic relationships within the host. [THg] and stable isotopes (C and N) were determined for helminths, host tissues, and lumen contents from 88 wolves. Sixty-three wolves contained grossly visible helminths (71.5%). The prevalence of taeniids and ascarids was 63.6% (56/88) and 20.5% (18/88), respectively. Nine of these 63 wolves contained both taeniids and ascarids (14.3%). All ascarids were determined to beToxascaris leonina. Taenia species present included T. krabbei and T. hydatigena. Within the GI tract, [THg] in the lumen contents of the proximal small intestine were significantly lower than in the distal small intestine. There was a significant positive association between hepatic and taeniid [THg]. Bioaccumulation factors (BAF) ranged from < 1 to 22.9 in taeniids, and 1.1 to 12.3 in T. leonina. Taeniid and ascarid BAF were significantly higher than 1, suggesting that both groups are capable of THg accumulation in their wolf host. δ13C in taeniids was significantly lower than in host liver and skeletal muscle. [THg] in helminths and host tissues, in conjunction with stable isotope (C and N) values, provides insight into food-web dynamics of the host GI tract, and aids in elucidating ecotoxicoparasitologic relationships. Variation of [THg] throughout the GI tract, and between parasitic groups, underscores the need to further evaluate the effect(s) of feeding niche, and the nutritional needs of parasites, as they relate to toxicant exposure and distribution within the host.

  18. Ecotoxicoparasitology: Understanding mercury concentrations in gut contents, intestinal helminths and host tissues of Alaskan gray wolves (Canis lupus)

    PubMed Central

    McGrew, Ashley K.; O'Hara, Todd M.; Stricker, Craig A.; Castellini, J. Margaret; Beckmen, Kimberlee B.; Salman, Mo D.; Ballweber, Lora R.

    2015-01-01

    Some gastrointestinal helminths acquire nutrients from the lumen contents in which they live; thus, they may be exposed to non-essential elements, such as mercury (Hg), during feeding. The objectives of this study were: 1) determine the total mercury concentrations ([THg]) in Gray wolves (Canis lupus) and their parasites, and 2) use stable isotopes to evaluate the trophic relationships within the host. [THg] and stable isotopes (C and N) were determined for helminths, host tissues, and lumen contents from 88 wolves. Sixty-three wolves contained grossly visible helminths (71.5%). The prevalence of taeniids and ascarids was 63.6% (56/88) and 20.5% (18/88), respectively. Nine of these 63 wolves contained both taeniids and ascarids (14.3%). All ascarids were determined to be Toxascaris leonina. Taenia species present included T. krabbei and T. hydatigena. Within the GI tract, [THg] in the lumen contents of the proximal small intestine were significantly lower than in the distal small intestine. There was a significant positive association between hepatic and taeniid [THg]. Bioaccumulation factors (BAF) ranged from <1 to 22.9 in taeniids, and 1.1 to 12.3 in Toxascaris leonina. Taeniid and ascarid BAF were significantly higher than 1, suggesting that both groups are capable of THg accumulation in their wolf host. δ13C in taeniids was significantly lower than in host liver and skeletal muscle. [THg] in helminths and host tissues, in conjunction with stable isotope (C and N) values, provides insight into food-web dynamics of the host GI tract, and aids in elucidating ecotoxicoparasitologic relationships. Variation of [THg] throughout the GI tract, and between parasitic groups, underscores the need to further evaluate the effect(s) of feeding niche, and the nutritional needs of parasites, as they relate to toxicant exposure and distribution within the host. PMID:26283618

  19. Ecotoxicoparasitology: Understanding mercury concentrations in gut contents, intestinal helminths and host tissues of Alaskan gray wolves (Canis lupus).

    PubMed

    McGrew, Ashley K; O'Hara, Todd M; Stricker, Craig A; Castellini, J Margaret; Beckmen, Kimberlee B; Salman, Mo D; Ballweber, Lora R

    2015-12-01

    Some gastrointestinal helminths acquire nutrients from the lumen contents in which they live; thus, they may be exposed to non-essential elements, such as mercury (Hg), during feeding. The objectives of this study were: 1) determine the total mercury concentrations ([THg]) in Gray wolves (Canis lupus) and their parasites, and 2) use stable isotopes to evaluate the trophic relationships within the host. [THg] and stable isotopes (C and N) were determined for helminths, host tissues, and lumen contents from 88 wolves. Sixty-three wolves contained grossly visible helminths (71.5%). The prevalence of taeniids and ascarids was 63.6% (56/88) and 20.5% (18/88), respectively. Nine of these 63 wolves contained both taeniids and ascarids (14.3%). All ascarids were determined to be Toxascaris leonina. Taenia species present included T. krabbei and T. hydatigena. Within the GI tract, [THg] in the lumen contents of the proximal small intestine were significantly lower than in the distal small intestine. There was a significant positive association between hepatic and taeniid [THg]. Bioaccumulation factors (BAF) ranged from <1 to 22.9 in taeniids, and 1.1 to 12.3 in T. leonina. Taeniid and ascarid BAF were significantly higher than 1, suggesting that both groups are capable of THg accumulation in their wolf host. δ13C in taeniids was significantly lower than in host liver and skeletal muscle. [THg] in helminths and host tissues, in conjunction with stable isotope (C and N) values, provides insight into food-web dynamics of the host GI tract, and aids in elucidating ecotoxicoparasitologic relationships. Variation of [THg] throughout the GI tract, and between parasitic groups, underscores the need to further evaluate the effect(s) of feeding niche, and the nutritional needs of parasites, as they relate to toxicant exposure and distribution within the host.

  20. Host-Integration of a Tissue-Engineered Airway Patch: Two-Year Follow-Up in a Single Patient

    PubMed Central

    Dally, Iris; Friedel, Godehard; Walles, Heike; Walles, Thorsten

    2015-01-01

    Different bioengineering techniques have been applied repeatedly for the reconstruction of extensive airway defects in the last few years. While short-term surgical success is evident, there is a lack of long-term results in patients. Here, we report the case of a young male who received a 5×2 cm bioartificial airway patch for tracheoesophageal reconstruction focusing on clinical defect healing and histomorphological tissue reorganization 2.5 years after surgery. We generated bioartificial airway tissue using a cell-free biological vascularized scaffold that was re-endothelialized and reseeded with the recipient's autologous primary cells and we implanted it into the recipient's left main bronchus. To investigate host-integration 2.5 years after the implantation, we obtained biopsies of the implant and adjacent tracheal tissue and processed these for histological and immunohistochemical analyses. The early postoperative course was uneventful and the transplanted airway tissue was integrated into the host. 2.5 years after transplantation, a bronchoscopy confirmed the scar-free reconstruction of the former airway defect. Histological work-up documented respiratory airway mucosa lining the bronchial reconstruction, making it indistinguishable from native airway mucosa. After transplantation, our bioartificial airway tissue provided perfect airway healing, with no histological evidence of tissue dedifferentiation. PMID:25316325

  1. TGF-β signal rewiring sustains epithelial-mesenchymal transition of circulating tumor cells in prostate cancer xenograft hosts

    PubMed Central

    Huang, Guangcun; Osmulski, Pawel A.; Bouamar, Hakim; Mahalingam, Devalingam; Lin, Chun-Lin; Liss, Michael A.; Kumar, Addanki Pratap; Chen, Chun-Liang; Thompson, Ian M.; Sun, Lu-Zhe; Gaczynska, Maria E.; Huang, Tim H.-M.

    2016-01-01

    Activation of TGF-β signaling is known to promote epithelial-mesenchymal transition (EMT) for the development of metastatic castration-resistant prostate cancer (mCRPC). To determine whether targeting TGF-β signaling alone is sufficient to mitigate mCRPC, we used the CRISPR/Cas9 genome-editing approach to generate a dominant-negative mutation of the cognate receptor TGFBRII that attenuated TGF-β signaling in mCRPC cells. As a result, the delicate balance of oncogenic homeostasis is perturbed, profoundly uncoupling proliferative and metastatic potential of TGFBRII-edited tumor xenografts. This signaling disturbance triggered feedback rewiring by enhancing ERK signaling known to promote EMT-driven metastasis. Circulating tumor cells displaying upregulated EMT genes had elevated biophysical deformity and an increase in interactions with chaperone macrophages for facilitating metastatic extravasation. Treatment with an ERK inhibitor resulted in decreased aggressive features of CRPC cells in vitro. Therefore, combined targeting of TGF-β and its backup partner ERK represents an attractive strategy for treating mCRPC patients. PMID:27780930

  2. Tissue dual RNA-seq allows fast discovery of infection-specific functions and riboregulators shaping host-pathogen transcriptomes.

    PubMed

    Nuss, Aaron M; Beckstette, Michael; Pimenova, Maria; Schmühl, Carina; Opitz, Wiebke; Pisano, Fabio; Heroven, Ann Kathrin; Dersch, Petra

    2017-01-31

    Pathogenic bacteria need to rapidly adjust their virulence and fitness program to prevent eradication by the host. So far, underlying adaptation processes that drive pathogenesis have mostly been studied in vitro, neglecting the true complexity of host-induced stimuli acting on the invading pathogen. In this study, we developed an unbiased experimental approach that allows simultaneous monitoring of genome-wide infection-linked transcriptional alterations of the host and colonizing extracellular pathogens. Using this tool for Yersinia pseudotuberculosis-infected lymphatic tissues, we revealed numerous alterations of host transcripts associated with inflammatory and acute-phase responses, coagulative activities, and transition metal ion sequestration, highlighting that the immune response is dominated by infiltrating neutrophils and elicits a mixed TH17/TH1 response. In consequence, the pathogen's response is mainly directed to prevent phagocytic attacks. Yersinia up-regulates the gene and expression dose of the antiphagocytic type III secretion system (T3SS) and induces functions counteracting neutrophil-induced ion deprivation, radical stress, and nutritional restraints. Several conserved bacterial riboregulators were identified that impacted this response. The strongest influence on virulence was found for the loss of the carbon storage regulator (Csr) system, which is shown to be essential for the up-regulation of the T3SS on host cell contact. In summary, our established approach provides a powerful tool for the discovery of infection-specific stimuli, induced host and pathogen responses, and underlying regulatory processes.

  3. Response to rhinovirus infection by human airway epithelial cells and peripheral blood mononuclear cells in an in vitro two-chamber tissue culture system.

    PubMed

    Rajan, Devi; Gaston, Kelsey A; McCracken, Courtney E; Erdman, Dean D; Anderson, Larry J

    2013-01-01

    Human rhinovirus (HRV) infections are associated with the common cold, occasionally with more serious lower respiratory tract illnesses, and frequently with asthma exacerbations. The clinical features of HRV infection and its association with asthma exacerbation suggest that some HRV disease results from virus-induced host immune responses to infection. To study the HRV-infection-induced host responses and the contribution of these responses to disease, we have developed an in vitro model of HRV infection of human airway epithelial cells (Calu-3 cells) and subsequent exposure of human peripheral blood mononuclear cells (PBMCs) to these infected cells in a two-chamber trans-well tissue culture system. Using this model, we studied HRV 14 (species B) and HRV 16 (species A) induced cytokine and chemokine responses with PBMCs from four healthy adults. Infection of Calu-3 cells with either virus induced HRV-associated increases in FGF-Basic, IL-15, IL-6, IL-28A, ENA-78 and IP-10. The addition of PBMCs to HRV 14-infected cells gave significant increases in MIP-1β, IL-28A, MCP-2, and IFN-α as compared with mock-infected cells. Interestingly, ENA-78 levels were reduced in HRV 14 infected cells that were exposed to PBMCs. Addition of PBMCs to HRV 16-infected cells did not induce MIP-1β, IL-28A and IFN-α efficiently nor did it decrease ENA-78 levels. Our results demonstrate a clear difference between HRV 14 and HRV 16 and the source of PBMCs, in up or down regulation of several cytokines including those that are linked to airway inflammation. Such differences might be one of the reasons for variation in disease associated with different HRV species including variation in their link to asthma exacerbations as suggested by other studies. Further study of immune responses associated with different HRVs and PBMCs from different patient groups, and the mechanisms leading to these differences, should help characterize pathogenesis of HRV disease and generate novel approaches to

  4. Epithelial, metabolic and innate immunity transcriptomic signatures differentiating the rumen from other sheep and mammalian gastrointestinal tract tissues

    PubMed Central

    Xiang, Ruidong; Oddy, Victor Hutton; Archibald, Alan L.; Vercoe, Phillip E.

