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Sample records for pigment epithelium cell

  1. Culturing of retinal pigment epithelium cells.

    Science.gov (United States)

    Valtink, Monika; Engelmann, Katrin

    2009-01-01

    The retinal pigment epithelium (RPE) is a monolayer of cells adjacent to the photoreceptors of the retina. It plays a crucial role in maintaining photoreceptor health and survival. Degeneration or dysfunction of the RPE can lead to photoreceptor degeneration and as a consequence to visual impairment. The most common diseased state of the RPE becomes manifest in age-related macular degeneration, an increasing cause of blindness in the elderly. RPE cells are therefore of great interest to researchers working in the field of tissue engineering and cell transplantation. In fact, studies in animal models have proven that the transplantation of RPE cells can delay the course of photoreceptor degenerative diseases. Although first attempts to transplant RPE cells into the subretinal space in human individuals suffering from age-related macular degeneration were less successful, RPE cell transplantation is still favored as a future therapeutic option, and much work is done to develop and design cell transplants. Cell banking is a prerequisite to have well-differentiated and characterized cells at hand when needed for research purposes, but also for therapeutic approaches. In this chapter the authors will describe methods to isolate, culture and preserve adult human RPE cells for the purpose of RPE cell banking. Copyright 2009 S. Karger AG, Basel.

  2. Retinal Pigment Epithelium Cell Alignment on Nanostructured Collagen Matrices

    OpenAIRE

    Ulbrich, Stefan; Friedrichs, Jens; Valtink, Monika; Murovski, Simo; Franz, Clemens M.; Müller, Daniel J.; Richard H. W. Funk; Engelmann, Katrin

    2014-01-01

    We investigated attachment and migration of human retinal pigment epithelial cells (primary, SV40-transfected and ARPE-19) on nanoscopically defined, two-dimensional matrices composed of parallel-aligned collagen type I fibrils. These matrices were used non-cross-linked (native) or after riboflavin/UV-A cross-linking to study cell attachment and migration by time-lapse video microscopy. Expression of collagen type I and IV, MMP-2 and of the collagen-binding integrin subunit α2 were examined b...

  3. Retinoic acid from retinal pigment epithelium induces T regulatory cells.

    Science.gov (United States)

    Kawazoe, Yuko; Sugita, Sunao; Keino, Hiroshi; Yamada, Yukiko; Imai, Ayano; Horie, Shintaro; Mochizuki, Manabu

    2012-01-01

    Primary cultured retinal pigment epithelial (RPE) cells can convert T cells into T regulatory cells (Tregs) through inhibitory factor(s) including transforming growth factor β (TGFβ) in vitro. Retinoic acid (RA) enhances induction of CD4(+) Tregs in the presence of TGFβ. We investigated whether RA produced by RPE cells can promote generation of Tregs. We found that in vitro, RA-treated T cells expressed high levels of Foxp3 in the presence of recombinant TGFβ. In GeneChip analysis, cultured RPE cells constitutively expressed RA-associated molecules such as RA-binding proteins, enzymes, and receptors. RPE from normal mice, but not vitamin A-deficient mice, contained significant levels of TGFβ. RPE-induced Tregs from vitamin A-deficient mice failed to suppress activation of target T cells. Only a few Foxp3(+) T cells were found in intraocular cells from vitamin A-deficient experimental autoimmune uveitis (EAU) mice, whereas expression was higher in cells from normal EAU mice. RA receptor antagonist-pretreated or RA-binding protein-siRNA-transfected RPE cells failed to convert CD4(+) T cells into Tregs. Our data support the hypothesis that RPE cells produce RA, thereby enabling bystander T cells to be converted into Tregs through TGFβ promotion, which can then participate in the establishment of immune tolerance in the eye.

  4. Retinal pigment epithelium cell alignment on nanostructured collagen matrices.

    Science.gov (United States)

    Ulbrich, Stefan; Friedrichs, Jens; Valtink, Monika; Murovski, Simo; Franz, Clemens M; Müller, Daniel J; Funk, Richard H W; Engelmann, Katrin

    2011-01-01

    We investigated attachment and migration of human retinal pigment epithelial cells (primary, SV40-transfected and ARPE-19) on nanoscopically defined, two-dimensional matrices composed of parallel-aligned collagen type I fibrils. These matrices were used non-cross-linked (native) or after riboflavin/UV-A cross-linking to study cell attachment and migration by time-lapse video microscopy. Expression of collagen type I and IV, MMP-2 and of the collagen-binding integrin subunit α(2) were examined by immunofluorescence and Western blotting. SV40-RPE cells quickly attached to the nanostructured collagen matrices and aligned along the collagen fibrils. However, they disrupted both native and cross-linked collagen matrices within 5 h. Primary RPE cells aligned more slowly without destroying either native or cross-linked substrates. Compared to primary RPE cells, ARPE-19 cells showed reduced alignment but partially disrupted the matrices within 20 h after seeding. Expression of the collagen type I-binding integrin subunit α(2) was highest in SV40-RPE cells, lower in primary RPE cells and almost undetectable in ARPE-19 cells. Thus, integrin α(2) expression levels directly correlated with the degree of cell alignment in all examined RPE cell types. Specific integrin subunit α(2)-mediated matrix binding was verified by preincubation with an α(2)-function-blocking antibody, which impaired cell adhesion and alignment to varying degrees in primary and SV40-RPE cells. Since native matrices supported extended and directed primary RPE cell growth, optimizing the matrix production procedure may in the future yield nanostructured collagen matrices serving as transferable cell sheet carriers.

  5. In vitro differentiation of retinal pigment epithelium from adult retinal stem cells.

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    Aruta, Claudia; Giordano, Francesca; De Marzo, Anna; Comitato, Antonella; Raposo, Graça; Nandrot, Emeline F; Marigo, Valeria

    2011-02-01

    One of the limitations in molecular and functional studies of the retinal pigment epithelium (RPE) has been the lack of an in vitro system retaining all the features of in vivo RPE cells. Retinal pigment epithelium cell lines do not show characteristics typical of a functional RPE, such as pigmentation and expression of specific markers. The present study was aimed at the development of culture conditions to differentiate, in vitro, retinal stem cells (RSC), derived from the adult ciliary body, into a functional RPE. Retinal stem cells were purified from murine eyes, grown as pigmented neurospheres and induced to differentiate into RPE on an extracellular matrix substrate using specific culture conditions. After 7-15 days of culture, pigmented cells with an epithelial morphology showed a polarized organization and a capacity for phagocytosis. We detected different stages of melanogenesis in cells at 7 days of differentiation, whereas RPE at 15 days contained only mature melanosomes. These data suggest that our protocol to differentiate RPE in vitro can provide a useful model for molecular and functional studies.

  6. Derivation of Neural Progenitors and Retinal Pigment Epithelium from Common Marmoset and Human Pluripotent Stem Cells

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    Laughing Bear Torrez

    2012-01-01

    Full Text Available Embryonic and induced pluripotent stem cells (IPSCs derived from mammalian species are valuable tools for modeling human disease, including retinal degenerative eye diseases that result in visual loss. Restoration of vision has focused on transplantation of neural progenitor cells (NPCs and retinal pigmented epithelium (RPE to the retina. Here we used transgenic common marmoset (Callithrix jacchus and human pluripotent stem cells carrying the enhanced green fluorescent protein (eGFP reporter as a model system for retinal differentiation. Using suspension and subsequent adherent differentiation cultures, we observed spontaneous in vitro differentiation that included NPCs and cells with pigment granules characteristic of differentiated RPE. Retinal cells derived from human and common marmoset pluripotent stem cells provide potentially unlimited cell sources for testing safety and immune compatibility following autologous or allogeneic transplantation using nonhuman primates in early translational applications.

  7. A strategy to ensure safety of stem cell-derived retinal pigment epithelium cells.

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    Choudhary, Parul; Whiting, Paul John

    2016-09-02

    Cell replacement and regenerative therapy using embryonic stem cell-derived material holds promise for the treatment of several pathologies. However, the safety of this approach is of prime importance given the teratogenic potential of residual stem cells, if present in the differentiated cell product. Using the example of embryonic stem cell-derived retinal pigment epithelium (RPE) for the treatment of age-related macular degeneration, we present a novel strategy for ensuring the absence of stem cells in the RPE population. Based on an unbiased screening approach, we identify and validate the expression of CD59, a cell surface marker expressed on RPE but absent on stem cells. We further demonstrate that flow sorting on the basis of CD59 expression can effectively purify RPE and deplete stem cells, resulting in a population free from stem cell impurity. This purification helps to ensure removal of stem cells and hence increases the safety of cells that may be used for clinical transplantation. This strategy can potentially be applied to other pluripotent stem cell-derived material and help mitigate concerns of using such cells for therapy.

  8. MicroRNA expression profiles of human iPS cells, retinal pigment epithelium derived from iPS, and fetal retinal pigment epithelium.

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    Greene, Whitney A; Muñiz, Alberto; Plamper, Mark L; Kaini, Ramesh R; Wang, Heuy-Ching

    2014-06-24

    The objective of this report is to describe the protocols for comparing the microRNA (miRNA) profiles of human induced-pluripotent stem (iPS) cells, retinal pigment epithelium (RPE) derived from human iPS cells (iPS-RPE), and fetal RPE. The protocols include collection of RNA for analysis by microarray, and the analysis of microarray data to identify miRNAs that are differentially expressed among three cell types. The methods for culture of iPS cells and fetal RPE are explained. The protocol used for differentiation of RPE from human iPS is also described. The RNA extraction technique we describe was selected to allow maximal recovery of very small RNA for use in a miRNA microarray. Finally, cellular pathway and network analysis of microarray data is explained. These techniques will facilitate the comparison of the miRNA profiles of three different cell types.