    2016-01-01

    Background. Ruminants are successful herbivorous mammals, in part due to their specialized forestomachs, the rumen complex, which facilitates the conversion of feed to soluble nutrients by micro-organisms. Is the rumen complex a modified stomach expressing new epithelial (cornification) and metabolic programs, or a specialised stratified epithelium that has acquired new metabolic activities, potentially similar to those of the colon? How has the presence of the rumen affected other sections of the gastrointestinal tract (GIT) of ruminants compared to non-ruminants? Methods. Transcriptome data from 11 tissues covering the sheep GIT, two stratified epithelial and two control tissues, was analysed using principal components to cluster tissues based on gene expression profile similarity. Expression profiles of genes along the sheep GIT were used to generate a network to identify genes enriched for expression in different compartments of the GIT. The data from sheep was compared to similar data sets from two non-ruminants, pigs (closely related) and humans (more distantly related). Results. The rumen transcriptome clustered with the skin and tonsil, but not the GIT transcriptomes, driven by genes from the epidermal differentiation complex, and genes encoding stratified epithelium keratins and innate immunity proteins. By analysing all of the gene expression profiles across tissues together 16 major clusters were identified. The strongest of these, and consistent with the high turnover rate of the GIT, showed a marked enrichment of cell cycle process genes (P = 1.4 E−46), across the whole GIT, relative to liver and muscle, with highest expression in the caecum followed by colon and rumen. The expression patterns of several membrane transporters (chloride, zinc, nucleosides, amino acids, fatty acids, cholesterol and bile acids) along the GIT was very similar in sheep, pig and humans. In contrast, short chain fatty acid uptake and metabolism appeared to be different

  5. Tissue Harvesting Site and Culture Medium Affect Attachment, Growth, and Phenotype of Ex Vivo Expanded Oral Mucosal Epithelial Cells.

    PubMed

    Islam, Rakibul; Eidet, Jon Roger; Badian, Reza A; Lippestad, Marit; Messelt, Edward; Griffith, May; Dartt, Darlene A; Utheim, Tor Paaske

    2017-04-06

    Transplantation of cultured oral mucosal epithelial cells (OMECs) is a promising treatment strategy for limbal stem cell deficiency. In order to improve the culture method, we investigated the effects of four culture media and tissue harvesting sites on explant attachment, growth, and phenotype of OMECs cultured from Sprague-Dawley rats. Neither choice of media or harvesting site impacted the ability of the explants to attach to the culture well. Dulbecco's modified Eagle's medium/Ham's F12 (DMEM) and Roswell Park Memorial Institute 1640 medium (RPMI) supported the largest cellular outgrowth. Fold outgrowth was superior from LL explants compared to explants from the buccal mucosa (BM), HP, and transition zone of the lower lip (TZ) after six-day culture. Putative stem cell markers were detected in cultures grown in DMEM and RPMI. In DMEM, cells from TZ showed higher colony-forming efficiency than LL, BM, and HP. In contrast to RPMI, DMEM both expressed the putative stem cell marker Bmi-1 and yielded cell colonies. Our data suggest that OMECs from LL and TZ cultured in DMEM give rise to undifferentiated cells with high growth capacity, and hence are the most promising for treatment of limbal stem cell deficiency.

  6. Lipoprotein Lipase, Tissue Expression and Effects on Genes Related to Fatty Acid Synthesis in Goat Mammary Epithelial Cells

    PubMed Central

    Zhao, Wang-Sheng; Hu, Shi-Liang; Yu, Kang; Wang, Hui; Wang, Wei; Loor, Juan; Luo, Jun

    2014-01-01

    Lipoprotein lipase (LPL) serves as a central factor in hydrolysis of triacylglycerol and uptake of free fatty acids from the plasma. However, there are limited data concerning the action of LPL on the regulation of milk fat synthesis in goat mammary gland. In this investigation, we describe the cloning and sequencing of the LPL gene from Xinong Saanen dairy goat mammary gland, along with a study of its phylogenetic relationships. Sequence analysis showed that goat LPL shares similarities with other species including sheep, bovine, human and mouse. LPL mRNA expression in various tissues determined by RT-qPCR revealed the highest expression in white adipose tissue, with lower expression in heart, lung, spleen, rumen, small intestine, mammary gland, and kidney. Expression was almost undetectable in liver and muscle. The expression profiles of LPL gene in mammary gland at early, peak, mid, late lactation, and the dry period were also measured. Compared with the dry period, LPL mRNA expression was markedly greater at early lactation. However, compared with early lactation, the expression was lower at peak lactation and mid lactation. Despite those differences, LPL mRNA expression was still greater at peak, mid, and late lactation compared with the dry period. Using goat mammary epithelial cells (GMEC), the in vitro knockdown of LPL via shRNA or with Orlistat resulted in a similar degree of down-regulation of LPL (respectively). Furthermore, knockdown of LPL was associated with reduced mRNA expression of SREBF1, FASN, LIPE and PPARG but greater expression of FFAR3. There was no effect on ACACA expression. Orlistat decreased expression of LIPE, FASN, ACACA, and PPARG, and increased FFAR3 and SREBF1 expression. The pattern of LPL expression was similar to the changes in milk fat percentage in lactating goats. Taken together, results suggest that LPL may play a crucial role in fatty acid synthesis. PMID:25501331

  7. Sub-epithelial connective tissue graft for root coverage in nonsmokers and smokers: A pilot comparative clinical study

    PubMed Central

    Dwarakanath, Chini Doraswamy; Divya, Bheemavarapu; Sruthima, Gottumukkala Naga Venkata Satya; Penmetsa, Gautami Subadra

    2016-01-01

    Background: Gingival recession is a common condition and is more prevalent in smokers. It is widely believed that root coverage procedures in smokers result in less desirable outcome compared to nonsmokers', and there are few controlled studies in literature to support this finding. Therefore, the purpose of this study was to evaluate and compare the outcome of root coverage with sub-epithelial connective tissue graft (SCTG) in nonsmokers and smokers. Materials and Methods: A sample of twenty subjects, 10 nonsmokers and 10 smokers were selected each with at least 1 Miller's Class I or II recession on a single rooted tooth. Clinical measurements of probing depth, clinical attachment level (CAL), gingival recession total surface area (GRTSA), depth of recession (RD), width of recession (RW), and width of keratinized tissue were determined at baseline, 3, and 6 months after surgery. Results: The treatment of gingival recession with SCTG and coronally advanced flap showed a decrease in the GRTSA, RD, RW, and an increase in CAL and width of keratinized gingiva in both the groups. However, the intergroup comparison of the clinical parameters showed no statistical significance. About 6 out of 10 nonsmokers (60%) and 3 smokers (30%) showed complete root coverage. The mean percentage of root coverage of 71.2% in nonsmokers and 38% in smokers was observed. Conclusion: The results of the present study suggest that smoking may negatively influence gingival recession reduction and CAL gain. In addition, smokers may exhibit fewer chances of complete root coverage. Overall, nonsmokers showed better improvements in all the parameters compared to smokers at the end of 6 months.

  8. Epithelial control of gut-associated lymphoid tissue formation through p38α-dependent restraint of NF-κB signaling

    PubMed Central

    Caballero-Franco, Celia; Guma, Monica; Choo, Min-Kyung; Sano, Yasuyo; Enzler, Thomas; Karin, Michael; Mizoguchi, Atsushi; Park, Jin Mo

    2015-01-01

    The protein kinase p38α mediates cellular responses to environmental and endogenous cues that direct tissue homeostasis and immune responses. Studies of mice lacking p38α in several different cell types have demonstrated that p38α signaling is essential to maintaining the proliferation-differentiation balance in developing and steady-state tissues. The mechanisms underlying these roles involve cell-autonomous control of signaling and gene expression by p38α. Here we show that p38α regulates gut-associated lymphoid tissue (GALT) formation in a non-cell-autonomous manner. From an investigation of mice with intestinal epithelial cell-specific deletion of the p38α gene, we find that p38α serves to limit NF-κB signaling and thereby attenuate GALT-promoting chemokine expression in the intestinal epithelium. Loss of this regulation results in GALT hyperplasia and, in some animals, mucosa-associated B cell lymphoma. These anomalies occur independently of luminal microbial stimuli and are likely driven by direct epithelial-lymphoid interactions. Our study illustrates a novel p38α-dependent mechanism preventing excessive generation of epithelial-derived signals that drive lymphoid tissue overgrowth and malignancy. PMID:26792803

  9. Sub-Periosteal Dissection with Denture-Guided Epithelial Regeneration: A Novel Method for Peri-Implant Soft Tissue Management in Reconstructed Mandibles.

    PubMed

    Kumar, Vinay V; Jacob, P C; Kuriakose, Moni A

    2016-12-01

    In patients with reconstructed mandibles using free fibula flaps, management of soft tissues around implants supporting dental rehabilitation, is often a clinical problem. The aim of this paper is to describe a new technique, namely "Sub-periosteal dissection and denture-guided epithelial regeneration (SD-DGER)", as a method of peri-implant soft tissue management in these patients. The technique consists of performing a subperiosteal dissection with creation of buccal and lingual flaps. These flaps form the buccal and lingual vestibule. Implants are placed and an interim denture is immediately loaded onto the implants to guide the regenerated epithelium. A keratinized mucosal layer is formed on the bare fibula bone in six months time. This technique was successful in producing fixed keratinized epithelial tissue around implants in patients with mandibles reconstructed using the free fibula flap in patients who did not undergo radiotherapy. The sub-periosteal dissection with denture guided epithelial regeneration is a predictable form of peri-implant soft tissue management in selected patients with reconstructed jaws.

  10. Epithelial Control of Gut-Associated Lymphoid Tissue Formation through p38α-Dependent Restraint of NF-κB Signaling.

    PubMed

    Caballero-Franco, Celia; Guma, Monica; Choo, Min-Kyung; Sano, Yasuyo; Enzler, Thomas; Karin, Michael; Mizoguchi, Atsushi; Park, Jin Mo

    2016-03-01

    The protein kinase p38α mediates cellular responses to environmental and endogenous cues that direct tissue homeostasis and immune responses. Studies of mice lacking p38α in several different cell types have demonstrated that p38α signaling is essential to maintaining the proliferation-differentiation balance in developing and steady-state tissues. The mechanisms underlying these roles involve cell-autonomous control of signaling and gene expression by p38α. In this study, we show that p38α regulates gut-associated lymphoid tissue (GALT) formation in a noncell-autonomous manner. From an investigation of mice with intestinal epithelial cell-specific deletion of the p38α gene, we find that p38α serves to limit NF-κB signaling and thereby attenuate GALT-promoting chemokine expression in the intestinal epithelium. Loss of this regulation results in GALT hyperplasia and, in some animals, mucosa-associated B cell lymphoma. These anomalies occur independently of luminal microbial stimuli and are most likely driven by direct epithelial-lymphoid interactions. Our study illustrates a novel p38α-dependent mechanism preventing excessive generation of epithelial-derived signals that drive lymphoid tissue overgrowth and malignancy.

  11. In vitro systems toxicology approach to investigate the effects of repeated cigarette smoke exposure on human buccal and gingival organotypic epithelial tissue cultures

    PubMed Central

    Schlage, Walter K.; Kostadinova, Radina; Xiang, Yang; Sewer, Alain; Majeed, Shoaib; Kuehn, Diana; Frentzel, Stefan; Talikka, Marja; Geertz, Marcel; Mathis, Carole; Ivanov, Nikolai; Hoeng, Julia; Peitsch, Manuel C.

    2014-01-01

    Smoking has been associated with diseases of the lung, pulmonary airways and oral cavity. Cytologic, genomic and transcriptomic changes in oral mucosa correlate with oral pre-neoplasia, cancer and inflammation (e.g. periodontitis). Alteration of smoking-related gene expression changes in oral epithelial cells is similar to that in bronchial and nasal epithelial cells. Using a systems toxicology approach, we have previously assessed the impact of cigarette smoke (CS) seen as perturbations of biological processes in human nasal and bronchial organotypic epithelial culture models. Here, we report our further assessment using in vitro human oral organotypic epithelium models. We exposed the buccal and gingival organotypic epithelial tissue cultures to CS at the air–liquid interface. CS exposure was associated with increased secretion of inflammatory mediators, induction of cytochrome P450s activity and overall weak toxicity in both tissues. Using microarray technology, gene-set analysis and a novel computational modeling approach leveraging causal biological network models, we identified CS impact on xenobiotic metabolism-related pathways accompanied by a more subtle alteration in inflammatory processes. Gene-set analysis further indicated that the CS-induced pathways in the in vitro buccal tissue models resembled those in the in vivo buccal biopsies of smokers from a published dataset. These findings support the translatability of systems responses from in vitro to in vivo and demonstrate the applicability of oral organotypical tissue models for an impact assessment of CS on various tissues exposed during smoking, as well as for impact assessment of reduced-risk products. PMID:25046638

  12. In vitro systems toxicology approach to investigate the effects of repeated cigarette smoke exposure on human buccal and gingival organotypic epithelial tissue cultures.

    PubMed

    Schlage, Walter K; Iskandar, Anita R; Kostadinova, Radina; Xiang, Yang; Sewer, Alain; Majeed, Shoaib; Kuehn, Diana; Frentzel, Stefan; Talikka, Marja; Geertz, Marcel; Mathis, Carole; Ivanov, Nikolai; Hoeng, Julia; Peitsch, Manuel C

    2014-10-01

    Smoking has been associated with diseases of the lung, pulmonary airways and oral cavity. Cytologic, genomic and transcriptomic changes in oral mucosa correlate with oral pre-neoplasia, cancer and inflammation (e.g. periodontitis). Alteration of smoking-related gene expression changes in oral epithelial cells is similar to that in bronchial and nasal epithelial cells. Using a systems toxicology approach, we have previously assessed the impact of cigarette smoke (CS) seen as perturbations of biological processes in human nasal and bronchial organotypic epithelial culture models. Here, we report our further assessment using in vitro human oral organotypic epithelium models. We exposed the buccal and gingival organotypic epithelial tissue cultures to CS at the air-liquid interface. CS exposure was associated with increased secretion of inflammatory mediators, induction of cytochrome P450s activity and overall weak toxicity in both tissues. Using microarray technology, gene-set analysis and a novel computational modeling approach leveraging causal biological network models, we identified CS impact on xenobiotic metabolism-related pathways accompanied by a more subtle alteration in inflammatory processes. Gene-set analysis further indicated that the CS-induced pathways in the in vitro buccal tissue models resembled those in the in vivo buccal biopsies of smokers from a published dataset. These findings support the translatability of systems responses from in vitro to in vivo and demonstrate the applicability of oral organotypical tissue models for an impact assessment of CS on various tissues exposed during smoking, as well as for impact assessment of reduced-risk products.

  13. Innate mechanisms for Bifidobacterium lactis to activate transient pro-inflammatory host responses in intestinal epithelial cells after the colonization of germ-free rats

    PubMed Central

    Ruiz, Pedro A; Hoffmann, Micha; Szcesny, Silke; Blaut, Michael; Haller, Dirk

    2005-01-01

    Bifidobacteria comprise a dominant microbial population group in the human intestinal tract with purported beneficial health effects on the host. In this study, we characterized the molecular mechanisms for the initial interaction of probiotic Bifidobacterium lactis strain BB12 with native and intestinal epithelial cell (IEC) lines. We showed that B. lactis-monoassociated Fisher F344 rats transiently induce phosphorylation/activation of the NF-κB transcriptionally active subunit RelA and the mitogen-activated protein kinase (MAPK) p38 in native IEC at day 5 after initial bacterial colonization. In addition, Interleukin 6 (IL-6) gene expression was significantly increased at day 5, demonstrating the physiological relevance of transient transcription factor activation in IEC. In contrast, Bacteroides vulgatus-monoassociated Fisher rats revealed RelA but not p38 MAPK phosphorylation and failed to trigger significant IL-6 gene expression in native IEC. Moreover, we demonstrated that B. lactis triggers NF-κB RelA and p38 MAPK phosphorylation in IEC lines. Adenoviral delivery of mutant IKK-β (Ad5dnIKKβ) and inhibition of the p38 MAPK pathway through the pharmacological inhibitor SB203580 significantly blocked B. lactis-induced IL-6 gene expression in IEC, suggesting that B. lactis triggers NF-κB and MAPK signaling to induce gene expression in the intestinal epithelium. Regarding the mechanisms of bacteria epithelial cell cross-talk, B. lactis-induced IL-6 gene expression was completely inhibited in TLR2 deficient mouse embryogenic fibroblasts (MEF TLR2−/−) as well as TLR2ΔTIR transfected Mode-K cells. In conclusion, we demonstrated that probiotic bacteria transiently trigger innate signal transduction and pro-inflammatory gene expression in the intestinal epithelium at early stages of bacterial colonization. PMID:16011513

  14. The role of polysaccharide intercellular adhesin (PIA) in Staphylococcus epidermidis adhesion to host tissues and subsequent antibiotic tolerance.

    PubMed

    Costa, A R; Henriques, M; Oliveira, R; Azeredo, J

    2009-06-01

    The aim of this study was to determine the role of polysaccharide intercellular adhesin (PIA) in Staphylococcus epidermidis adhesion to host tissues and subsequent antibiotic tolerance. The adherence of S. epidermidis 1457 and the mutant defective in PIA production (1457-M10) to urinary epithelium and endothelium was estimated by colony counting. Minimum bactericidal concentration and mean reduction of cellular activity (XTT) following antibiotic exposure was determined for planktonic and adhered bacteria. S. epidermidis 1457 adhered to a greater extent to both cells than the mutant strain. The adhered strains had a significantly higher antimicrobial tolerance than their planktonic counterparts. The mutant strain was, in general, the most susceptible to the antibiotics assayed. In conclusion, PIA may influence S. epidermidis adherence to host tissues and their antimicrobial susceptibility. Initial adhesion may be the main step for the acquisition of resistance in S. epidermidis.

  15. A STUDY OF THE SPECIFIC LOCATION OF LEPTOSPIRES WITH RESPECT TO VARIOUS TISSUE CELLS OF INFECTED ANIMAL HOSTS.

    DTIC Science & Technology

    The objectives of the research were as follows: (1) To determine the specific location of leptospires with respect to various tissue cells of the...infected animal host. (2) To study histologic variations at the cellular level as a result of leptospiral activity. (3) To determine final...disposition and significance of morphologically intact leptospires within vesicular structures of hepatic and renal cells and (4) To compare the 3341 and MLS

  16. How important is tumour shape? Quantification of the epithelial-connective tissue interface in oral lesions using local connected fractal dimension analysis.

    PubMed

    Landini, G; Rippin, J W

    1996-06-01

    Quantification of the local complexity of the epithelial-connective tissue interface (ECTI) in normal mucosa, epithelial dysplasia, and squamous cell carcinoma of the floor of the mouth was investigated by estimating the local connected fractal dimension in tissue profiles from histological sections. The use of certain parameters of the distribution of the local connected fractal dimensions of the ECTI classifies the cases belonging to these three histopathological diagnoses with 85 per cent accuracy by means of linear discriminant analysis. The values of the local fractal dimension were also used to produce colour-coded dimensional images of the ECTI, to highlight locations with higher irregularity that may correlate with locally invasive 'higher-risk' areas.

  17. Developing a quantitative in vivo tissue reconstitution assay to assess the relative potency of candidate populations of mouse oesophageal epithelial cells.

    PubMed

    Croagh, Daniel; Redvers, Rick; Phillips, Wayne A; Kaur, Pritinder

    2012-01-01

    Proliferation in mouse oesophageal epithelial cells is confined to the basal layer of the epithelium. Within this population, it is possible to discriminate different sub-populations using a combination of cell kinetic studies and functional assays. In particular, it is possible to distinguish basal epithelial cells, which are post-mitotic and destined to leave the basal layer and differentiate compared with those cells that remain in the cycling pool. Within the cycling basal population, there appears to be a hierarchy with respect to the rate of cell turnover which may reflect a hierarchy of "stemness", although it has not been possible to demonstrate functional differences between these populations using current in vivo tissue reconstitution assays. The aim of this chapter is to describe the development of a quantitative in vivo tissue reconstitution assay to assess the potency of candidate stem cell populations within the mouse oesophageal epithelium.

  18. Abnormal Localization and Tumor Suppressor Function of Epithelial Tissue-Specific Transcription Factor ESE3 in Esophageal Squamous Cell Carcinoma.

    PubMed

    Wang, Li; Xing, Jie; Cheng, Rui; Shao, Ying; Li, Peng; Zhu, Shengtao; Zhang, Shutian

    2015-01-01

    Esophageal cancer is one of the most common malignant cancers worldwide. The molecular mechanism of esophageal squamous cell carcinoma (ESCC) is still poorly understood. ESE3 is a member of the Ets transcription family, which is only expressed in epithelial tissues and acts as a tumor suppressor gene in prostate cancer. Our study aim was to confirm whether ESE3 is involved in the carcinogenesis of ESCC. Immunohistochemical analysis revealed that ESE3 was mainly located in cell nuclei of normal tissues and the cytoplasm in ESCC tissues. Immunofluorescence and western blot analyses of the normal esophageal cell line HEEpiC and ESCC cell lines EC9706 TE-1, KYSE150, and KYSE410 confirmed these results. pEGFP-ESE3 and pcDNA3.1-V5/HisA-ESE3 plasmids were constructed for overexpression of ESE3 in EC9706 and KYSE150 cells. The stably transfected cells showed restoration of the nuclear localization of ESE3. EC9706 cells with re-localization of ESE3 to the nucleus showed inhibition of proliferation, colony formation, migration, and invasion. To explore the possible mechanism of the differences in localization of ESE3 in normal esophageal cells and ESCC cells, ESCC cell lines were treated with the nuclear export inhibitor leptomycin B, transcription inhibitor actinomycin D, PKC inhibitor sphinganine, P38 MAPK inhibitor SB202190, and CK II inhibitor TBCA. These reagents were chosen according to the well-known mechanisms of protein translocation. However, the localization of ESE3 was unchanged after these treatments. The sequence of ESE3 cDNA in ESCC cells was identical to the standard sequence of ESE3 in the NCBI Genebank database, indicating that there was no mutation in the coding region of ESE3 in ESCC. Taken together, our study suggests that ESE3 plays an important role in the carcinogenesis of ESCC through changes in subcellular localization and may act as a tumor suppressor gene in ESCC, although the mechanisms require further study.

  19. Expression of the carbohydrate tumour marker SLeX, SLeA (CA19-9), LeY and Thomsen-Friedenreich (TF) antigen on normal squamous epithelial tissue of the penis and vagina.

    PubMed

    Wiest, Irmi; Schulze, Sandra; Kuhn, Christina; Seliger, Christian; Hausmann, Roland; Betz, Peter; Mayr, Doris; Friese, Klaus; Jeschke, Udo

    2007-01-01

    Sialyl Lewis x (SLeX), sialyl Lewis a (SLeA), Lewis Y (LeY) and the Thomsen-Friedenreich (TF) antigen are carbohydrate motifs that mediate the adhesion between tumour cells and the endothelium. These antigens are usually not expressed in non-malignant tissue. Overexpression of SLeX and SLeA is combined with poor prognosis and malignant relapse. In this study, we analysed the combined expression of SLeX, SLeA, LeY and TF in normal squamous epithelium tissue of the penis shaft, glans and foreskin and in addition of the vagina and vulva. Paraffin-embedded slides of vaginal tissue (8), vulva tissue (8) and penis shaft (8) and glans tissue (8) were fixed and incubated with monoclonal antibodies against SLeX (IgM), SLeA (IgM), LeY (IgM) and TF (IgM). Staining reaction was performed with ABC reagent. The intensity of immunohistochemical reaction on images of the slides was analyzed using a semiquantitative score. Strong focal expression of both sialyl Lewis antigens was found in the uretra of the penis shaft and on epithelial tissue of the glans, and permanent moderate expression of SLeX and SLeA in squamous epithelial tissue of the vagina. Moderate expression of TF was observed in male squamous epithelial tissues of the glans and foreskin and faint expression of TF was found in vulval epithelial tissue. Faint expression of Le Y was observed in female vulval epithelial tissue. Expression of SLeX, SLeA, LeY and especially of the TF antigen in normal non malignant epithelial tissue is surprising and can be explained by the function of this tissue in human reproduction. In addition, moderate TF expression seems to be restricted to epithelial tissue of the penis glans and foreskin.

  20. Detection of epithelial cell transfer in spinal areas by light microscopy and determining any tissue coring via cell culture during combined spinal-epidural interventions.

    PubMed

    Tunali, Yusuf; Kaya, Guner; Tunali, Gulden; Solakoglu, Seyhun; Yenice, Sedef; Bahar, Mois

    2006-01-01

    Epithelial tissue coring by spinal needles during subarachnoid injections may cause intraspinal epidermal tumors. Previous studies have investigated tissue transfer with different needle types during subarachnoid or epidural injection. This study deals with the transfer of epithelial tissue during combined spinal-epidural (CSE) anesthesia. We studied 68 American Society of Anesthesiologists I to III adult patients. CSE anesthesia was induced under aseptic conditions at the L2-3 or L3-4 interspace with patients in the lateral decubitus position. Cerebral spinal fluid, spinal needle stylet, fluid used to flush the interior of the spinal needle, fluid used to wash the exterior of the spinal needle, fluid used to flush the interior of the epidural needle, and fluid used to wash the exterior tip of the epidural needle were examined under light microscopy (n = 30 patients) or incubated in a cell-culture medium (n = 38 patients). Samples were incubated in cell-culture medium alone (n = 13) or in a cell-culture medium for 3 weeks and then in a medium with epidermal growth factor (n = 25). As a positive control, skin tissue samples were taken by punch biopsy from 10 randomly chosen patients who underwent CSE interventions. These samples were incubated in an enriched medium serum. Light microscopy revealed that there was cell transfer in all phases in various rates: samples 1, 2, 3, 4, 5, and 6 contained epithelial cells and debris in ratios of 6.9%, 20.7%, 6.9%, 20.7%, 26.7%, and 33.3%, respectively. Epithelial cell colonization was detected in the cell-culture samples taken from the control group but not in the samples taken from the CSE group. We could not reproduce the cells or cell debris obtained during the CSE interventions in vivo, which can be explained by a possible structural deformation of cells or the inadequacy of the amount of cells that were transferred.