  9. Role of Pigment Epithelium-Derived Factor in Stem/Progenitor Cell-Associated Neovascularization

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    Jung-Tung Liu

    2012-01-01

    Full Text Available Pigment epithelium-derived factor (PEDF was first identified in retinal pigment epithelium cells. It is an endogenously produced protein that is widely expressed throughout the human body such as in the eyes, liver, heart, and adipose tissue; it exhibits multiple and varied biological activities. PEDF is a multifunctional protein with antiangiogenic, antitumorigenic, antioxidant, anti-inflammatory, antithrombotic, neurotrophic, and neuroprotective properties. More recently, PEDF has been shown to be the most potent inhibitor of stem/progenitor cell-associated neovascularization. Neovascularization is a complex process regulated by a large, interacting network of molecules from stem/progenitor cells. PEDF is also involved in the pathogenesis of angiogenic eye disease, tumor growth, and cardiovascular disease. Novel antiangiogenic agents with tolerable side effects are desired for the treatment of patients with various diseases. Here, we review the value of PEDF as an important endogenous antiangiogenic molecule; we focus on the recently identified role of PEDF as a possible new target molecule to influence stem/progenitor cell-related neovascularization.

  10. Prolactin protects retinal pigment epithelium by inhibiting sirtuin 2-dependent cell death.

    Science.gov (United States)

    Meléndez García, Rodrigo; Arredondo Zamarripa, David; Arnold, Edith; Ruiz-Herrera, Xarubet; Noguez Imm, Ramsés; Baeza Cruz, German; Adán, Norma; Binart, Nadine; Riesgo-Escovar, Juan; Goffin, Vincent; Ordaz, Benito; Peña-Ortega, Fernando; Martínez-Torres, Ataúlfo; Clapp, Carmen; Thebault, Stéphanie

    2016-05-01

    The identification of pathways necessary for retinal pigment epithelium (RPE) function is fundamental to uncover therapies for blindness. Prolactin (PRL) receptors are expressed in the retina, but nothing is known about the role of PRL in RPE. Using the adult RPE 19 (ARPE-19) human cell line and mouse RPE, we identified the presence of PRL receptors and demonstrated that PRL is necessary for RPE cell survival via anti-apoptotic and antioxidant actions. PRL promotes the antioxidant capacity of ARPE-19 cells by reducing glutathione. It also blocks the hydrogen peroxide-induced increase in deacetylase sirtuin 2 (SIRT2) expression, which inhibits the TRPM2-mediated intracellular Ca(2+) rise associated with reduced survival under oxidant conditions. RPE from PRL receptor-null (prlr(-/-)) mice showed increased levels of oxidative stress, Sirt2 expression and apoptosis, effects that were exacerbated in animals with advancing age. These observations identify PRL as a regulator of RPE homeostasis.

  11. Prolactin protects retinal pigment epithelium by inhibiting sirtuin 2-dependent cell death

    Directory of Open Access Journals (Sweden)

    Rodrigo Meléndez García

    2016-05-01

    Full Text Available The identification of pathways necessary for retinal pigment epithelium (RPE function is fundamental to uncover therapies for blindness. Prolactin (PRL receptors are expressed in the retina, but nothing is known about the role of PRL in RPE. Using the adult RPE 19 (ARPE-19 human cell line and mouse RPE, we identified the presence of PRL receptors and demonstrated that PRL is necessary for RPE cell survival via anti-apoptotic and antioxidant actions. PRL promotes the antioxidant capacity of ARPE-19 cells by reducing glutathione. It also blocks the hydrogen peroxide-induced increase in deacetylase sirtuin 2 (SIRT2 expression, which inhibits the TRPM2-mediated intracellular Ca2+ rise associated with reduced survival under oxidant conditions. RPE from PRL receptor-null (prlr−/− mice showed increased levels of oxidative stress, Sirt2 expression and apoptosis, effects that were exacerbated in animals with advancing age. These observations identify PRL as a regulator of RPE homeostasis.

  12. The Retinal Pigment Epithelium: a Convenient Source of New Photoreceptor cells?

    Directory of Open Access Journals (Sweden)

    Shu-Zhen Wang

    2014-01-01

    Full Text Available Recent success in restoring visual function through photoreceptor replacement in mouse models of photoreceptor degeneration intensifies the need to generate or regenerate photoreceptor cells for the ultimate goal of using cell replacement therapy for blindness caused by photoreceptor degeneration. Current research on deriving new photoreceptors for replacement, as regenerative medicine in general, focuses on the use of embryonic stem cells and induced pluripotent stem (iPS cells to generate transplantable cells. Nonetheless, naturally occurring regeneration, such as wound healing, involves awakening cells at or near a wound site to produce new cells needed to heal the wound. Here we discuss the possibility of tweaking an ocular tissue, the retinal pigment epithelium (RPE, to produce photoreceptor cells in situ in the eye. Unlike the neural retina, the RPE in adult mammals maintains cell proliferation capability. Furthermore, progeny cells from RPE proliferation may differentiate into cells other than RPE. The combination of proliferation and plasticity opens a question of whether they could be channeled by a regulatory gene with pro-photoreceptor activity towards photoreceptor production. Studies using embryonic chick and transgenic mouse showed that indeed photoreceptor-like cells were produced in culture and in vivo in the eye using genedirected reprogramming of RPE cells, supporting the feasibility of using the RPE as a convenient source of new photoreceptor cells for in situ retinal repair without involving cell transplantation.

  13. Unraveling the cellular uptake of bioreducible poly(amido amine) — Gene complexes in cells of the retinal pigment epithelium

    NARCIS (Netherlands)

    Vercauteren, D.; Piest, M.; Soraj, M. Al; Jones, A.T.; Engbersen, J.F.J.; Smedt, de S.C.; Braeckmans, K.

    2010-01-01

    In vitro endocytosis of gene complexes composed of a bioreducible polyamidoamine CBA ABOL and plasmid DNA, in cells of the retinal pigment epithelium (RPE) was studied, the latter being an interesting target for ocular gene therapy. We found that cationic CBA ABOL DNA polyplexes attach to cell surfa

  14. Change of morphological and functional characteristics of retinal pigment epithelium cells during cultivation of retinal pigment epithelium-choroid perfusion tissue culture.

    Science.gov (United States)

    Miura, Yoko; Klettner, Alexa; Noelle, Bernhard; Hasselbach, Heike; Roider, Johann

    2010-01-01

    To evaluate the changes of morphological and functional characteristics of the retinal pigment epithelium (RPE)-choroid perfusion culture during cultivation. PorcineRPE-choroid tissue was cultivated in a perfusion tissue culture system. After the indicated times, histology, immunolocalization of collagen IV and von Willebrand factor, RPE cell viability with calcein-AM, TUNEL assay and occludin immunolocalization of RPE cells were examined. The tissue was treated with selective RPE treatment laser after different time periods and the wound healing response was characterized. Vascular endothelial growth factor secretion was measured by enzyme-linked immunosorbent assay. On day 8, prominent morphological degenerative changes of RPE cells were observed in histology. According to the immunohistochemistry for collagen IV, the Bruch's membrane did not display any obvious decomposition until day 8. Von Willebrand factor staining decreased during cultivation, especially at the choriocapillaris. Calcein-AM staining and TUNEL assay displayed the increase of apoptotic changes in only a minority of the cells on day 4, but in many cells on day 8. Occludin delocalization was observed on day 8. Selective RPE treatment laser-produced wounds were completely closed by monolayer RPE when wounded on fresh and 3-day-old cultures, but not when wounded on 6-day-old cultures. Vascular endothelial growth factor secretion was stable between days 2 and 5, but increased after that. Under the stated culture perfusion conditions, porcine RPE-choroid tissue was suitable for experimentation up to 5 days of maintenance. Copyright 2009 S. Karger AG, Basel.

  15. Proteomic Profiling of Cigarette Smoke Induced Changes in Retinal Pigment Epithelium Cells.

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    Merl-Pham, Juliane; Gruhn, Fabian; Hauck, Stefanie M

    2016-01-01

    Age-related macular degeneration (AMD) is a medical condition usually affecting older adults and resulting in a loss of vision in the macula, the center of the visual field. The dry form of this disease presents with atrophy of the retinal pigment epithelium, resulting in the detachment of the retina and loss of photoreceptors. Cigarette smoke is one main risk factor for dry AMD and increases the risk of developing the disease by three times. In order to understand the influence of cigarette smoke on retinal pigment epithelial cells, cultured human ARPE-19 cells were treated with cigarette smoke extract for 24 h. Using quantitative mass spectrometry more than 3000 proteins were identified and their respective abundances were compared between cigarette smoke-treated and untreated cells. Altogether 1932 proteins were quantified with at least two unique peptides, with 686 proteins found to be significantly differentially abundant with p > 0.05. Of these proteins the abundance of 64 proteins was at least 2-fold down-regulated after cigarette smoke treatment while 120 proteins were 2-fold up-regulated. The analysis of associated biological processes revealed an alteration of proteins involved in RNA processing and transport as well as extracellular matrix remodelling in response to cigarette smoke treatment.