  1. Qualitatively monitoring binding and expression of the transcription factor Sp1 as a useful tool to evaluate the reliability of primary cultured epithelial stem cells in tissue reconstruction.

    PubMed

    Gaudreault, Manon; Larouche, Danielle; Germain, Lucie; Guérin, Sylvain L

    2013-01-01

    Electrophoretic mobility shift assay and Western blot are simple, efficient, and rapid methods for the study of DNA-protein interactions and expression, respectively. Primary cultures and subcultures of epithelial cells are widely used for the production of tissue-engineered substitutes and are gaining popularity as a model for gene expression studies. The preservation of stem-cells through the culture process is essential to produce high quality substitutes. However as such cells are passaged in culture, they often lose their ability to proliferate, a process likely to be determined by the altered expression of nuclear-located transcription factors such as Sp1, whose expression has been documented to be required for cell adhesion, migration, and differentiation. Our recent studies demonstrated that reconstructed tissues exhibiting poor histological and structural characteristics are also those that were produced with epithelial cells in which expression and DNA binding of Sp1 was reduced in vitro. Therefore, monitoring both the expression and DNA binding of this transcription factor in human skin and corneal epithelial cells might prove a particularly useful tool for selecting which cells are to be used for tissue reconstruction.

  2. COX-2 (PTGS2) gene methylation in epithelial, subepithelial lymphocyte and stromal tissue compartments in a spectrum of esophageal squamous neoplasia.

    PubMed

    Dawsey, Sonja P; Roth, Mark J; Adams, Lisa; Hu, Nan; Wang, Quan-Hong; Taylor, Philip R; Woodson, Karen

    2008-01-01

    Previous studies have shown important effects of stromal elements in carcinogenesis. To explore the tumor-stromal relationship in esophageal neoplasia, we examined methylation of COX-2 (PTGS2), a gene etiologically associated with the development of gastrointestinal cancers, in adjacent foci of epithelium, subepithelial lymphocytes and non-lymphocytic stromal cells found in sections of normal squamous epithelium, squamous dysplasia and invasive esophageal squamous cell carcinoma. Adjacent foci of epithelium, subepithelial lymphocytic aggregates and non-lymphocytic stromal tissues were laser microdissected from six fully embedded, ethanol fixed, esophagectomy samples from Shanxi, China, a high-risk region for esophageal cancer. Promoter CpG site-specific hypermethylation status of COX-2 was determined using real-time methylation-specific PCR (qMS-PCR) based on Taqman Chemistry. The methylation status of a subset of samples was confirmed by pyrosequencing. Forty-nine microdissected foci were analyzed. COX-2 gene methylation was significantly more common in subepithelial lymphocytes (12/16 (75% of all foci)) than in epithelial foci (3/16 (19%)) or foci of non-lymphocytic stromal tissues (3/17 (18%)) (Fisher's exact p=0.05). Two of three epithelial samples and all three stromal samples that showed COX-2 methylation were adjacent to foci of methylated subepithelial lymphocytes. Pyrosequencing confirmed the methylation status in a subset of samples. In these esophageal cancer patients, COX-2 gene methylation was more common in subepithelial lymphocytes than in adjacent epithelial or stromal cells in both grades of dysplasia and in foci of invasive cancer. These findings raise the possibility that methylation of subepithelial lymphocytes may be important for tumorigenesis. Future studies of gene methylation should consider separate evaluation of epithelial and non-epithelial cell populations.

  3. A phloem-limited fijivirus induces the formation of neoplastic phloem tissues that house virus multiplication in the host plant

    PubMed Central

    Shen, Jiangfeng; Chen, Xian; Chen, Jianping; Sun, Liying

    2016-01-01

    A number of phloem-limited viruses induce the development of tumours (enations) in the veins of host plants, but the relevance of tumour induction to the life cycle of those viruses is unclear. In this study, we performed molecular and structural analyses of tumours induced by rice black-streaked dwarf virus (RBSDV, genus Fijivirus) infection in maize plants. The transcript level of the maize cdc2 gene, which regulates the cell cycle, was highly elevated in tumour tissues. Two-dimensional electrophoresis identified 25 cellular proteins with altered accumulation in the tumour tissues. These proteins are involved in various metabolic pathways, including photosynthesis, redox, energy pathways and amino acid synthesis. Histological analysis indicated that the tumours predominantly originated from hyperplastic growth of phloem, but those neoplastic tissues have irregular structures and cell arrangements. Immunodetection assays and electron microscopy observations indicated that in the shoots, RBSDV is confined to phloem and tumour regions and that virus multiplication actively occurs in the tumour tissue, as indicated by the high accumulation of non-structural proteins and formation of viroplasms in the tumour cells. Thus, the induction of tumours by RBSDV infection provides a larger environment that is favourable for virus propagation in the host plant. PMID:27432466

  4. Tissue types (image)

    MedlinePlus

    There are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue supports other tissues and binds them together (bone, blood, and lymph tissues). ...

  5. Aire Downregulation Is Associated with Changes in the Posttranscriptional Control of Peripheral Tissue Antigens in Medullary Thymic Epithelial Cells

    PubMed Central

    Oliveira, Ernna H.; Macedo, Claudia; Collares, Cristhianna V.; Freitas, Ana Carolina; Donate, Paula Barbim; Sakamoto-Hojo, Elza T.; Donadi, Eduardo A.; Passos, Geraldo A.

    2016-01-01

    Autoimmune regulator (Aire) is a transcriptional regulator of peripheral tissue antigens (PTAs) and microRNAs (miRNAs) in medullary thymic epithelial cells (mTECs). In this study, we tested the hypothesis that Aire also played a role as an upstream posttranscriptional controller in these cells and that variation in its expression might be associated with changes in the interactions between miRNAs and the mRNAs encoding PTAs. We demonstrated that downregulation of Aire in vivo in the thymuses of BALB/c mice imbalanced the large-scale expression of these two RNA species and consequently their interactions. The expression profiles of a large set of mTEC miRNAs and mRNAs isolated from the thymuses of mice subjected (or not) to small-interfering-induced Aire gene knockdown revealed that 87 miRNAs and 4,558 mRNAs were differentially expressed. The reconstruction of the miRNA–mRNA interaction networks demonstrated that interactions between these RNAs were under Aire influence and therefore changed when this gene was downregulated. Prior to Aire-knockdown, only members of the miR-let-7 family interacted with a set of PTA mRNAs. Under Aire-knockdown conditions, a larger set of miRNA families and their members established this type of interaction. Notably, no previously described Aire-dependent PTA interacted with the miRNAs, indicating that these PTAs were somehow refractory. The miRNA–mRNA interactions were validated by calculating the minimal free energy of the pairings between the miRNA seed regions and the mRNA 3′ UTRs and within the cellular milieu using the luciferase reporter gene assay. These results suggest the existence of a link between transcriptional and posttranscriptional control because Aire downregulation alters the miRNA–mRNA network controlling PTAs in mTEC cells. PMID:27933063

  6. Aire Downregulation Is Associated with Changes in the Posttranscriptional Control of Peripheral Tissue Antigens in Medullary Thymic Epithelial Cells.

    PubMed

    Oliveira, Ernna H; Macedo, Claudia; Collares, Cristhianna V; Freitas, Ana Carolina; Donate, Paula Barbim; Sakamoto-Hojo, Elza T; Donadi, Eduardo A; Passos, Geraldo A

    2016-01-01

    Autoimmune regulator (Aire) is a transcriptional regulator of peripheral tissue antigens (PTAs) and microRNAs (miRNAs) in medullary thymic epithelial cells (mTECs). In this study, we tested the hypothesis that Aire also played a role as an upstream posttranscriptional controller in these cells and that variation in its expression might be associated with changes in the interactions between miRNAs and the mRNAs encoding PTAs. We demonstrated that downregulation of Aire in vivo in the thymuses of BALB/c mice imbalanced the large-scale expression of these two RNA species and consequently their interactions. The expression profiles of a large set of mTEC miRNAs and mRNAs isolated from the thymuses of mice subjected (or not) to small-interfering-induced Aire gene knockdown revealed that 87 miRNAs and 4,558 mRNAs were differentially expressed. The reconstruction of the miRNA-mRNA interaction networks demonstrated that interactions between these RNAs were under Aire influence and therefore changed when this gene was downregulated. Prior to Aire-knockdown, only members of the miR-let-7 family interacted with a set of PTA mRNAs. Under Aire-knockdown conditions, a larger set of miRNA families and their members established this type of interaction. Notably, no previously described Aire-dependent PTA interacted with the miRNAs, indicating that these PTAs were somehow refractory. The miRNA-mRNA interactions were validated by calculating the minimal free energy of the pairings between the miRNA seed regions and the mRNA 3' UTRs and within the cellular milieu using the luciferase reporter gene assay. These results suggest the existence of a link between transcriptional and posttranscriptional control because Aire downregulation alters the miRNA-mRNA network controlling PTAs in mTEC cells.

  7. Differentiated epidermal outgrowths in the planarian Dugesia gonocephala: a model for studying cell renewal and patterning in single-layered epithelial tissue.

    PubMed

    Chandebois, R

    1985-01-01

    Large deep wounds on the ventral side of a flatworm (Planaria) will not heal. Instead, the damage to the parenchyma in the wound's roof will result in a differentiated swelling in the dorsal epidermis, above the wound which will eventually disappear with the disintegration of the underlying damaged tissue and a ventrodorsal hole appears in place of the wound. The dorsal epidermal outgrowth is formed by a number of excrescences, the development of which involves four successive stages. Their analysis suggests that epidermal cells are continuously produced by their own stem cells which remain unnoticed because their nuclei are hardly stainable. The daughter cells differentiate without information from either the underlying tissues or the basal epithelial membrane. During the first stage of this differentiation the cells become ciliated and motile, with some embryonic features. They then produce rhabdites and take up a columnar shape as they may become attached to the basal membrane. After wound setting the production of epidermal cells increases and the overcrowding of the basal membrane results in (1) detachment of stem cells and motile ciliated cells from the basal tissues, i.e. outgrowths; (2) stretching of columnar cells at the base of the outgrowths. When in the process of tissue disintegration the basal membrane of the epithelium also disappears, the cells remain in a single-layered epithelial configuration and retain their original polarity. These results are at variance with the generally accepted hypothesis that, in planarians, epidermal cells originate from the parenchyma and the epidermis is not an autonomous tissue.

  8. Upregulated epidermal growth factor receptor expression following near-infrared irradiation simulating solar radiation in a three-dimensional reconstructed human corneal epithelial tissue culture model.

    PubMed

    Tanaka, Yohei; Nakayama, Jun

    2016-01-01

    Humans are increasingly exposed to near-infrared (NIR) radiation from both natural (eg, solar) and artificial (eg, electrical appliances) sources. Although the biological effects of sun and ultraviolet (UV) exposure have been extensively investigated, the biological effect of NIR radiation is still unclear. We previously reported that NIR as well as UV induces photoaging and standard UV-blocking materials, such as sunglasses, do not sufficiently block NIR. The objective of this study was to investigate changes in gene expression in three-dimensional reconstructed corneal epithelial tissue culture exposed to broad-spectrum NIR irradiation to simulate solar NIR radiation that reaches human tissues. DNA microarray and quantitative real-time polymerase chain reaction analysis were used to assess gene expression levels in a three-dimensional reconstructed corneal epithelial model composed of normal human corneal epithelial cells exposed to water-filtered broad-spectrum NIR irradiation with a contact cooling (20°C). The water-filter allowed 1,000-1,800 nm wavelengths and excluded 1,400-1,500 nm wavelengths. A DNA microarray with >62,000 different probes showed 25 and 150 genes that were up- or downregulated by at least fourfold and twofold, respectively, after NIR irradiation. In particular, epidermal growth factor receptor (EGFR) was upregulated by 19.4-fold relative to control cells. Quantitative real-time polymerase chain reaction analysis revealed that two variants of EGFR in human corneal epithelial tissue were also significantly upregulated after five rounds of 10 J/cm(2) irradiation (P<0.05). We found that NIR irradiation induced the upregulated expression of EGFR in human corneal cells. Since over half of the solar energy reaching the Earth is in the NIR region, which cannot be adequately blocked by eyewear and thus can induce eye damage with intensive or long-term exposure, protection from both UV and NIR radiation may prevent changes in gene expression and in

  9. ADAM28 is expressed by epithelial cells in human normal tissues and protects from C1q-induced cell death.

    PubMed

    Miyamae, Yuka; Mochizuki, Satsuki; Shimoda, Masayuki; Ohara, Kentaro; Abe, Hitoshi; Yamashita, Shuji; Kazuno, Saiko; Ohtsuka, Takashi; Ochiai, Hiroki; Kitagawa, Yuko; Okada, Yasunori

    2016-05-01

    ADAM28 (disintegrin and metalloproteinase 28), which was originally reported to be lymphocyte-specific, is over-expressed by carcinoma cells and plays a key role in cell proliferation and progression in human lung and breast carcinomas. We studied ADAM28 expression in human normal tissues and examined its biological function. By using antibodies specific to ADAM28, ADAM28 was immunolocalized mainly to epithelial cells in several tissues, including epididymis, bronchus and stomach, whereas lymphocytes in lymph nodes and spleen were negligibly immunostained. RT-PCR, immunoblotting and ELISA analyses confirmed the expression in these tissues, and low or negligible expression by lymphocytes was found in the lymph node and spleen. C1q was identified as a candidate ADAM28-binding protein from a human lung cDNA library by yeast two-hybrid system, and specific binding was demonstrated by binding assays, immunoprecipitation and surface plasmon resonance. C1q treatment of normal bronchial epithelial BEAS-2B and NHBE cells, both of which showed low-level expression of ADAM28, caused apoptosis through activation of p38 and caspase-3, and cell death with autophagy through accumulation of LC3-II and autophagosomes, respectively. C1q-induced cell death was attenuated by treatment of the cells with antibodies against the C1q receptor gC1qR/p33 or cC1qR/calreticulin. Treatment of C1q with recombinant ADAM28 prior to addition to culture media reduced C1q-induced cell death, and knockdown of ADAM28 using siRNAs increased cell death. These data demonstrate that ADAM28 is expressed by epithelial cells of several normal organs, and suggest that ADAM28 plays a role in cell survival by suppression of C1q-induced cytotoxicity in bronchial epithelial cells.

  10. Effects of a Mediterranean Diet Intervention on Anti- and Pro-Inflammatory Eicosanoids, Epithelial Proliferation, and Nuclear Morphology in Biopsies of Normal Colon Tissue.

    PubMed

    Djuric, Zora; Turgeon, D Kim; Ren, Jianwei; Neilson, Andrew; Plegue, Missy; Waters, Ian G; Chan, Alexander; Askew, Leah M; Ruffin, Mack T; Sen, Ananda; Brenner, Dean E

    2015-01-01

    This randomized trial evaluated the effects of intervention with either a Healthy Eating or a Mediterranean diet on colon biomarkers in 120 healthy individuals at increased colon cancer risk. The hypothesis was that eicosanoids and markers of proliferation would be favorably affected by the Mediterranean diet. Colon epithelial biopsy tissues and blood samples were obtained at baseline and after 6 mo of intervention. Colonic eicosanoid concentrations were evaluated by HPLC-MS-MS, and measures of epithelial proliferation and nuclear morphology were evaluated by image analysis of biopsy sections. There was little change in proinflammatory eicosanoids and in plasma cytokine concentrations with either dietary intervention. There was, however, a 50% increase in colonic prostaglandin E3 (PGE3), which is formed from eicosapentanoic acid, in the Mediterranean arm. Unlike PGE2, PGE3, was not significantly affected by regular use of non-steroidal anti-inflammatory drugs at baseline, and normal weight subjects had significantly higher colon PGE3 than overweight or obese subjects. Increased proliferation in the colon at baseline, by Ki67 labeling, was associated with morphological features that defined smaller nuclei in the epithelial cells, lower colon leukotriene concentrations and higher plasma cytokine concentrations. Dietary intervention had little effect on measures of epithelial proliferation or of nuclear morphology. The increase in PGE3 with a Mediterranean diet indicates that in normal colon, diet might affect protective pathways to a greater extent than proinflammatory and proliferative pathways. Hence, biomarkers from cancer models might not be relevant in a true prevention setting.

  11. Abiotic Versus Biotic Pathogens: Replicative Growth in Host Tissues Key to Discriminating Between Biotoxic Injury and Active Pathogenesis

    NASA Technical Reports Server (NTRS)

    Schuerger, Andrew C.; Ming, Douglas W.; Golden, D. C.

    2012-01-01

    Life can be defined as a self-sustaining chemical system capable of undergoing Darwinian evolution; a self-bounded, self-replicating, and self-perpetuating entity [1]. This definition should hold for terrestrial as well as extraterrestrial life-forms. Although, it is reasonable to expect that a Mars life-form would be more adaptable to Mars-like conditions than to Earth-like environments, it remains possible that negative ecological or host interactions might occur if Mars microbiota were to be inadvertently released into the terrestrial environment. A biogenic infectious agent can be defined as a self-sustaining chemical system capable of undergoing Darwinian evolution and derives its sustenance from a living cell or from the by-products of cell death. Disease can be de-fined as the detrimental alteration of one or more ordered metabolic processes in a living host caused by the continued irritation of a primary causal factor or factors; disease is a dynamic process [2]. In contrast, an injury is due to an instantaneous event; injury is not a dynamic process [2]. A causal agent of disease is defined as a pathogen, and can be either abiotic or biotic in nature. Diseases incited by biotic pathogens are the exceptions, not the norms, in terrestrial host-microbe interactions. Disease induction in a plant host can be conceptually characterized using the Disease Triangle (Fig. 1) in which disease occurs only when all host, pathogen, and environ-mental factors that contribute to the development of disease are within conducive ranges for a necessary minimum period of time. For example, plant infection and disease caused by the wheat leaf rust fungus, Puccinia recondita, occur only if virulent spores adhere to genetically susceptible host tissues for at least 4-6 hours under favorable conditions of temperature and moisture [3]. As long as one or more conditions required for disease initiation are not available, disease symptoms will not develop.

  12. Tissue-Specific Expression Patterns of MicroRNA during Acute Graft-versus-Host Disease in the Rat

    PubMed Central

    Jalapothu, Dasaradha; Boieri, Margherita; Crossland, Rachel E.; Shah, Pranali; Butt, Isha A.; Norden, Jean; Dressel, Ralf; Dickinson, Anne M.; Inngjerdingen, Marit

    2016-01-01

    MicroRNAs (miRNA) have emerged as central regulators of diverse biological processes and contribute to driving pathology in several diseases. Acute graft-versus-host disease (aGvHD) represents a major complication after allogeneic hematopoietic stem cell transplantation, caused by alloreactive donor T cells attacking host tissues leading to inflammation and tissue destruction. Changes in miRNA expression patterns occur during aGvHD, and we hypothesized that we could identify miRNA signatures in target tissues of aGvHD that may potentially help understand the underlying molecular pathology of the disease. We utilized a rat model of aGvHD with transplantation of fully MHC-mismatched T cell depleted bone marrow, followed by infusion of donor T cells. The expression pattern of 423 rat miRNAs was investigated in skin, gut, and lung tissues and intestinal T cells with the NanoString hybridization platform, in combination with validation by quantitative PCR. MHC-matched transplanted rats were included as controls. In the skin, upregulation of miR-34b and downregulation of miR-326 was observed, while in the intestines, we detected downregulation of miR-743b and a trend toward downregulation of miR-345-5p. Thus, tissue-specific expression patterns of miRNAs were observed. Neither miR-326 nor miR-743b has previously been associated with aGvHD. Moreover, we identified upregulation of miR-146a and miR-155 in skin tissue of rats suffering from aGvHD. Analysis of intestinal T cells indicated 23 miRNAs differentially regulated between aGvHD and controls. Two of these miRNAs were differentially expressed either in skin (miR-326) or in intestinal (miR-345-5p) tissue. Comparison of intestinal and peripheral blood T cells indicated common dysregulated expression of miR-99a, miR-223, miR-326, and miR-345-5p. Analysis of predicted gene targets for these miRNAs indicated potential targeting of an inflammatory network both in skin and in the intestines that may further regulate

  13. Organic tissues, graphite, and hydrocarbons in host rocks of the Rum Jungle Uranium Field, northern Australia

    USGS Publications Warehouse

    Foster, C.B.; Robbins, E.I.; Bone, Y.

    1990-01-01

    The Rum Jungle Uranium field consists of at least six early Proterozoic deposits that have been mined either for uranium and/or the associated base and precious metals. Organic matter in the host rocks of the Whites Formation and Coomalie Dolomite is now predominantly graphite, consistent with the metamorphic history of these rocks. For nine samples, the mean total organic carbon content is high (3.9 wt%) and ranged from 0.33 to 10.44 wt%. Palynological extracts from the host rocks include black, filamentous, stellate (Eoastrion-like), and spherical morphotypes, which are typical of early Proterozoic microbiota. The colour, abundance, and shapes of these morphotypes reflect the thermal history, organic richness, and probable lacustrine biofacies of the host rocks. Routine analysis of rock thin sections and of palynological residues shows that mineral grains in some of the host rocks are coated with graphitized organic matter. The grain coating is presumed to result from ultimate thermal degradation of a petroleum phase that existed prior to metamorphism. Hydrocarbons are, however, still present in fluid inclusions within carbonates of the Coomalie Dolomite and lower Whites Formation. The fluid inclusions fluoresce dull orange in blue-light excitation and their hydrocarbon content is confirmed by gas chromatography of whole-rock extracts. Preliminary analysis of the oil suggests that it is migrated, and because it has escaped graphitization through metamorphism it is probably not of early Proterozoic age. The presence of live oil is consistent with fluid inclusion data that suggest subsequent, low-temperature brine migration through the rocks. The present observations support earlier suggestions that organic matter in the host formations trapped uranium to form protore. Subsequent fluid migrations probably brought additional uranium and other metals to these formations, and the organic matter provided a reducing environment for entrapment. ?? 1990.

  14. Processing window for femtosecond laser microsurgery and fluorescence imaging of an arterial tissue hosted in a microfluidic chip

    NASA Astrophysics Data System (ADS)

    Karimelahi, Samira; Li, Jianzhao; Herman, Peter R.

    2016-02-01

    We study the exposure limitations of femtosecond laser microsurgery and multiphoton imaging in a microfluidic chip environment, assessing damage thresholds at various interfaces as well as interference from bubble formation in the hosting solution. Both heat accumulation and incubation effects from multipulse laser exposures at 1-MHz repetition rate were evaluated. For demonstration, three microsurgery approaches of laser scribing, percussion drilling and trepanning were applied to arterial walls loaded in vitro in a lab-on-a-chip device. We report that deleterious effects from interface damage and microbubble formation can be avoided to offer laser processing windows for damage-free fluorescence imaging and precise microsurgery of live tissue hosted inside small microfluidic chambers.

  15. Teratocarcinomas Arising from Allogeneic Induced Pluripotent Stem Cell-Derived Cardiac Tissue Constructs Provoked Host Immune Rejection in Mice

    PubMed Central

    Kawamura, Ai; Miyagawa, Shigeru; Fukushima, Satsuki; Kawamura, Takuji; Kashiyama, Noriyuki; Ito, Emiko; Watabe, Tadashi; Masuda, Shigeo; Toda, Koichi; Hatazawa, Jun; Morii, Eiichi; Sawa, Yoshiki

    2016-01-01

    Transplantation of induced pluripotent stem cell-derived cardiac tissue constructs is a promising regenerative treatment for cardiac failure: however, its tumourigenic potential is concerning. We hypothesised that the tumourigenic potential may be eliminated by the host immune response after allogeneic cell transplantation. Scaffold-free iPSC-derived cardaic tissue sheets of C57BL/6 mouse origin were transplanted into the cardiac surface of syngeneic C57BL/6 mice and allogeneic BALB/c mice with or without tacrolimus injection. Syngeneic mice and tacrolimus-injected immunosuppressed allogeneic mice formed teratocarcinomas with identical phenotypes, characteristic, and time courses, as assessed by imaging tools including 18F-fluorodeoxyglucose-positron emission tomography. In contrast, temporarily immunosuppressed allogeneic mice, following cessation of tacrolimus injection displayed diminished progression of the teratocarcinoma, accompanied by an accumulation of CD4/CD8-positive T cells, and finally achieved complete elimination of the teratocarcinoma. Our results indicated that malignant teratocarcinomas arising from induced pluripotent stem cell-derived cardiac tissue constructs provoked T cell-related host immune rejection to arrest tumour growth in murine allogeneic transplantation models. PMID:26763872

  16. Blood flow responses to mild-intensity exercise in ectopic vs. orthotopic prostate tumors; dependence upon host tissue hemodynamics and vascular reactivity.