  16. Aliskiren inhibits the renin-angiotensin system in retinal pigment epithelium cells.

    Science.gov (United States)

    Simão, Sónia; Santos, Daniela F; Silva, Gabriela A

    2016-09-20

    Observations of increased angiotensin II levels and activation of the (pro)renin receptor in retinopathies support the role of ocular renin-angiotensin system (RAS) in the development of retinal diseases. While targeting RAS presents significant therapeutic potential, current RAS-based therapies are ineffective halting the progression of these diseases. A new class of drugs, the direct renin inhibitors such as aliskiren, is a potential therapeutic alternative. However, it is unclear how aliskiren acts in the retina, in particular in the retinal pigment epithelium (RPE), the structure responsible for the maintenance of retinal homeostasis whose role is deeply compromised in retinal diseases. We firstly analyzed the expression and activity of the main RAS components in RPE cells. Time- and concentration-dependent treatments with aliskiren were performed to modulate different pathways of the RAS in RPE cells. Our data demonstrate that RPE cells express the main RAS constituents. Exposure of RPE cells to aliskiren inhibited the activity of renin and consequently decreased the levels of angiotensin II. Additionally, aliskiren reduced the translocation of the (pro)renin receptor to the cellular membrane of RPE cells preventing the activation of ERK1/2. Our findings of the RPE well-defined RAS, together with the demonstration that aliskiren effectively blocks this system at different steps of the cascade, suggest that aliskiren might be an alternative and successful drug in preventing the deleterious effects derived from the overactivation of the RAS, known to contribute to the pathogenesis of different retinal diseases.

  17. Cytotoxicity and genotoxicity of bacterial magnetosomes against human retinal pigment epithelium cells

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    Qi, Lei; Lv, Xiujuan; Zhang, Tongwei; Jia, Peina; Yan, Ruiying; Li, Shuli; Zou, Ruitao; Xue, Yuhua; Dai, Liming

    2016-06-01

    A variety of nanomaterials have been developed for ocular diseases. The ability of these nanomaterials to pass through the blood-ocular barrier and their biocompatibility are essential characteristics that must be considered. Bacterial magnetosomes (BMs) are a type of biogenic magnetic nanomaterials synthesized by magnetotactic bacteria. Due to their unique biomolecular membrane shell and narrow size distribution of approximately 30 nm, BMs can pass through the blood-brain barrier. The similarity of the blood-ocular barrier to the blood-brain barrier suggests that BMs have great potential as treatments for ocular diseases. In this work, BMs were isolated from magnetotactic bacteria and evaluated in various cytotoxicity and genotoxicity studies in human retinal pigment epithelium (ARPE-19) cells. The BMs entered ARPE-19 cells by endocytosis after a 6-h incubation and displayed much lower cytotoxicity than chemically synthesized magnetic nanoparticles (MNPs). MNPs exhibited significantly higher genotoxicity than BMs and promoted the expression of Bax (the programmed cell death acceleration protein) and the induction of greater cell necrosis. In BM-treated cells, apoptosis tended to be suppressed via increased expression of the Bcl-2 protein. In conclusion, BMs display excellent biocompatibility and potential for use in the treatment of ocular diseases.

  18. Pigment Epithelium-derived Factor in Cataractous Aqueous Humor and Lens Epithelial Cells

    Institute of Scientific and Technical Information of China (English)

    Tian Liu; Yizhi Liu; Mingxing Wu

    2006-01-01

    Purpose:To study the characteristics of PEDF in cataractous aqueous humor and its expression in human lens epithelium.Methods:The PEDF concentration in the aqueous humor was measured by enzyme linked immunosorbent assay in senile (130cases) and congenital (18cases) cataract patients who underwent cataract phacoemulsification extraction surgery. Anterior lens capsular specimens were obtained from these patients to count lens epithelial cells(LEC) density. The Lens Opacities Classification System Ⅲ was used to classify the senile cataracts as cortical, nuclear, posterior subcapsular and mixed types of opacity, and quantitative analysis of the nuclear opacities was performed by Pentacam Scheimpflug imaging system. Anterior lens capsular specimens from another senile(10cases) and congenital (10cases) cataract were collected for immunofluorescence with polyclonal antibodies specific to human pigment epithelium-derived factor(PEDF).Results:The mean aqueous level of PEDF was(178. 9±87. 5)ng/ml, and there was negative linear correlation of PEDF level and age (r=0. 811, P < 0. 001) . In senile cases, the aqueous PEDF concentration decreased with increasing nuclear opacities(r=0. 447, P < 0.01 ), and the mean PEDF level in nuclear cataract was significantly lower than that in posterior subcapsular opacity (P < 0.01 ) . PEDF immunostaining was detected in LEC of all capsular specimens.Conclusion :The PEDF level in human aqueous humor is related to age, types of cataracts and lens opacity. PEDF also express in human LEC. The study results suggest PEDF may regulate and/or protect LEC by paracrine and autocrine, and lack of PEDF may play a role in cataractogenesis.

  19. Imaging human retinal pigment epithelium cells using adaptive optics optical coherence tomography

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    Liu, Zhuolin; Kocaoglu, Omer P.; Turner, Timothy L.; Miller, Donald T.

    2016-03-01

    Retinal pigment epithelium (RPE) cells are vital to health of the outer retina, but are often compromised in ageing and major ocular diseases that lead to blindness. Early manifestation of RPE disruption occurs at the cellular level, and while biomarkers at this scale hold considerable promise, RPE cells have proven extremely challenging to image in the living human eye. We present a novel method based on optical coherence tomography (OCT) equipped with adaptive optics (AO) that overcomes the associated technical obstacles. The method takes advantage of the 3D resolution of AO-OCT, but more critically sub-cellular segmentation and registration that permit organelle motility to be used as a novel contrast mechanism. With this method, we successfully visualized RPE cells and characterized their 3D reflectance profile in every subject and retinal location (3° and 7° temporal to the fovea) imaged to date. We have quantified RPE packing geometry in terms of cell density, cone-to-RPE ratio, and number of nearest neighbors using Voronoi and power spectra analyses. RPE cell density (cells/mm2) showed no significant difference between 3° (4,892+/-691) and 7° (4,780+/-354). In contrast, cone-to- RPE ratio was significantly higher at 3° (3.88+/-0.52:1) than 7° (2.31+/- 0.23:1). Voronoi analysis also showed most RPE cells have six nearest neighbors, which was significantly larger than the next two most prevalent associations: five and seven. Averaged across the five subjects, prevalence of cells with six neighbors was 51.4+/-3.58% at 3°, and 54.58+/-3.01% at 7°. These results are consistent with histology and in vivo studies using other imaging modalities.

  20. Escin activates AKT-Nrf2 signaling to protect retinal pigment epithelium cells from oxidative stress

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    Wang, Kaijun [Eye Center, The 2nd Affiliated Hospital, Medical College of Zhejiang University, Hangzhou (China); Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou (China); Jiang, Yiqian [The First People Hospital of Xiaoshan, Hangzhou (China); Wang, Wei; Ma, Jian [Eye Center, The 2nd Affiliated Hospital, Medical College of Zhejiang University, Hangzhou (China); Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou (China); Chen, Min, E-mail: eyedrchenminzj@163.com [Eye Center, The 2nd Affiliated Hospital, Medical College of Zhejiang University, Hangzhou (China); Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou (China)

    2015-12-25

    Here we explored the anti-oxidative and cytoprotective potentials of escin, a natural triterpene-saponin, against hydrogen peroxide (H{sub 2}O{sub 2}) in retinal pigment epithelium (RPE) cells. We showed that escin remarkably attenuated H{sub 2}O{sub 2}-induced death and apoptosis of established (ARPE-19) and primary murine RPE cells. Meanwhile, ROS production and lipid peroxidation by H{sub 2}O{sub 2} were remarkably inhibited by escin. Escin treatment in RPE cells resulted in NF-E2-related factor 2 (Nrf2) signaling activation, evidenced by transcription of anti-oxidant-responsive element (ARE)-regulated genes, including HO-1, NQO-1 and SRXN-1. Knockdown of Nrf2 through targeted shRNAs/siRNAs alleviated escin-mediated ARE gene transcription, and almost abolished escin-mediated anti-oxidant activity and RPE cytoprotection against H{sub 2}O{sub 2}. Reversely, escin was more potent against H{sub 2}O{sub 2} damages in Nrf2-over-expressed ARPE-19 cells. Further studies showed that escin-induced Nrf2 activation in RPE cells required AKT signaling. AKT inhibitors (LY294002 and perifosine) blocked escin-induced AKT activation, and dramatically inhibited Nrf2 phosphorylation, its cytosol accumulation and nuclear translocation in RPE cells. Escin-induced RPE cytoprotection against H{sub 2}O{sub 2} was also alleviated by the AKT inhibitors. Together, these results demonstrate that escin protects RPE cells from oxidative stress possibly through activating AKT-Nrf2 signaling.

  1. Optical properties of photoreceptor and retinal pigment epithelium cells investigated with adaptive optics optical coherence tomography

    Science.gov (United States)

    Liu, Zhuolin

    Human vision starts when photoreceptors collect and respond to light. Photoreceptors do not function in isolation though, but share close interdependence with neighboring photoreceptors and underlying retinal pigment epithelium (RPE) cells. These cellular interactions are essential for normal function of the photoreceptor-RPE complex, but methods to assess these in the living human eye are limited. One approach that has gained increased promise is high-resolution retinal imaging that has undergone tremendous technological advances over the last two decades to probe the living retina at the cellular level. Pivotal in these advances has been adaptive optics (AO) and optical coherence tomography (OCT) that together allow unprecedented spatial resolution of retinal structures in all three dimensions. Using these high-resolution systems, cone photoreceptor are now routinely imaged in healthy and diseased retina enabling fundamental structural properties of cones to be studied such as cell spacing, packing arrangement, and alignment. Other important cell properties, however, have remained elusive to investigation as even better imaging performance is required and thus has resulted in an incomplete understanding of how cells in the photoreceptor-RPE complex interact with light. To address this technical bottleneck, we expanded the imaging capability of AO-OCT to detect and quantify more accurately and completely the optical properties of cone photoreceptor and RPE cells at the cellular level in the living human retina. The first objective of this thesis was development of a new AO-OCT method that is more precise and sensitive, thus enabling a more detailed view of the 3D optical signature of the photoreceptor-RPE complex than was previously possible (Chapter 2). Using this new system, the second objective was quantifying the waveguide properties of individual cone photoreceptor inner and outer segments across the macula (Chapter 3). The third objective extended the AO