    PubMed

    Garcia, Emmanuel; Becker, Veronika G C; McCullough, Danielle J; Stabley, John N; Gittemeier, Elizabeth M; Opoku-Acheampong, Alexander B; Sieman, Dietmar W; Behnke, Bradley J

    2016-07-01

    Given the critical role of tumor O2 delivery in patient prognosis and the rise in preclinical exercise oncology studies, we investigated tumor and host tissue blood flow at rest and during exercise as well as vascular reactivity using a rat prostate cancer model grown in two transplantation sites. In male COP/CrCrl rats, blood flow (via radiolabeled microspheres) to prostate tumors [R3327-MatLyLu cells injected in the left flank (ectopic) or ventral prostate (orthotopic)] and host tissue was measured at rest and during a bout of mild-intensity exercise. α-Adrenergic vasoconstriction to norepinephrine (NE: 10(-9) to 10(-4) M) was determined in arterioles perforating the tumors and host tissue. To determine host tissue exercise hyperemia in healthy tissue, a sham-operated group was included. Blood flow was lower at rest and during exercise in ectopic tumors and host tissue (subcutaneous adipose) vs. the orthotopic tumor and host tissue (prostate). During exercise, blood flow to the ectopic tumor significantly decreased by 25 ± 5% (SE), whereas flow to the orthotopic tumor increased by 181 ± 30%. Maximal vasoconstriction to NE was not different between arterioles from either tumor location. However, there was a significantly higher peak vasoconstriction to NE in subcutaneous adipose arterioles (92 ± 7%) vs. prostate arterioles (55 ± 7%). Establishment of the tumor did not alter host tissue blood flow from either location at rest or during exercise. These data demonstrate that blood flow in tumors is dependent on host tissue hemodynamics and that the location of the tumor may critically affect how exercise impacts the tumor microenvironment and treatment outcomes.

  17. A worm of one's own: how helminths modulate host adipose tissue function and metabolism.

    PubMed

    Guigas, Bruno; Molofsky, Ari B

    2015-09-01

    Parasitic helminths have coexisted with human beings throughout time. Success in eradicating helminths has limited helminth-induced morbidity and mortality but is also correlated with increasing rates of 'western' diseases, including metabolic syndrome and type 2 diabetes. Recent studies in mice describe how type 2 immune cells, traditionally associated with helminth infection, maintain adipose tissue homeostasis and promote adipose tissue beiging, protecting against obesity and metabolic dysfunction. Here, we review these studies and discuss how helminths and helminth-derived molecules may modulate these physiologic pathways to improve metabolic functions in specific tissues, such as adipose and liver, as well as at the whole-organism level.

  18. Depletion of host CCR7(+) dendritic cells prevented donor T cell tissue tropism in anti-CD3-conditioned recipients.

    PubMed

    He, Wei; Racine, Jeremy J; Johnston, Heather F; Li, Xiaofan; Li, Nainong; Cassady, Kaniel; Liu, Can; Deng, Ruishu; Martin, Paul; Forman, Stephen; Zeng, Defu

    2014-07-01

    We reported previously that anti-CD3 mAb treatment before hematopoietic cell transplantation (HCT) prevented graft-versus-host disease (GVHD) and preserved graft-versus-leukemia (GVL) effects in mice. These effects were associated with downregulated donor T cell expression of tissue-specific homing and chemokine receptors, marked reduction of donor T cell migration into GVHD target tissues, and deletion of CD103(+) dendritic cells (DCs) in mesenteric lymph nodes (MLN). MLN CD103(+) DCs and peripheral lymph node (PLN) DCs include CCR7(+) and CCR7(-) subsets, but the role of these DC subsets in regulating donor T cell expression of homing and chemokine receptors remain unclear. Here, we show that recipient CCR7(+), but not CCR7(-), DCs in MLN induced donor T cell expression of gut-specific homing and chemokine receptors in a retinoid acid-dependent manner. CCR7 regulated activated DC migration from tissue to draining lymph node, but it was not required for the ability of DCs to induce donor T cell expression of tissue-specific homing and chemokine receptors. Finally, anti-CD3 treatment depleted CCR7(+) but not CCR7(-) DCs by inducing sequential expansion and apoptosis of CCR7(+) DCs in MLN and PLN. Apoptosis of CCR7(+) DCs was associated with DC upregulation of Fas expression and natural killer cell but not T, B, or dendritic cell upregulation of FasL expression in the lymph nodes. These results suggest that depletion of CCR7(+) host-type DCs, with subsequent inhibition of donor T cell migration into GVHD target tissues, can be an effective approach in prevention of acute GVHD and preservation of GVL effects.

  19. Polarity in Mammalian Epithelial Morphogenesis

    PubMed Central

    Roignot, Julie; Peng, Xiao; Mostov, Keith

    2013-01-01

    Cell polarity is fundamental for the architecture and function of epithelial tissues. Epithelial polarization requires the intervention of several fundamental cell processes, whose integration in space and time is only starting to be elucidated. To understand what governs the building of epithelial tissues during development, it is essential to consider the polarization process in the context of the whole tissue. To this end, the development of three-dimensional organotypic cell culture models has brought new insights into the mechanisms underlying the establishment and maintenance of higher-order epithelial tissue architecture, and in the dynamic remodeling of cell polarity that often occurs during development of epithelial organs. Here we discuss some important aspects of mammalian epithelial morphogenesis, from the establishment of cell polarity to epithelial tissue generation. PMID:23378592

  20. A Kinome RNAi Screen in Drosophila Identifies Novel Genes Interacting with Lgl, aPKC, and Crb Cell Polarity Genes in Epithelial Tissues

    PubMed Central

    Parsons, Linda M.; Grzeschik, Nicola A.; Amaratunga, Kasun; Burke, Peter; Quinn, Leonie M.; Richardson, Helena E.

    2017-01-01

    In both Drosophila melanogaster and mammalian systems, epithelial structure and underlying cell polarity are essential for proper tissue morphogenesis and organ growth. Cell polarity interfaces with multiple cellular processes that are regulated by the phosphorylation status of large protein networks. To gain insight into the molecular mechanisms that coordinate cell polarity with tissue growth, we screened a boutique collection of RNAi stocks targeting the kinome for their capacity to modify Drosophila “cell polarity” eye and wing phenotypes. Initially, we identified kinase or phosphatase genes whose depletion modified adult eye phenotypes associated with the manipulation of cell polarity complexes (via overexpression of Crb or aPKC). We next conducted a secondary screen to test whether these cell polarity modifiers altered tissue overgrowth associated with depletion of Lgl in the wing. These screens identified Hippo, Jun kinase (JNK), and Notch signaling pathways, previously linked to cell polarity regulation of tissue growth. Furthermore, novel pathways not previously connected to cell polarity regulation of tissue growth were identified, including Wingless (Wg/Wnt), Ras, and lipid/Phospho-inositol-3-kinase (PI3K) signaling pathways. Additionally, we demonstrated that the “nutrient sensing” kinases Salt Inducible Kinase 2 and 3 (SIK2 and 3) are potent modifiers of cell polarity phenotypes and regulators of tissue growth. Overall, our screen has revealed novel cell polarity-interacting kinases and phosphatases that affect tissue growth, providing a platform for investigating molecular mechanisms coordinating cell polarity and tissue growth during development. PMID:28611255

  1. A Kinome RNAi Screen in Drosophila Identifies Novel Genes Interacting with Lgl, aPKC, and Crb Cell Polarity Genes in Epithelial Tissues.

    PubMed

    Parsons, Linda M; Grzeschik, Nicola A; Amaratunga, Kasun; Burke, Peter; Quinn, Leonie M; Richardson, Helena E

    2017-08-07

    In both Drosophila melanogaster and mammalian systems, epithelial structure and underlying cell polarity are essential for proper tissue morphogenesis and organ growth. Cell polarity interfaces with multiple cellular processes that are regulated by the phosphorylation status of large protein networks. To gain insight into the molecular mechanisms that coordinate cell polarity with tissue growth, we screened a boutique collection of RNAi stocks targeting the kinome for their capacity to modify Drosophila "cell polarity" eye and wing phenotypes. Initially, we identified kinase or phosphatase genes whose depletion modified adult eye phenotypes associated with the manipulation of cell polarity complexes (via overexpression of Crb or aPKC). We next conducted a secondary screen to test whether these cell polarity modifiers altered tissue overgrowth associated with depletion of Lgl in the wing. These screens identified Hippo, Jun kinase (JNK), and Notch signaling pathways, previously linked to cell polarity regulation of tissue growth. Furthermore, novel pathways not previously connected to cell polarity regulation of tissue growth were identified, including Wingless (Wg/Wnt), Ras, and lipid/Phospho-inositol-3-kinase (PI3K) signaling pathways. Additionally, we demonstrated that the "nutrient sensing" kinases Salt Inducible Kinase 2 and 3 (SIK2 and 3) are potent modifiers of cell polarity phenotypes and regulators of tissue growth. Overall, our screen has revealed novel cell polarity-interacting kinases and phosphatases that affect tissue growth, providing a platform for investigating molecular mechanisms coordinating cell polarity and tissue growth during development. Copyright © 2017 Parsons et al.

  2. Epithelialization Over a Scaffold of Antibiotic-Impregnated PMMA Beads: A Salvage Technique for Open Tibial Fractures with Bone and Soft Tissue Loss When all Else Fails

    PubMed Central

    Masrouha, Karim Z.; El-Bitar, Youssef; Najjar, Marc; Saghieh, Said

    2016-01-01

    The management of soft tissue defects in tibial fractures is essential for limb preservation. Current techniques are not without complications and may lead to poor functional outcomes. A salvage method is described using three illustrative cases whereby a combination of flaps and antibiotic-impregnated polymethylmethacrylate beads are employed to fill the bony defect, fight the infection, and provide a surface for epithelial regeneration and secondary wound closure. This was performed after the partial failure of all other options. All patients were fully ambulatory with no clinical, radiographic or laboratory sign of infection at their most recent follow-up. Although our findings are encouraging, this is the first report of epithelialization of the skin on a polymethylmethacrylate scaffold. Further studies investigating the use of this technique are warranted. PMID:27517073

  3. Host-derived diagnostic markers related to soft tissue destruction and bone degradation in periodontitis.

    PubMed

    Buduneli, Nurcan; Kinane, Denis F

    2011-03-01

    A major challenge in clinical periodontics is to find a reliable molecular marker of periodontal tissue destruction with high sensitivity, specificity and utility. The aim of this systematic review is to evaluate available literature on 'the utility of molecular markers of soft and hard periodontal tissue destruction'. Based on the focused question, 'What is the utility of molecular markers of soft and hard periodontal tissue destruction', an electronic and manual search was conducted for human studies presenting clinical data for the potential of molecular markers of tissue destruction in biofluids; gingival crevicular fluid (GCF), saliva, and serum. Papers fulfilling the inclusion criteria were selected. All relevant data from the selected papers were extracted and recorded in separate tables for molecules in GCF, saliva, and serum. Within the defined limits of the Problem/Population, Intervention, Comparison, Outcome, the present analysis reveals that (a) no single or combination of markers exists that can disclose periodontal tissue destruction adequately; (b) while the most fruitful source of biomarkers for periodontal destruction appears to be in molecules tightly related to bone and soft tissue destruction, this remains to be objectively demonstrated. Currently, clinical measurements are still the most reliable. © 2011 John Wiley & Sons A/S.

  4. The use of laser microdissection in the identification of suitable reference genes for normalization of quantitative real-time PCR in human FFPE epithelial ovarian tissue samples.

    PubMed

    Cai, Jing; Li, Tao; Huang, Bangxing; Cheng, Henghui; Ding, Hui; Dong, Weihong; Xiao, Man; Liu, Ling; Wang, Zehua

    2014-01-01

    Quantitative real-time PCR (qPCR) is a powerful and reproducible method of gene expression analysis in which expression levels are quantified by normalization against reference genes. Therefore, to investigate the potential biomarkers and therapeutic targets for epithelial ovarian cancer by qPCR, it is critical to identify stable reference genes. In this study, twelve housekeeping genes (ACTB, GAPDH, 18S rRNA, GUSB, PPIA, PBGD, PUM1, TBP, HRPT1, RPLP0, RPL13A, and B2M) were analyzed in 50 ovarian samples from normal, benign, borderline, and malignant tissues. For reliable results, laser microdissection (LMD), an effective technique used to prepare homogeneous starting material, was utilized to precisely excise target tissues or cells. One-way analysis of variance (ANOVA) and nonparametric (Kruskal-Wallis) tests were used to compare the expression differences. NormFinder and geNorm software were employed to further validate the suitability and stability of the candidate genes. Results showed that epithelial cells occupied a small percentage of the normal ovary indeed. The expression of ACTB, PPIA, RPL13A, RPLP0, and TBP were stable independent of the disease progression. In addition, NormFinder and geNorm identified the most stable combination (ACTB, PPIA, RPLP0, and TBP) and the relatively unstable reference gene GAPDH from the twelve commonly used housekeeping genes. Our results highlight the use of homogeneous ovarian tissues and multiple-reference normalization strategy, e.g. the combination of ACTB, PPIA, RPLP0, and TBP, for qPCR in epithelial ovarian tissues, whereas GAPDH, the most commonly used reference gene, is not recommended, especially as a single reference gene.

  5. Host tissue response by the expression of collagen to cyanoacrylate adhesives used in implant fixation for abdominal hernia repair.

    PubMed

    Pascual, Gemma; Rodríguez, Marta; Pérez-Köhler, Bárbara; Mesa-Ciller, Claudia; Fernández-Gutiérrez, Mar; San Román, Julio; Bellón, Juan M

    2017-04-01

    The less traumatic use of surgical adhesives rather than sutures for mesh fixation in hernia repair has started to gain popularity because they induce less host tissue damage and provoke less postoperative pain. This study examines the host tissue response to a new cyanoacrylate (CA) adhesive (n-octyl, OCA). Partial defects (3 × 5 cm) created in the rabbit anterior abdominal wall were repaired by mesh fixation using OCA, Glubran2(®)(n-butyl-CA), Ifabond(®)(n-hexyl-CA) or sutures. Samples were obtained at 14/90 days for morphology, collagens qRT-PCR/immunofluorescence and biomechanical studies. All meshes were successfully fixed. Seroma was detected mainly in the Glubran group at 14 days. Meshes fixed using all methods showed good host tissue incorporation. No signs of degradation of any of the adhesives were observed. At 14 days, collagen 1 and 3 mRNA expression levels were greater in the suture and OCA groups, and lower in Ifabond, with levels varying significantly in the latter group with respect to the others. By 90 days, expression levels had fallen in all groups, except for collagen 3 mRNA in Ifabond. Collagen I and III protein expression was marked in the suture and OCA groups at 90 days, but lower in Ifabond at both time points. Tensile strengths were similar across groups. Our findings indicate the similar behavior of the adhesives to sutures in terms of good tissue incorporation of the meshes and optimal repair zone strength. The lower seroma rate and similar collagenization to controls induced by OCA suggests its improved behavior over the other two glues. This article deals with a preclinical study to examine different aspects of the repair process in the host of three alkyl cyanoacrylates (n-butyl (GLUBRAN 2), n-hexyl (IFABOND), and n-octyl cyanoacrylate (EVOBOND)) compared to sutures (control), in the fixation of surgical meshes for hernia repair. It goes into detail about collagen deposition in the repair zone at short and medium term. The

  6. Exotic herbivores on a shared native host: tissue quality after individual, simultaneous, and sequential attack.

    PubMed

    Gómez, Sara; Orians, Colin M; Preisser, Evan L

    2012-08-01

    Plants in nature are often attacked by multiple enemies whose effect on the plant cannot always be predicted based on the outcome of individual attacks. We investigated how two invasive herbivores, the hemlock woolly adelgid (Adelges tsugae) (HWA) and the elongate hemlock scale (Fiorinia externa) (EHS), alter host plant quality (measured as amino acid concentration and composition) when feeding individually or jointly on eastern hemlock (Tsuga canadensis), an important long-lived forest tree that is in severe decline. The joint herbivore treatments included both simultaneous and sequential infestations by the two herbivores. We expected resource depletion over time, particularly in response to feeding by HWA. In contrast, HWA dramatically increased the concentration and altered the composition of individual free amino acids. Compared to control trees, HWA increased total amino acid concentration by 330% after 1 year of infestation. Conversely, EHS had a negligible effect when feeding individually. Interestingly, there was a marginally significant HWA × EHS interaction that suggests the potential for EHS presence to reduce the impact of HWA on foliage quality when the two species co-occur. We suggest indirect effects of water stress as a possible physiological mechanism for our results. Understanding how species interactions change the physiology of a shared host is crucial to making more accurate predictions about host mortality and subsequent changes in affected communities and ecosystems, and to help design appropriate management plans.

  7. Cytochemical Labeling for Fungal and Host Components in Plant Tissues Inoculated with Fungal Wilt Pathogens

    NASA Astrophysics Data System (ADS)

    Ouellette, G. B.; Baayen, R. P.; Chamberland, H.; Simard, M.; Rioux, D.; Charest, P. M.

    2004-08-01

    Antibodies to detect pectin in present investigations attached to distinct fibrils in vessel lumina. In carnation infected with an isolate of Fusarium oxysporum f.sp., labeling of pathogen cells also occurred; in a resistant cultivar (cv.), it was coincident with proximate pectin fibrils and linked to altered fungal walls, which was the opposite in the susceptible cv., indicating that hindrance of pathogen ability to degrade pectin may be related to resistance. Labeling of the fungus in culture was nil, except in media containing pectin, showing that pectin is not native to the pathogen. Labeling of fungal walls for cellulose in elm (inoculated with Ophiostoma novo-ulmi) and carnation also occurred, linked to adsorbed host wall components. The chitin probe often attached to dispersed matter, in vessel lumina, traceable to irregularly labeled fungal cells and host wall degradation products. With an anti-horseradish peroxidase probe, host and fungal walls were equally labeled, and with a glucosidase, differences of labeling between these walls were observed, depending on pH of the test solution. Fungal extracellular matter and filamentous structures, present in fungal walls, predominantly in another elm isolate (Phaeotheca dimorphospora), did not label with any of the probes used. However, in cultures of this fungus, extracellular material labeled, even at a distance from the colony margin, with an anti-fimbriae probe.

  8. COX2 (PTGS2) gene methylation in epithelial, subepithelial lymphocyte and stromal tissue compartments in a spectrum of esophageal squamous neoplasia

    PubMed Central

    Dawsey, Sonja P.; Roth, Mark J.; Adams, Lisa; Hu, Nan; Wang, Quan-Hong; Taylor, Philip R.; Woodson, Karen

    2008-01-01

    Background Previous studies have shown important effects of stromal elements in carcinogenesis. To explore the tumor-stromal relationship in esophageal neoplasia, we examined methylation of COX-2 (PTGS2), a gene etiologically associated with the development of gastrointestinal cancers, in adjacent foci of epithelium, subepithelial lymphocytes and non-lymphocytic stromal cells found in sections of normal squamous epithelium, squamous dysplasia and invasive esophageal squamous cell carcinoma. Methods Adjacent foci of epithelium, subepithelial lymphocytic aggregates and non-lymphocytic stromal tissues were laser microdissected from six fully embedded, ethanol fixed, esophagectomy samples from Shanxi, China, a high-risk region for esophageal cancer. Promoter CpG site-specific hypermethylation status of COX-2 was determined using real-time methylation specific PCR (qMS-PCR) based on Taqman Chemistry. The methylation status of a subset of samples was confirmed by pyrosequencing. Results Forty-nine microdissected foci were analyzed. COX-2 gene methylation was significantly more common in subepithelial lymphocytes (12/16 (75% of all foci)) than in epithelial foci (3/16 (19%)) or foci of non-lymphocytic stromal tissues (3/17 (18%)) (Fisher’s Exact p=0.05). Two of three epithelial samples and all three stromal samples that showed COX-2 methylation were adjacent to foci of methylated subepithelial lymphocytes. Pyrosequencing confirmed the methylation status in a subset of samples. Conclusions In these esopohageal cancer patients, COX-2 gene methylation was more common in subepithelial lymphocytes than in adjacent epithelial or stromal cells in both grades of dysplasia and in foci of invasive cancer. These findings raise the possibility that methylation of subepithelial lymphocytes may be important for tumorigenesis. Future studies of gene methylation should consider separate evaluation of epithelial and non-epithelial cell populations. Condensed abstract COX2 (PTGS2) gene

  9. Immortalization of epithelial-like cells from human liver tissue with SV40 T-antigen gene.

    PubMed

    Miyazaki, M; Mihara, K; Bai, L; Kano, Y; Tsuboi, S; Endo, A; Seshimo, K; Yoshioka, T; Namba, M

    1993-05-01

    The cells derived from the human embryo liver tissue were transfected with a plasmid pSV3neo containing both the large and small T-antigen gene of the early region of simian virus 40 (SV40), and two cell strains, OUMS-21 and -22, were obtained. OUMS-22 cells, to date, have reached over 100 population doublings through a culture crisis and are considered to have become an immortal cell line. However, OUMS-21 cells failed to become an immortal cell line. Both OUMS-21 and -22 cells were SV40 T-antigen-positive, epithelial-like, and immunoreactive against an anti-keratin 18 monoclonal antibody but against neither an anti-vimentin nor an anti-von Willebrandt factor VIII monoclonal antibody. The staining pattern of cytokeratin in these cells was similar to that in the differentiated human hepatoblastoma and hepatocellular carcinoma cell lines but not to that in the human cholangiocellular carcinoma cell lines. OUMS-21 and -22 cells expressed neither alpha-fetoprotein nor albumin mRNAs. These cells showed no tyrosine aminotransferase activity. However, both OUMS-21 and -22 cells were sensitive to cytotoxicity of aflatoxin B1, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole, and benzo[a]pyrene, whereas human embryo lung fibroblasts were insensitive to the cytotoxicity of these carcinogens. These findings suggest that OUMS-21 and -22 cells may arise from undifferentiated liver stem cells or from hepatocytes that lost their ability to express the liver-specific functions prior to immortalization. Both OUMS-21 and -22 cells expressed glutathione S-transferase pi (GST-pi) mRNA. The expression of GST-pi mRNA highly increased in OUMS-22 cells with their immortalization. Karyotypic analysis showed that numerical and structural aberrations of the chromosomes were profound, but neither specific events nor marker chromosomes were found in OUMS-21 and -22 cells. Both OUMS-21 and -22 cells could grow in soft agar, but they were not tumorigenic when transplanted into nude mice.

  10. Expression of cyclin D1 in epithelial tissues of transgenic mice results in epidermal hyperproliferation and severe thymic hyperplasia.

    PubMed Central

    Robles, A I; Larcher, F; Whalin, R B; Murillas, R; Richie, E; Gimenez-Conti, I B; Jorcano, J L; Conti, C J

    1996-01-01

    To study the involvement of cyclin D1 in epithelial growth and differentiation and its putative role as an oncogene in skin, transgenic mice were developed carrying the human cyclin D1 gene driven by a bovine keratin 5 promoter. As expected, all squamous epithelia including skin, oral mucosa, trachea, vaginal epithelium, and the epithelial compartment of the thymus expressed aberrant levels of cyclin D1. The rate of epidermal proliferation increased dramatically in transgenic mice, which also showed basal cell hyperplasia. However, epidermal differentiation was unaffected, as shown by normal growth arrest of newborn primary keratinocytes in response to high extracellular calcium. Moreover, an unexpected phenotype was observed in the thymus. Transgenic mice developed a severe thymic hyperplasia that caused premature death due to cardio-respiratory failure within 4 months of age. By 14 weeks, the thymi of transgenic mice increased in weight up to 40-fold, representing 10% of total body weight. The hyperplastic thymi had normal histology revealing a well-differentiated cortex and medulla, which supported an apparently normal T-cell developmental program based on the distribution of thymocyte subsets. These results suggest that proliferation and differentiation of epithelial cells are under independent genetic controls in these organs and that cyclin D1 can modulate epithelial proliferation without altering the initiation of differentiation programs. No spontaneous development of epithelial tumors or thymic lymphomas was perceived in transgenic mice during their first 8 months of life, although they continue under observation. This model provides in vivo evidence of the action of cyclin D1 as a pure mediator of proliferation in epithelial cells. Images Fig. 1 Fig. 2 Fig. 3 PMID:8755527

  11. Povidone-iodine-induced cell death in cultured human epithelial HeLa cells and rat oral mucosal tissue.

    PubMed

    Sato, So; Miyake, Masao; Hazama, Akihiro; Omori, Koichi

    2014-07-01

    Although povidone-iodine (PVP-I) has been used as a gargle since 1956, its effectiveness and material safety have been remained controversial. The aim of this study was to investigate the toxicity of PVP-I to epithelial cells in a concentration range significantly lower than that used clinically. Study design was in vitro laboratory investigations and in vivo histological and immunologic analysis. We examined the effects of PVP-I at concentrations of 1 × 10(-2) to 1 × 10(3) μM and 1 × 10(-4) to 1 × 10 μM on HeLa cells as a model of epithelial cells and rat oral mucosa, respectively, after 1 or 2 days of exposure. Annexin V/FLUOS was used to distinguish live, apoptotic and necrotic cells. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method was also used to observe whether apoptotic epithelial cells exist in rat oral mucosa after 1 day of exposure of PVP-I. HeLa cells developed concentration-dependent cytotoxicity, and epithelium of rat oral mucosa was thinned in a concentration-dependent manner. HeLa cell apoptosis increased after 1 × 10(0) μM of PVP-I exposure for 2 days. In the TUNEL method, many apoptotic epithelial cells were observed in the rat oral mucosa after 1 day of exposure to diluted 1 × 10(-2) μM of PVP-I, but minimal apoptotic epithelial cells were observed using 1 × 10(-3) μM of PVP-I. Our findings suggest that exposure to PVP-I, of which concentrations are even lower than those used clinically, causes toxicity in epithelial cells. This knowledge would help us better understand the risk of the use of PVP-I against mucosa.