  2. Bystander effects elicited by single-cell photo-oxidative blue-light stimulation in retinal pigment epithelium cell networks

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    Ishii, Masaaki; Rohrer, Bärbel

    2017-01-01

    ‘Bystander effect’ refers to the induction of biological effects in cells not directly targeted. The retinal pigment epithelium consists of hexagonal cells, forming a monolayer interconnected by gap junctions (GJs). Oxidative stress initiated in an individual cell by photostimulation (488 nm) triggered changes in reactive oxygen species (ROS), Ca2+ and mitochondrial membrane potential (ψm). The Ca2+ signal was transmitted to neighboring cells slowly and non-uniformly; the ROS signal spread fast and radially. Increased Ca2+ levels were associated with a loss in ψm. GJ blockers prevented the spreading of the Ca2+, but not the ROS-related signal. The GJ-mediated Ca2+ wave was associated with cell death by 24 h, requiring endoplasmic reticulum–mitochondria Ca2+ transfer. Ensuing cell death was correlated with baseline Ca2+ levels, and baseline Ca2+ levels were correlated with pigmentation. Hence, local oxidative stress in a donor cell can trigger changes in certain connected recipient cells, a signal that required GJ communication and an ROS-Ca2+ dual-hit. Finally, damage apparently occurred in susceptible cells, which correlated with baseline Ca2+ levels. PMID:28179989

  3. Taurine inhibits interleukin-6 expression and release induced by ultraviolet B exposure to human retinal pigment epithelium cells.

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    Dayang, Wu; Jinsong, Zhang

    2015-01-01

    The massive uptake of compatible osmolytes is a self-protective response shared by retina exposed to hypertonic stress and ultraviolet stress. This study aimed to investigate the protective effects of taurine against ultraviolet damage in human retinal pigment epithelium cells. Real-time PCR, radioimmunoassay, ELISA and immunoassay were used to measure osmolyte uptake and IL-6 expression. Compared with normotonic stress, hypertonic stress led to an induction of osmolyte uptake including betaine, myoinositol and taurine. UVB exposure upregulated osmolyte transporter mRNA expression and increased osmolyte uptake respectively. Especially, taurine suppressed UVB-induced IL-6 mRNA expression significantly. The accumulation of IL-6 in UVB-exposed human retinal pigment epithelial cells supernatant was much slower when the cells were preincubated with taurine. Moreover, taurine suppressed IL-6 concentration in aqueous humour. The effect of compatible osmolyte taurine on IL-6 expression and release may play an important role in cell resistance and adaption to UVB exposure.

  4. Honeycomb porous films as permeable scaffold materials for human embryonic stem cell-derived retinal pigment epithelium.

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    Calejo, Maria Teresa; Ilmarinen, Tanja; Jongprasitkul, Hatai; Skottman, Heli; Kellomäki, Minna

    2016-07-01

    Age-related macular degeneration (AMD) is a leading cause of blindness in developed countries, characterised by the degeneration of the retinal pigment epithelium (RPE), a pigmented cell monolayer that closely interacts with the photoreceptors. RPE transplantation is thus considered a very promising therapeutic option to treat this disease. In this work, porous honeycomb-like films are for the first time investigated as scaffold materials for human embryonic stem cell-derived retinal pigment epithelium (hESC-RPE). By changing the conditions during film preparation, it was possible to produce films with homogeneous pore distribution and adequate pore size (∼3-5 µm), that is large enough to ensure high permeability but small enough to enable cell adherence and spreading. A brief dip-coating procedure with collagen type IV enabled the homogeneous adsorption of the protein to the walls and bottom of pores, increasing the hydrophilicity of the surface. hESC-RPE adhered and proliferated on all the collagen-coated materials, regardless of small differences in pore size. The differentiation of hESC-RPE was confirmed by the detection of specific RPE protein markers. These results suggest that the porous honeycomb films can be promising candidates for hESC-RPE tissue engineering, importantly enabling the free flow of ions and molecules across the material. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1646-1656, 2016.

  5. Early LPS-induced ERK activation in retinal pigment epithelium cells is dependent on PIP 2 -PLC.

    Science.gov (United States)

    Mateos, Melina V; Kamerbeek, Constanza B; Giusto, Norma M; Salvador, Gabriela A

    2016-06-01

    This article presents additional data regarding the study "The phospholipase D pathway mediates the inflammatory response of the retinal pigment epithelium" [1]. The new data presented here show that short exposure of RPE cells to lipopolysaccharide (LPS) induces an early and transient activation of the extracellular signal-regulated kinase (ERK1/2). This early ERK1/2 activation is dependent on phosphatidylinositol bisphosphate-phospholipase C (PIP2-PLC). On the contrary, neither the phospholipase D 1 (PLD1) nor the PLD2 inhibition is able to modulate the early ERK1/2 activation induced by LPS in RPE cells.

  6. Phospholipase D1 modulates protein kinase C-epsilon in retinal pigment epithelium cells during inflammatory response.

    Science.gov (United States)

    Tenconi, Paula E; Giusto, Norma M; Salvador, Gabriela A; Mateos, Melina V

    2016-12-01

    Inflammation is a key factor in the pathogenesis of several retinal diseases. In view of the essential role of the retinal pigment epithelium in visual function, elucidating the molecular mechanisms elicited by inflammation in this tissue could provide new insights for the treatment of retinal diseases. The aim of the present work was to study protein kinase C signaling and its modulation by phospholipases D in ARPE-19 cells exposed to lipopolysaccharide. This bacterial endotoxin induced protein kinase C-α/βII phosphorylation and protein kinase-ε translocation to the plasma membrane in ARPE-19 cells. Pre-incubation with selective phospholipase D inhibitors demonstrated that protein kinase C-α phosphorylation depends on phospholipase D1 and 2 while protein kinase C-ε activation depends only on phospholipase D1. The inhibition of α and β protein kinase C isoforms with Go 6976 did not modify the reduced mitochondrial function induced by lipopolysaccharide. On the contrary, the inhibition of protein kinase C-α, β and ε with Ro 31-8220 potentiated the decrease in mitochondrial function. Moreover, inhibition of protein kinase C-ε reduced Bcl-2 expression and Akt activation and increased Caspase-3 cleavage in cells treated or not with lipopolysaccharide. Our results demonstrate that through protein kinase C-ε regulation, phospholipase D1 protects retinal pigment epithelium cells from lipopolysaccharide-induced damage.

  7. Adeno-associated Virus Mediated LacZ Gene Transfect to Cultured Human Iris Pigment Epithelium Cells

    Institute of Scientific and Technical Information of China (English)

    Chun Zhang; Shibo Tang; Yan Luo; Xiaoling Liang; Jing Ma; Shaofen Lin

    2003-01-01

    Purpose: To study the feasibility of adeno-associated virus mediated gene transfection tocultured human iris pigment epithelium (IPE) cells in vitro.Methods: Recombinant replication deficient adeno-associated viruses (AAV) expressingLacZ gene were produced without helper virus. The LacZ gene was transduced into culturedhuman IPE cells.Results: Cultured human IPE cells stained positively anticytokeratin, The titer ofrAAV-LacZ was 2.1 × 108 virus particles/ml, 42% cultured human IPE cells expressedβ-galactosidase 7 days after transfection and 67% after 14 days.Conclusions: Recombined AAV produced without helper virus can transfer a foreign geneinto human IPE cells with high efficiency in vitro.

  8. Comparison of antioxidation systems of retinal pigment epithelium of pigmented and albino animals

    Energy Technology Data Exchange (ETDEWEB)

    Sakina, N.L.; Dontsov, A.E.; Ostrovskiy, M.A.

    1985-01-01

    The effectiveness of the lipid peroxidation inhibition process by tissue homogenates of retinal pigment epithelium of pigmented rabbits is higher than that of albino rabbits. The superoxide dismutase and glutathione perioxidase activity is nearly the same in both tissues of the pigment epithelium, the ..cap alpha..-tocopherol content is higher in retinal pigment epithelium tissue of albino animals, and the oxidizability of the lipid fraction of pigment epithelium tissue is higher in pigmented animals than in albinos. It is concluded that the higher resistance of the pigment epithelium of pigmented animals to the effects of prooxidant systems is due to the presence of melanoprotein granules in the pigment epithelium.

  9. The impact of cHS4 insulators on DNA transposon vector mobilization and silencing in retinal pigment epithelium cells.

    Directory of Open Access Journals (Sweden)

    Nynne Sharma

    Full Text Available DNA transposons have become important vectors for efficient non-viral integration of transgenes into genomic DNA. The Sleeping Beauty (SB, piggyBac (PB, and Tol2 transposable elements have distinct biological properties and currently represent the most promising transposon systems for animal transgenesis and gene therapy. A potential obstacle, however, for persistent function of integrating vectors is transcriptional repression of the element and its genetic cargo. In this study we analyze the insulating effect of the 1.2-kb 5'-HS4 chicken β-globin (cHS4 insulator element in the context of SB, PB, and Tol2 transposon vectors. By examining transgene expression from genomically inserted transposon vectors encoding a marker gene driven by a silencing-prone promoter, we detect variable levels of transcriptional silencing for the three transposon systems in retinal pigment epithelium cells. Notably, the PB system seems less vulnerable to silencing. Incorporation of cHS4 insulator sequences into the transposon vectors results in 2.2-fold and 1.5-fold increased transgene expression levels for insulated SB and PB vectors, respectively, but an improved persistency of expression was not obtained for insulated transgenes. Colony formation assays and quantitative excision assays unveil enhanced SB transposition efficiencies by the inclusion of the cHS4 element, resulting in a significant increase in the stable transfection rate for insulated SB transposon vectors in human cell lines. Our findings reveal a positive impact of cHS4 insulator inclusion for SB and PB vectors in terms of increased transgene expression levels and improved SB stable transfection rates, but also the lack of a long-term protective effect of the cHS4 insulator against progressive transgene silencing in retinal pigment epithelium cells.