  12. Expression of tumor necrosis factor-alpha-induced protein 8 in pancreas tissues and its correlation with epithelial growth factor receptor levels.

    PubMed

    Liu, Ke; Qin, Cheng-Kun; Wang, Zhi-Yi; Liu, Su-Xia; Cui, Xian-Ping; Zhang, Dong-Yuan

    2012-01-01

    Tumor necrosis factor (TNF)-alpha-induced protein 8 (TNFAIP8 or TIPE) is a recently identified protein considered to be associated with carcinogenesis. To investigate its expression pattern in pancreatic cancer patients and to analyse its correlation with clinicopathological significance and the expression levels of epithelial growth factor receptor (EGFR), immunohistochemistry was performed to detect the TNFAIP8 and EGFR proteins in pancreatic cancers, pancreatitis tissues, and healthy controls. The results showed stronger staining of TNFAIP8 protein in pancreatic cancer tissues compared with normal pancreas tissue. Furthermore, in 56 patients with pancreatic cancer, the expression levels of TNFAIP8 in patients with low tumor stage was higher than that with high tumor stage, and correlated with tumor staging and lymph node metastasis (P<0.05). Furthermore, TNFAIP8 expression positively correlated with EGFR levels (r=0.671135, P<0.05). These results indicate that TNFAIP8 may play important roles in the progression of pancreatic cancer.

  13. Endogenous IL-33 is highly expressed in mouse epithelial barrier tissues, lymphoid organs, brain, embryos, and inflamed tissues: in situ analysis using a novel Il-33-LacZ gene trap reporter strain.

    PubMed

    Pichery, Mélanie; Mirey, Emilie; Mercier, Pascale; Lefrancais, Emma; Dujardin, Arnaud; Ortega, Nathalie; Girard, Jean-Philippe

    2012-04-01

    IL-33 (previously known as NF from high endothelial venules) is an IL-1 family cytokine that signals through the ST2 receptor and drives cytokine production in mast cells, basophils, eosinophils, invariant NKT and NK cells, Th2 lymphocytes, and type 2 innate immune cells (natural helper cells, nuocytes, and innate helper 2 cells). Little is known about endogenous IL-33; for instance, the cellular sources of IL-33 in mouse tissues have not yet been defined. In this study, we generated an Il-33-LacZ gene trap reporter strain (Il-33(Gt/Gt)) and used this novel tool to analyze expression of endogenous IL-33 in vivo. We found that the Il-33 promoter exhibits constitutive activity in mouse lymphoid organs, epithelial barrier tissues, brain, and embryos. Immunostaining with anti-IL-33 Abs, using Il-33(Gt/Gt) (Il-33-deficient) mice as control, revealed that endogenous IL-33 protein is highly expressed in mouse epithelial barrier tissues, including stratified squamous epithelia from vagina and skin, as well as cuboidal epithelium from lung, stomach, and salivary gland. Constitutive expression of IL-33 was not detected in blood vessels, revealing the existence of species-specific differences between humans and mice. Importantly, IL-33 protein was always localized in the nucleus of producing cells with no evidence for cytoplasmic localization. Finally, strong expression of the Il-33-LacZ reporter was also observed in inflamed tissues, in the liver during LPS-induced endotoxin shock, and in the lung alveoli during papain-induced allergic airway inflammation. Together, our findings support the possibility that IL-33 may function as a nuclear alarmin to alert the innate immune system after injury or infection in epithelial barrier tissues.

  14. Transplantation of tectal tissue in rats. I. Organization of transplants and pattern of distribution of host afferents within them

    SciTech Connect

    Lund, R.D.; Harvey, A.R.

    1981-01-01

    We have examined the maturation of tectal tissue transplanted from fetal rats to the midbrain of newborns and have characterized the distribution of host retinal and cortical afferents within the transplants. The transplants develop characteristic internal order and connections which distinguish them from either embryonic cortex or retina placed in the same region. Host retinal afferents project to clearly circumscribed regions, where they synapse mainly on small dendrites or dendritic spines, and only rarely on vesicle-containing profiles. The retinorecipient areas contain few stained axons in neurofibrillar preparations and are almost always located at the surface of the transplant. There is very little overlap in the input from the two eyes into a single transplant even though the projections from each eye may lie adjacent to one another. Cortical afferents spread more broadly in the transplants, but are largely absent from areas of optic termination and from other more deeply located regions with sparse fiber staining properties. The observations suggest that when placed close to its normal location, tectal tissue can develop a number of features characteristic of normal superior colliculus. Appreciation of the internal order of the transplants makes it possible to investigate the cortical and retinal afferent pathways using physiological techniques.

  15. Comparative genomic and phenomic analysis of Clostridium difficile and Clostridium sordellii, two related pathogens with differing host tissue preference.

    PubMed

    Scaria, Joy; Suzuki, Haruo; Ptak, Christopher P; Chen, Jenn-Wei; Zhu, Yongzhang; Guo, Xiao-Kui; Chang, Yung-Fu

    2015-06-10

    Clostridium difficile and C. sordellii are two anaerobic, spore forming, gram positive pathogens with a broad host range and the ability to cause lethal infections. Despite strong similarities between the two Clostridial strains, differences in their host tissue preference place C. difficile infections in the gastrointestinal tract and C. sordellii infections in soft tissues. In this study, to improve our understanding of C. sordellii and C. difficile virulence and pathogenesis, we have performed a comparative genomic and phenomic analysis of the two. The global phenomes of C. difficile and C. sordellii were compared using Biolog Phenotype microarrays. When compared to C. difficile, C. sordellii was found to better utilize more complex sources of carbon and nitrogen, including peptides. Phenotype microarray comparison also revealed that C. sordellii was better able to grow in acidic pH conditions. Using next generation sequencing technology, we determined the draft genome of C. sordellii strain 8483 and performed comparative genome analysis with C. difficile and other Clostridial genomes. Comparative genome analysis revealed the presence of several enzymes, including the urease gene cluster, specific to the C. sordellii genome that confer the ability of expanded peptide utilization and survival in acidic pH. The identified phenotypes of C. sordellii might be important in causing wound and vaginal infections respectively. Proteins involved in the metabolic differences between C. sordellii and C. difficile should be targets for further studies aimed at understanding C. difficile and C. sordellii infection site specificity and pathogenesis.

  16. Impact Assessment of Cigarette Smoke Exposure on Organotypic Bronchial Epithelial Tissue Cultures: A Comparison of Mono-Culture and Coculture Model Containing Fibroblasts.

    PubMed

    Iskandar, Anita R; Xiang, Yang; Frentzel, Stefan; Talikka, Marja; Leroy, Patrice; Kuehn, Diana; Guedj, Emmanuel; Martin, Florian; Mathis, Carole; Ivanov, Nikolai V; Peitsch, Manuel C; Hoeng, Julia

    2015-09-01

    Organotypic 3D cultures of epithelial cells are grown at the air-liquid interface (ALI) and resemble the in vivo counterparts. Although the complexity of in vivo cellular responses could be better manifested in coculture models in which additional cell types such as fibroblasts were incorporated, the presence of another cell type could mask the response of the other. This study reports the impact of whole cigarette smoke (CS) exposure on organotypic mono- and coculture models to evaluate the relevancy of organotypic models for toxicological assessment of aerosols. Two organotypic bronchial models were directly exposed to low and high concentrations of CS of the reference research cigarette 3R4F: monoculture of bronchial epithelial cells without fibroblasts (BR) and coculture with fibroblasts (BRF) models. Adenylate kinase (AK)-based cytotoxicity, cytochrome P450 (CYP) 1A1/1B1 activity, tissue histology, and concentrations of secreted mediators into the basolateral media, as well as transcriptomes were evaluated following the CS exposure. The results demonstrated similar impact of CS on the AK-based cytotoxicity, CYP1A1/1B1 activity, and tissue histology in both models. However, a greater number of secreted mediators was identified in the basolateral media of the monoculture than in the coculture models. Furthermore, annotation analysis and network-based systems biology analysis of the transcriptomic profiles indicated a more prominent cellular stress and tissue damage following CS in the monoculture epithelium model without fibroblasts. Finally, our results indicated that an in vivo smoking-induced xenobiotic metabolism response of bronchial epithelial cells was better reflected from the in vitro CS-exposed coculture model.

  17. Pregnancy at early age is associated with a reduction of progesterone-responsive cells and epithelial Wnt signaling in human breast tissue.

    PubMed

    Muenst, Simone; Mechera, Robert; Däster, Silvio; Piscuoglio, Salvatore; Ng, Charlotte K Y; Meier-Abt, Fabienne; Weber, Walter P; Soysal, Savas D

    2017-04-04

    Pregnancy at early age is the most significant modifiable factor which consistently decreases lifetime breast cancer risk. However, the underlying mechanisms haven't been conclusively identified. Studies in mice suggest a reduction in progesterone-receptor (PR) sensitive epithelial cells as well as a downregulation of the Wnt signaling pathway as being one of the main mechanisms for the protective effect of early pregnancy. The aim of our study was to validate these findings in humans. We collected benign breast tissue of 125 women who had been stratified according to age at first pregnancy and the occurrence of subsequent breast cancer, and performed immunohistochemistry for PR, Wnt4 and the Wnt-target Versican. The number of PR positive epithelial cells was significantly lower in the group of women with early pregnancy and no subsequent breast cancer compared to the group of nulliparous women with subsequent invasive breast cancer (p = 0.0135). In women with early pregnancy, expression of Versican and Wnt4 was significantly lower compared to nulliparous women (p = 0.0036 and p = 0.0241 respectively), and Versican expression was also significant lower compared to women with late pregnancy (p < 0.0001). Our results confirm prior observations in mice and suggest a role of downregulation of epithelial Wnt signaling in the protective effect of early pregnancy in humans. This results in a decreased proliferation of stem/progenitor cells; therefore, the Wnt signaling pathway may represent a potential target for breast cancer prevention in humans.

  18. Cementum- and periodontal ligament-like tissue formation by dental follicle cell sheets co-cultured with Hertwig's epithelial root sheath cells.

    PubMed

    Bai, Yudi; Bai, Yuxiang; Matsuzaka, Kenichi; Hashimoto, Sadamitsu; Fukuyama, Tatsuro; Wu, Lian; Miwa, Tsuneyuki; Liu, Xiaohui; Wang, Xiaojing; Inoue, Takashi

    2011-06-01

    Dental follicle cells (DFCs) are believed contain the precursor cells of the periodontium and can form cell sheets by secreting extracellular matrix (ECM) proteins. Cell sheet engineering has been recently developed and applied successfully in the field of tissue regeneration. However, research on the in vitro characteristics of DFC sheets is lacking and an assessment of whether DFC sheets can produce periodontal tissues in vivo has not been reported. To test the characteristics and applicability of DFC sheets in this field, we established a co-culture system of rat DFCs and Hertwig's epithelial root sheath (HERS) cells in vitro, and included the following controls: a co-culture of DFCs and alveolar mucosa epithelial cells, DFCs with no cells in the upper chamber, and DFCs cultured without an upper chamber. After 3 weeks of co-culturing the cells, the DFC sheets were transplanted into adult male rats' omenta. One week after co-culturing DFCs with HERS cells, mRNA levels of collagen type I (COL-1), alkaline phosphatase (ALP), runt related transcription factor 2 (Runx 2) and bone sialoprotein (BSP) were increased significantly. In addition, after 3 weeks of co-culturing the cells, the numbers of ALP-, osteocalcin (OCN)-, BSP- and osteoprotegerin (OPG)-positive DFCs increased. The DFCs also produced more calcified nodules and exhibited an increased number of subcellular organelles, which are important for protein synthesis and secretion. Moreover, gap junctions were found between the experimental DFCs within the sheet. Five weeks of in vivo growth of DFC sheets pre-exposed to HERS cells led to the formation of cementum-like tissues, which were positive for OCN, BSP and OPG, as well as the formation of periodontal ligament-like tissues, which were positive for COL-1. In contrast, control cells only produced fibrous tissues. These results indicate that the DFC sheets induced by HERS cells are able to produce periodontal tissues through epithelial

  19. Microsatellite markers for direct genotyping of the crayfish plague pathogen Aphanomyces astaci (Oomycetes) from infected host tissues.

    PubMed

    Grandjean, Frédéric; Vrålstad, Trude; Diéguez-Uribeondo, Javier; Jelić, Mišel; Mangombi, Joa; Delaunay, Carine; Filipová, Lenka; Rezinciuc, Svetlana; Kozubíková-Balcarová, Eva; Guyonnet, Daniel; Viljamaa-Dirks, Satu; Petrusek, Adam

    2014-06-04

    Aphanomyces astaci is an invasive pathogenic oomycete responsible for the crayfish plague, a disease that has devastated European freshwater crayfish. So far, five genotype groups of th