  10. Effects of vegetable oils on biochemical and biophysical properties of membrane retinal pigment epithelium cells.

    Science.gov (United States)

    Said, Toihiri; Tremblay-Mercier, Jennifer; Berrougui, Hicham; Rat, Patrice; Khalil, Abdelouahed

    2013-10-01

    The aim of this study was to investigate the effect of vegetable oil enrichment of retinal pigment epithelial (RPE) cells on their biochemical and biophysical properties. For this, RPE cells were incubated with 4 different vegetables oils (olive oil, corn oil, argan oil, and camelina oil). The cytotoxicity of these vegetable oils was assessed in vivo on 8-week-old mice and in vitro by using the neutral red and YO-PRO-1 tests. Membrane fluidity was evaluated by fluorescence anisotropy using the fluorescent probe diphenylhexatriene, and membrane fatty acid composition was assessed by gas chromatography. None of the oils tested displayed cytotoxic effects. In vitro, omega-3 rich oils improved membrane fluidity by 47% compared with the control cells. The omega-3 PUFA content within membranes decreased by 38% to 55% when cells were incubated separately with olive oil, corn oil, or argan oil, and increased when cells were incubated with a mixture of those oils, or with camelina oil alone (50% and 103% increase, respectively). Our results show that the fatty acids in vegetable oil incorporate into retinal cells and increase the plasma membrane fluidity.

  11. Neoplasia versus hyperplasia of the retinal pigment epithelium

    DEFF Research Database (Denmark)

    Heegaard, Steffen; Larsen, J.N.B.; Fledelius, Hans C.

    2001-01-01

    ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography......ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography...

  12. Deriving retinal pigment epithelium (RPE) from induced pluripotent stem (iPS) cells by different sizes of embryoid bodies.

    Science.gov (United States)

    Muñiz, Alberto; Ramesh, Kaini R; Greene, Whitney A; Choi, Jae-Hyek; Wang, Heuy-Ching

    2015-02-04

    Pluripotent stem cells possess the ability to proliferate indefinitely and to differentiate into almost any cell type. Additionally, the development of techniques to reprogram somatic cells into induced pluripotent stem (iPS) cells has generated interest and excitement towards the possibility of customized personal regenerative medicine. However, the efficiency of stem cell differentiation towards a desired lineage remains low. The purpose of this study is to describe a protocol to derive retinal pigment epithelium (RPE) from iPS cells (iPS-RPE) by applying a tissue engineering approach to generate homogenous populations of embryoid bodies (EBs), a common intermediate during in vitro differentiation. The protocol applies the formation of specific size of EBs using microwell plate technology. The methods for identifying protein and gene markers of RPE by immunocytochemistry and reverse-transcription polymerase chain reaction (RT-PCR) are also explained. Finally, the efficiency of differentiation in different sizes of EBs monitored by fluorescence-activated cell sorting (FACS) analysis of RPE markers is described. These techniques will facilitate the differentiation of iPS cells into RPE for future applications.

  13. Glycosaminoglycans in human retinoblastoma cells: Heparan sulfate, a modulator of the pigment epithelium-derived factor-receptor interactions

    Science.gov (United States)

    Alberdi, Elena M; Weldon, John E; Becerra, S Patricia

    2003-01-01

    Background Pigment epithelium-derived factor (PEDF) has binding affinity for cell-surface receptors in retinoblastoma cells and for glycosaminoglycans. We investigated the effects of glycosaminoglycans on PEDF-receptor interactions. Results 125I-PEDF formed complexes with protease-resistant components of medium conditioned by human retinoblastoma Y-79 cells. Using specific glycosaminoglycan degrading enzymes in spectrophotometric assays and PEDF-affinity chromatography, we detected heparin and heparan sulfate-like glycosaminoglycans in the Y-79 conditioned media, which had binding affinity for PEDF. The Y-79 conditioned media significantly enhanced the binding of 125I-PEDF to Y-79 cell-surface receptors. However, enzymatic and chemical depletion of sulfated glycosaminoglycans from the Y-79 cell cultures by heparitinase and chlorate treatments decreased the degree of 125I-PEDF binding to cell-surface receptors. Conclusions These data indicate that retinoblastoma cells secrete heparin/heparan sulfate with binding affinity for PEDF, which may be important in efficient cell-surface receptor binding. PMID:12625842

  14. JAM-C maintains VEGR2 expression to promote retinal pigment epithelium cell survival under oxidative stress.

    Science.gov (United States)

    Jia, Xin; Zhao, Chen; Chen, Qishan; Du, Yuxiang; Huang, Lijuan; Ye, Zhimin; Ren, Xiangrong; Wang, Shasha; Lee, Chunsik; Tang, Zhongshu; Li, Xuri; Ju, Rong

    2017-04-03

    Junctional adhesion molecule-C (JAM-C) has been shown to play critical roles during development and in immune responses. However, its role in adult eyes under oxidative stress remains poorly understood. Here, we report that JAM-C is abundantly expressed in adult mouse retinae and choroids in vivo and in cultured retinal pigment epithelium (RPE) and photoreceptor cells in vitro. Importantly, both JAM-C expression and its membrane localisation are downregulated by H2O2-induced oxidative stress. Under H2O2-induced oxidative stress, JAM-C is critically required for the survival of human RPE cells. Indeed, loss of JAM-C by siRNA knockdown decreased RPE cell survival. Mechanistically, we show that JAM-C is required to maintain VEGFR2 expression in RPE cells, and VEGFR2 plays an important role in keeping the RPE cells viable since overexpression of VEGFR2 partially restored impaired RPE survival caused by JAM-C knockdown and increased RPE survival. We further show that JAM-C regulates VEGFR2 expression and, in turn, modulates p38 phosphorylation. Together, our data demonstrate that JAM-C plays an important role in maintaining VEGR2 expression to promote RPE cell survival under oxidative stress. Given the vital importance of RPE in the eye, approaches that can modulate JAM-C expression may have therapeutic values in treating diseases with impaired RPE survival.

  15. Protective effects of human iPS-derived retinal pigment epithelium cell transplantation in the retinal dystrophic rat.

    Directory of Open Access Journals (Sweden)

    Amanda-Jayne Carr

    Full Text Available Transformation of somatic cells with a set of embryonic transcription factors produces cells with the pluripotent properties of embryonic stem cells (ESCs. These induced pluripotent stem (iPS cells have the potential to differentiate into any cell type, making them a potential source from which to produce cells as a therapeutic platform for the treatment of a wide range of diseases. In many forms of human retinal disease, including age-related macular degeneration (AMD, the underlying pathogenesis resides within the support cells of the retina, the retinal pigment epithelium (RPE. As a monolayer of cells critical to photoreceptor function and survival, the RPE is an ideally accessible target for cellular therapy. Here we report the differentiation of human iPS cells into RPE. We found that differentiated iPS-RPE cells were morphologically similar to, and expressed numerous markers of developing and mature RPE cells. iPS-RPE are capable of phagocytosing photoreceptor material, in vitro and in vivo following transplantation into the Royal College of Surgeons (RCS dystrophic rat. Our results demonstrate that iPS cells can be differentiated into functional iPS-RPE and that transplantation of these cells can facilitate the short-term maintenance of photoreceptors through phagocytosis of photoreceptor outer segments. Long-term visual function is maintained in this model of retinal disease even though the xenografted cells are eventually lost, suggesting a secondary protective host cellular response. These findings have identified an alternative source of replacement tissue for use in human retinal cellular therapies, and provide a new in vitro cellular model system in which to study RPE diseases affecting human patients.

  16. Functional annotation of the human retinal pigment epithelium transcriptome

    NARCIS (Netherlands)

    J.C. Booij (Judith); S. van Soest (Simone); S.M.A. Swagemakers (Sigrid); A.H.W. Essing (Anke); J.H.M. Verkerk (Annemieke); P.J. van der Spek (Peter); T.G.M.F. Gorgels (Theo); A.A.B. Bergen (Arthur)

    2009-01-01

    textabstractBackground: To determine level, variability and functional annotation of gene expression of the human retinal pigment epithelium (RPE), the key tissue involved in retinal diseases like age-related macular degeneration and retinitis pigmentosa. Macular RPE cells from six selected healthy

  17. Functional annotation of the human retinal pigment epithelium transcriptome

    NARCIS (Netherlands)

    Booij, J.C.; van Soest, S.; Swagemakers, S.M.A.; Essing, A.H.W.; Verkerk, A.J.M.H.; van der Spek, P.J.; Gorgels, T.G.M.F.; Bergen, A.A.B.

    2009-01-01

    ABSTRACT: BACKGROUND: To determine level, variability and functional annotation of gene expression of the human retinal pigment epithelium (RPE), the key tissue involved in retinal diseases like age-related macular degeneration and retinitis pigmentosa. Macular RPE cells from six selected healthy hu

  18. Effects of Nerve Growth Factor on Proliferation and DNA Synthesis of Cultured Human Fetal Retinal Pigment Epithelium Cells

    Institute of Scientific and Technical Information of China (English)

    Wensheng Li; Jun Wen; Deyong Jiang; Jianguang Ding

    2002-01-01

    Objective: To investigate the effects of nerve growth factor(NGF)on proliferation and DNAthesis of cultured human fetal retinal pigment epithelium (RPE)cells in vitro.Methods: Primary culture and subculture of human fetal retinal pigment epithelium cellswere established in vitro first. Cultured RPE cells were treated with NGF by variousconcentrations 0μg/L, 50μg/L, 100μg/L, 200μg/L and 300μg/L(final concentration)for 48 hs.After 48 hs, cells proliferation was measured with methyl thiazolyl tetrazolium(MTT)assay method and the amount of DNA was determined by the absorbance at 280nm of nucleic acid & protein analysis.Results: The A values of 100 μg/L, 200 μg/L, 300 μg/L NGF was(0. 213 7 ± 0. 23 3),(0. 218 8 ±0. 018 1), (0. 232 2 ±0. 016 4) as compared with(0. 189 7 ±0. 015 2) of Avalue of 0 μg/L NGF respectively, q value was 3.63,4.40, 6. 42 and P value was0. 015, 0. 000, 0. 000(q-test). The DNA concentrations of 100 μg/L, 200 μg/L, 300μg/L and 400 μg/L NGF was (981. 220 4 ± 123.535 7), (1 375. 848 4 ±244. 471 8),(1 658.707 1 ± 176. 938 1), (2 353.086 3 ±609. 906 4) μg/ml as compared with(666. 818 8 ± 141. 330 2) μg/ml of DNA concentration of 0 μg/L NGF respectively, qvalue was 3.63,8.20,11.47,19.46, P value was 0. 024,0. 000,0. 000,0. 000 (q-test).Conclusion: The data suggested that NGF could stimulate the proliferation and DNAsynthesis of cultured of hRPE cells in vitro in a dose-dependent manner.

  19. ROCK Inhibition Promotes Attachment, Proliferation, and Wound Closure in Human Embryonic Stem Cell-Derived Retinal Pigmented Epithelium.

    Science.gov (United States)

    Croze, Roxanne H; Thi, William J; Clegg, Dennis O

    2016-11-01

    Nonexudative (dry) age-related macular degeneration (AMD), a leading cause of blindness in the elderly, is associated with the loss of retinal pigmented epithelium (RPE) cells and the development of geographic atrophy, which are areas devoid of RPE cells and photoreceptors. One possible treatment option would be to stimulate RPE attachment and proliferation to replace dying/dysfunctional RPE and bring about wound repair. Clinical trials are underway testing injections of RPE cells derived from pluripotent stem cells to determine their safety and efficacy in treating AMD. However, the factors regulating RPE responses to AMD-associated lesions are not well understood. Here, we use cell culture to investigate the role of RhoA coiled coil kinases (ROCKs) in human embryonic stem cell-derived RPE (hESC-RPE) attachment, proliferation, and wound closure. H9 hESC were spontaneously differentiated into RPE cells. hESC-RPE cells were treated with a pan ROCK1/2 or a ROCK2 only inhibitor; attachment, and proliferation and cell size within an in vitro scratch assay were examined. Pharmacological inhibition of ROCKs promoted hESC-RPE attachment and proliferation, and increased the rate of closure of in vitro wounds. ROCK inhibition decreased phosphorylation of cofilin and myosin light chain, suggesting that regulation of the cytoskeleton underlies the mechanism of action of ROCK inhibition. ROCK inhibition promotes attachment, proliferation, and wound closure in H9 hESC-RPE cells. ROCK isoforms may have different roles in wound healing. Modulation of the ROCK-cytoskeletal axis has potential in stimulating wound repair in transplanted RPE cells and attachment in cellular therapies.

  20. Retinal pigment epithelium cell-derived exosomes: Possible relevance to CNV in wet-age related macular degeneration.

    Science.gov (United States)

    Tong, Yao; Zhou, Ya-Li; Wang, Yi-Xiao; Zhao, Pei-Quan; Wang, Zhao-Yang

    2016-12-01

    Exosomes are small vesicles that are released by almost every cell type and play a crucial role in many physiological and pathological processes associated with different diseases. Specifically, they promote angiogenesis in the pathogenesis of some diseases. According to previous research, the proteins of exosomes taken from the aqueous humor (AH) of patients with wet-age related macular degeneration (AMD) may function as a new diagnostic biomarker of AMD, suggesting that exosomes may play an important role in the occurrence and development of choroidal neovascularization (CNV). Moreover, additional research has revealed that the levels of some protein makers of exosomes are up-regulated in aged retinal pigment epithelium (RPE) and that drusen and oxidative stress may promote the secretion of exosomes derived from RPE cells. Consequently, we hypothesize that RPE cell-derived exosomes may be relevant to CNV in wet AMD. If this hypothesis is proven correct, future studies based on this link may also help to elucidate the molecular mechanisms of wet AMD and to find new therapeutic targets for the treatment of AMD.

  1. Light-induced damage and its diagnosis in two-photon excited autofluorescence imaging of retinal pigment epithelium cells

    Science.gov (United States)

    Chen, Danni; Qu, Junle; Xu, Gaixia; Zhao, Lingling; Niu, Hanben

    2007-05-01

    In this paper, a novel method for the differentiation of the retinal pigment epithelium (RPE) cells after light-induced damage by two-photon excitation is presented. Fresh samples of RPE cells of pig eyes are obtained from local slaughterhouse. Light-induced damage is produced by the output from Ti: sapphire laser which is focused onto the RPE layer. We study the change of the autofluorescence properties of RPE after two-photon excitation with the same wavelength. Preliminary results show that after two-photon excitation, there are two clear changes in the emission spectrum. The first change is the blue-shift of the emission peak. The emission peak of the intact RPE is located at 592nm, and after excitation, it shifts to 540nm. It is supposed that the excitation has led to the increased autofluorescence of flavin whose emission peak is located at 540nm. The second change is the increased intensity of the emission peak, which might be caused by the accelerated aging because the autofluorescence of RPE would increase during aging process. Experimental results indicate that two-photon excitation could not only lead to the damage of the RPE cells in multiphoton RPE imaging, but also provide an evaluation of the light-induced damage.

  2. Developmental origin of the posterior pigmented epithelium of iris.

    Science.gov (United States)

    Wang, Xiaobing; Xiong, Kai; Lu, Lei; Gu, Dandan; Wang, Songtao; Chen, Jing; Xiao, Honglei; Zhou, Guomin

    2015-03-01

    Iris epithelium is a double-layered pigmented cuboidal epithelium. According to the current model, the neural retina and the posterior iris pigment epithelium (IPE) are derived from the inner wall of the optic cup, while the retinal pigment epithelium (RPE) and the anterior IPE are derived from the outer wall of the optic cup during development. Our current study shows evidence, contradicting this model of fetal iris development. We demonstrate that human fetal iris expression patterns of Otx2 and Mitf transcription factors are similar, while the expressions of Otx2 and Sox2 are complementary. Furthermore, IPE and RPE exhibit identical morphologic development during the early embryonic period. Our results suggest that the outer layer of the optic cup forms two layers of the iris epithelium, and the posterior IPE is the inward-curling anterior rim of the outer layer of the optic cup. These findings provide a reasonable explanation of how IPE cells can be used as an appropriate substitute for RPE cells.

  3. Recombinant human pigment epithelium-derived factor (PEDF): characterization of PEDF overexpressed and secreted by eukaryotic cells.

    Science.gov (United States)

    Stratikos, E.; Alberdi, E.; Gettins, P. G.; Becerra, S. P.

    1996-01-01

    Pigment epithelium-derived factor (PEDF) is a serpin found in the interphotoreceptor matrix of the eye, which, although not a proteinase inhibitor, possesses a number of important biological properties, including promotion of neurite outgrowth and differential expression in quiescent versus senescent states of certain cell types. The low amounts present in the eye, together with the impracticality of using the eye as a source for isolation of the human protein, make it important to establish a system for overexpression of the recombinant protein for biochemical and biological studies. We describe here the expression and secretion of full-length glycosylated human recombinant PEDF at high levels (> 20 micrograms/ mL) into the growth medium of baby hamster kidney cells and characterization of the purified rPEDF by circular dichroism and fluorescence spectroscopies and neurite outgrowth assay. By these assays, the recombinant protein behaves as expected for a correctly folded full-length human PEDF. The availability of milligram amounts of PEDF has permitted quantitation of its heparin binding properties and of the effect of reactive center cleavage on the stability of PEDF towards thermal and guanidine hydrochloride denaturation. PMID:8976566

  4. Inhibition of autophagy suppresses sertraline-mediated primary ciliogenesis in retinal pigment epithelium cells.

    Science.gov (United States)

    Kim, Eun Sung; Shin, Ji Hyun; Park, So Jung; Jo, Yoon Kyung; Kim, Jae-Sung; Kang, Il-Hwan; Nam, Jung-Bum; Chung, Doo-Young; Cho, Yoonchul; Lee, EunJoo H; Chang, Jong Wook; Cho, Dong-Hyung

    2015-01-01

    Primary cilia are conserved cellular organelles that regulate diverse signaling pathways. Autophagy is a complex process of cellular degradation and recycling of cytoplasmic proteins and organelles, and plays an important role in cellular homeostasis. Despite its potential importance, the role of autophagy in ciliogenesis is largely unknown. In this study, we identified sertraline as a regulator of autophagy and ciliogenesis. Sertraline, a known antidepressant, induced the growth of cilia and blocked the disassembly of cilia in htRPE cells. Following treatment of sertraline, there was an increase in the number of cells with autophagic puncta and LC3 protein conversion. In addition, both a decrease of ATG5 expression and the treatment of an autophagy inhibitor resulted in the suppression of the sertraline-induced activation of autophagy in htRPE cells. Interestingly, we found that genetic and chemical inhibition of autophagy attenuated the growth of primary cilia in htRPE cells. Taken together, our results suggest that the inhibition of autophagy suppresses sertraline-induced ciliogenesis.

  5. In vivo imaging of retinal pigment epithelium cells in age related macular degeneration.

    Science.gov (United States)

    Rossi, Ethan A; Rangel-Fonseca, Piero; Parkins, Keith; Fischer, William; Latchney, Lisa R; Folwell, Margaret A; Williams, David R; Dubra, Alfredo; Chung, Mina M

    2013-01-01

    Morgan and colleagues demonstrated that the RPE cell mosaic can be resolved in the living human eye non-invasively by imaging the short-wavelength autofluorescence using an adaptive optics (AO) ophthalmoscope. This method, based on the assumption that all subjects have the same longitudinal chromatic aberration (LCA) correction, has proved difficult to use in diseased eyes, and in particular those affected by age-related macular degeneration (AMD). In this work, we improve Morgan's method by accounting for chromatic aberration variations by optimizing the confocal aperture axial and transverse placement through an automated iterative maximization of image intensity. The increase in image intensity after algorithmic aperture placement varied depending upon patient and aperture position prior to optimization but increases as large as a factor of 10 were observed. When using a confocal aperture of 3.4 Airy disks in diameter, images were obtained using retinal radiant exposures of less than 2.44 J/cm(2), which is ~22 times below the current ANSI maximum permissible exposure. RPE cell morphologies that were strikingly similar to those seen in postmortem histological studies were observed in AMD eyes, even in areas where the pattern of fluorescence appeared normal in commercial fundus autofluorescence (FAF) images. This new method can be used to study RPE morphology in AMD and other diseases, providing a powerful tool for understanding disease pathogenesis and progression, and offering a new means to assess the efficacy of treatments designed to restore RPE health.

  6. Reduced Expression of Cytoskeletal and Extracellular Matrix Genes in Human Adult Retinal Pigment Epithelium Cells Exposed to Simulated Microgravity

    DEFF Research Database (Denmark)

    Corydon, Thomas J; Mann, Vivek; Slumstrup, Lasse;

    2016-01-01

    BACKGROUND/AIMS: Microgravity (µg) has adverse effects on the eye of humans in space. The risk of visual impairment is therefore one of the leading health concerns for NASA. The impact of µg on human adult retinal epithelium (ARPE-19) cells is unknown. METHODS: In this study we investigated the i...

  7. The Developmental Stage of Adult Human Stem Cell-Derived Retinal Pigment Epithelium Cells Influences Transplant Efficacy for Vision Rescue

    Directory of Open Access Journals (Sweden)

    Richard J. Davis

    2017-07-01

    Full Text Available Age-related macular degeneration (AMD is a common cause of central visual loss in the elderly. Retinal pigment epithelial (RPE cell loss occurs early in the course of AMD and RPE cell transplantation holds promise to slow disease progression. We report that subretinal transplantation of RPE stem cell (RPESC-derived RPE cells (RPESC-RPE preserved vision in a rat model of RPE cell dysfunction. Importantly, the stage of differentiation that RPESC-RPE acquired prior to transplantation influenced the efficacy of vision rescue. Whereas cells at all stages of differentiation tested rescued photoreceptor layer morphology, an intermediate stage of RPESC-RPE differentiation obtained after 4 weeks of culture was more consistent at vision rescue than progeny that were differentiated for 2 weeks or 8 weeks of culture. Our results indicate that the developmental stage of RPESC-RPE significantly influences the efficacy of RPE cell replacement, which affects the therapeutic application of these cells for AMD.

  8. Human Bone Marrow Stromal Cells can Differentiate to a Retinal Pigment Epithelial Phenotype when Co-Cultured with Pig Retinal Pigment Epithelium using a Transwell System

    Directory of Open Access Journals (Sweden)

    Ping Duan

    2013-05-01

    Full Text Available Background: There is an increasing interest in generating retinal pigment epithelial (RPE cells from stem cells for therapy against degenerative eye diseases. Human bone marrow stromal cells (hBMSCs can be induced to express retinal neuron-specific markers when co-cultured with retinal neurons, however, whether hBMSCs can differentiate into RPE-like cells in a co-culture system has not been clarified. Methods: The induction of hBMSCs into RPE-like cells was performed by combining hBMSCs and pig RPE cells in a transwell system. The biomarkers of hBMSCs-derived RPE cells were determined by quantitative RT-PCR and immunofluorescence. The function of induced cells was assayed by ELISA for secretion of neurotrophic factors. Results: Intracellular pigment granules and many RPE markers existed in hBMSCs-derived RPE cells after co-culturing with pig RPE cells for 14 days. Typical RPE functions, such as phagocytosis of photoreceptor outer segments and secretion of the trophic factors, brain-derived neurotrophic factor (BDNF and glia-derived neurotrophic factor (GDNF, were observed in these induced cells. Conclusion: hBMSCs can be induced toward functional RPE cells simply by transwell-based co-culture with RPE cells.

  9. Glucose metabolism in rat retinal pigment epithelium.

    Science.gov (United States)

    Coffe, Víctor; Carbajal, Raymundo C; Salceda, Rocío

    2006-01-01

    The retinal pigment epithelium (RPE) is the major transport pathway for exchange of metabolites and ions between choroidal blood supply and the neural retina. To gain insight into the mechanisms controlling glucose metabolism in RPE and its possible relationship to retinopathy, we studied the influence of different glucose concentrations on glycogen and lactate levels and CO(2) production in RPE from normal and streptozotocin-treated diabetic rats. Incubation of normal RPE in the absence of glucose caused a decrease in lactate production and glycogen content. In normal RPE, increasing glucose concentrations from 5.6 mM to 30 mM caused a four-fold increase in glucose accumulation and CO(2) yield, as well as reduction in lactate and glycogen production. In RPE from diabetic rats glucose accumulation did not increase in the presence of high glucose substrate, but it showed a four- and a seven-fold increase in CO(2) production through the mitochondrial and pentose phosphate pathways, respectively. We found high glycogen levels in RPE which can be used as an energy reserve for RPE itself and/or neural retina. Findings further show that the RPE possesses a high oxidative capacity. The large increase in glucose shunting to the pentose phosphate pathway in diabetic retina exposed to high glucose suggests a need for reducing capacity, consistent with increased oxidative stress.

  10. Detachments of the retinal pigment epithelium at the posterior pole.

    Science.gov (United States)

    Noble, K G; Levitzky, M J; Carr, R E

    1976-08-01

    Multiple vitelliform cysts of the retina, a disorder of unknown cause in which there are multiple detachments of the retinal pigment epithelium at the posterior pole, occurred in five patients. In four patients all lesions were located outside the parafoveal area while one patient showed bilateral foveal elevations associated with more eccentric detachments. Several patients showed slow resolution of some of the detachments with mild disturbances of the pigment epithelium.

  11. Druse-Induced Morphology Evolution in Retinal Pigment Epithelium

    CERN Document Server

    Mazzitello, K I; Chrenek, M A; Family, F; Grossniklaus, H E; Nickerson, J M; Jiang, Y

    2016-01-01

    The retinal pigment epithelium (RPE) is a key site of pathogenesis for many retina diseases. The formation of drusen in the retina is characteristic of retinal degeneration. We investigate morphological changes in the RPE in the presence of soft drusen using an integrated experimental and modeling approach. We collect RPE flat mount images from donated human eyes and develop 1) statistical tools to quantify the images and 2) a cell-based model to simulate the morphology evolution. We compare three different mechanisms of RPE repair evolution, cell apoptosis, cell fusion, and expansion, and Simulations of our RPE morphogenesis model quantitatively reproduce deformations of human RPE morphology due to drusen, suggesting that a purse-string mechanism is sufficient to explain how RPE heals cell loss caused by drusen-damage. We found that drusen beneath tissue promote cell death in a number that far exceeds the cell numbers covering the drusen. Tissue deformations are studied using area distributions, Voronoi doma...

  12. Complement Factor H Expressed by Retinal Pigment Epithelium Cells Can Suppress Neovascularization of Human Umbilical Vein Endothelial Cells: An in vitro Study.

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    Full Text Available Complement factor H (CFH is one of the most important soluble complement regulatory proteins and is closely associated with age-related macular degeneration (AMD, the leading cause of irreversible central vision loss in the elderly population in developed countries. Our study searches to investigate whether CFH expression is changed in oxidative damaged retinal pigment epithelium (RPE cells and the role of CFH in the in vitro neovascularization. First, it was confirmed by immunofluorescence staining that CFH was expressed by ARPE-19 cells. CFH mRNA and protein in oxidative (H2O2 damaged ARPE-19 cells were both reduced, as determined by Real-time PCR and Western blotting analysis. Enzyme-linked immunosorbent assay (ELISA also showed that ARPE-19 cells treated with H2O2 caused an increase in C3a content, which indicates complement activation. Then, wound assays were performed to show that CFH expression suppression promoted human umbilical vein endothelial cell (HUVECs migration. Thereafter, ARPE-19 cells were transfected with CFH-specific siRNA and CFH knockdown was confirmed with the aid of Real-time PCR, immunofluorescence staining and Western blotting. The ELISA results showed that specific CFH knockdown in ARPE-19 cells activated the complement system. Finally, in vitro matrigel tube formation assay was performed to determine whether change of CFH expression in RPE would affect tube formation by HUVECs. More tubes were formed by HUVECs co-cultured with ARPE-19 cells transfected with CFH specific-siRNA when compared with controls. Our results suggested that RPE cells might be the local CFH source, and RPE cell injuries (such as oxidative stress may cause CFH expression suppression, which in turn may lead to complement activation and promotion of tube formation by HUVECs. This finding is of importance in elucidating the role of complement in the pathogenesis of ocular neovascularization including choroidal neovascularization.

  13. Adenoviral E4 Gene Stimulates Secretion of Pigmental Epithelium Derived Factor (PEDF) that Maintains Long-term Survival of Human Glomerulus-derived Endothelial Cells*

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    Jerebtsova, Marina; Kumari, Namita; Obuhkov, Yuri; Nekhai, Sergei

    2012-01-01

    Renal glomerular endothelial cells are specialized cells with an important role in physiological filtration and glomerular disease. However, maintenance of human primary endothelial cells requires stimulation with serum and growth factors that often results in modification of the cells properties. Previously, expression of early adenovirus region E4 was shown to help maintaining long-term survival of human endothelial cells in serum free media without addition of growth factors. In the current study, we showed that media conditioned with human epithelial cells stably transfected with Ad E4 region also supported survival of human glomerulus-derived endothelial cells in serum-free media. Mass-spectrometry analysis of the conditioned media identified pigmental epithelium derived factor (PEDF) as a major component of the conditioned media. PEDF expression in 293-E4 cells was validated by RT-PCR, Western blot and ELISA analysis. PEDF expression was detected in mouse glomeruli. Supplementation with recombinant PEDF supported survival of primary endothelial cells and the cells transformed with SV40 large T antigen in serum-free media, and extended the life-span of both cell cultures. PEDF did not inhibit FGF-2 stimulated growth and tubulogenesis of endothelial cells. Thus we demonstrated that adenoviral E4 region stimulated expression and secretion of PEDF by human renal epithelial cells that acted as a survival factor for glomerulus-derived endothelial cells. PMID:22915824

  14. From confluent human iPS cells to self-forming neural retina and retinal pigmented epithelium.

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    Reichman, Sacha; Terray, Angélique; Slembrouck, Amélie; Nanteau, Céline; Orieux, Gaël; Habeler, Walter; Nandrot, Emeline F; Sahel, José-Alain; Monville, Christelle; Goureau, Olivier

    2014-06-10

    Progress in retinal-cell therapy derived from human pluripotent stem cells currently faces technical challenges that require the development of easy and standardized protocols. Here, we developed a simple retinal differentiation method, based on confluent human induced pluripotent stem cells (hiPSC), bypassing embryoid body formation and the use of exogenous molecules, coating, or Matrigel. In 2 wk, we generated both retinal pigmented epithelial cells and self-forming neural retina (NR)-like structures containing retinal progenitor cells (RPCs). We report sequential differentiation from RPCs to the seven neuroretinal cell types in maturated NR-like structures as floating cultures, thereby revealing the multipotency of RPCs generated from integration-free hiPSCs. Furthermore, Notch pathway inhibition boosted the generation of photoreceptor precursor cells, crucial in establishing cell therapy strategies. This innovative process proposed here provides a readily efficient and scalable approach to produce retinal cells for regenerative medicine and for drug-screening purposes, as well as an in vitro model of human retinal development and disease.

  15. Reduced Expression of Cytoskeletal and Extracellular Matrix Genes in Human Adult Retinal Pigment Epithelium Cells Exposed to Simulated Microgravity

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    Thomas J. Corydon

    2016-11-01

    Full Text Available Background/Aims: Microgravity (µg has adverse effects on the eye of humans in space. The risk of visual impairment is therefore one of the leading health concerns for NASA. The impact of µg on human adult retinal epithelium (ARPE-19 cells is unknown. Methods: In this study we investigated the influence of simulated µg (s-µg; 5 and 10 days (d, using a Random Positioning Machine (RPM, on ARPE-19 cells. We performed phase-contrast/fluorescent microscopy, qRT-PCR, Western blotting and pathway analysis. Results: Following RPM-exposure a subset of ARPE-19 cells formed multicellular spheroids (MCS, whereas the majority of the cells remained adherent (AD. After 5d, alterations of F-actin and fibronectin were observed which reverted after 10d-exposure, suggesting a time-dependent adaptation to s-µg. Gene expression analysis of 12 genes involved in cell structure, shape, adhesion, migration, and angiogenesis suggested significant changes after a 10d-RPM-exposure. 11 genes were down-regulated in AD and MCS 10d-RPM-samples compared to 1g, whereas FLK1 was up-regulated in 5d- and 10d-RPM-MCS-samples. Similarly, TIMP1 was up-regulated in 5d-RPM-samples, whereas the remaining genes were down-regulated in 5d-RPM-samples. Western blotting revealed similar changes in VEGF, β-actin, laminin and fibronectin of 5d-RPM-samples compared to 10d, whereas different alterations of β-tubulin and vimentin were observed. The pathway analysis showed complementing effects of VEGF and integrin β-1. Conclusions: These findings clearly show that s-µg induces significant alterations in the F-actin-cytoskeleton and cytoskeleton-related proteins of ARPE-19, in addition to changes in cell growth behavior and gene expression patterns involved in cell structure, growth, shape, migration, adhesion and angiogenesis.

  16. Comparing three methods of co-culture of retinal pigment epithelium with progenitor cells derived human embryonic stem cells

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    Noushin Amirpour

    2013-01-01

    The adherent cells were morphologically examined using phase contrast microscopy and characterized by immunofluorescent staining and reverse transcription-polymerase chain reaction (RT-PCR Results: Evaluation of immunostaining showed that hESC, highly (>80% can be directed to the RPs fate. Upon co-culture of RPCs with RPE sheet using insert for 2 weeks or by the cell-to-cell contact, these cells differentiated to neural retina and expressed photoreceptor-specific markers. However, in direct co-culture, some mature photoreceptor markers like arrestin expressed in compare with indirect co-culture. Conclusions: The expression of late photoreceptor marker could be improved when RPE cells seeded on RPCs in compare with the use of insert.

  17. Inhibition by miR-410 facilitates direct retinal pigment epithelium differentiation of umbilical cord blood-derived mesenchymal stem cells

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    Choi, Soon Won; Kim, Jae-Jun; Seo, Min-Soo; Park, Sang-Bum; Shin, Tae-Hoon; Shin, Ji-Hee; Seo, Yoojin; Kim, Hyung-Sik

    2017-01-01

    Retinal pigment epithelium (RPE) is a major component of the eye. This highly specialized cell type facilitates maintenance of the visual system. Because RPE loss induces an irreversible visual impairment, RPE generation techniques have recently been investigated as a potential therapeutic approach to RPE degeneration. The microRNA-based technique is a new strategy for producing RPE cells from adult stem cell sources. Previously, we identified that antisense microRNA-410 (anti-miR-410) induces RPE differentiation from amniotic epithelial stem cells. In this study, we investigated RPE differentiation from umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) via anti-miR-410 treatment. We identified miR-410 as a RPE-relevant microRNA in UCB-MSCs from among 21 putative human RPE-depleted microRNAs. Inhibition of miR-410 induces overexpression of immature and mature RPE-specific factors, including MITF, LRAT, RPE65, Bestrophin, and EMMPRIN. The RPE-induced cells were able to phagocytize microbeads. Results of our microRNA-based strategy demonstrated proof-of-principle for RPE differentiation in UCB-MSCs by using anti-miR-410 treatment without the use of additional factors or exogenous transduction. PMID:27297412

  18. Pathological, Ultrastructural and Immunohistochemical Observations of Adenoma of Retinal Pigment Epithelium

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    Ping Zhang; Guanguang Feng; Tao Yue; Jianxian Lin; Yuzhen Yi; Youjian Pang

    2001-01-01

    Purpose: To Study the clinical, pathological, ultrastructural and immunohistchemicalcharacters of adenoma of the retinal pigment epithelium in order to offer evidence todiagnose this tumor.Methods: Routine paraffin slices HE stain, histochemistry PAS and VG stain,transmission electron microscopy, and immunohistochemistry for S-100 and vimentinwith LSAB method were used.Results: The tumor cells were oval and cuboidal in shape. Part of the tumor had atubular arrangement. Around the sheets of tumors cells there was a large amount ofuniform red stick-like substances. The above matter represented positive in PAS stain.Most of the above matter was yellow, while less of the matter showed red in VG stain.Transmission electron microscopy showed that there were tight junctions between tumorcells. Immunohistochemistry showed positive for S-100, negative for vimentin.Conclusions: The ultrastructural and immunohistochemical characters of the adenoma ofretinal pigment epithelium are consistent with the retinal pigment epithelium.

  19. Role of pigment epithelium-derived factor in the involution of hemangioma: Autocrine growth inhibition of hemangioma-derived endothelial cells

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    Kim, Kyung-Jin [Department of Pharmacology, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of); Department of Biomedical Science, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of); Yun, Jang-Hyuk; Heo, Jong-Ik [Department of Pharmacology, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of); Lee, Eun Hui [Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Min, Hye Sook [Department of Pathology, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of); Choi, Tae Hyun, E-mail: psthchoi@snu.ac.kr [Department of Plastic and Reconstructive Surgery, Seoul National University Children’s Hospital, Seoul 110-744 (Korea, Republic of); Department of Pediatric Plastic and Reconstructive Surgery, Seoul National University Children’s Hospital, Seoul 110-744 (Korea, Republic of); Cho, Chung-Hyun, E-mail: iamhyun@snu.ac.kr [Department of Pharmacology, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of); Department of Biomedical Science, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of); Ischemic/Hypoxic Disease Institute, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of); Cancer Research Institute, College of Medicine, Seoul National University, Seoul 110-799 (Korea, Republic of)

    2014-11-14

    Highlights: • PEDF was expressed and induced during the involuting phase of IH. • PEDF inhibited the cell growth of the involuting HemECs in an autocrine manner. • PEDF suppression restored the impaired cell growth of the involuting HemECs. - Abstract: Hemangioma is a benign tumor derived from abnormal blood vessel growth. Unlike other vascular tumor counterparts, a hemangioma is known to proliferate during its early stage but it is followed by a stage of involution where regression of the tumor occurs. The critical onset leading to the involution of hemangioma is currently not well understood. This study focused on the molecular identities of the involution of hemangioma. We demonstrated that a soluble factor released from the involuting phase of hemangioma-derived endothelial cells (HemECs) and identified pigment epithelium-derived factor (PEDF) as an anti-angiogenic factor that was associated with the growth inhibition of the involuting HemECs. The growth inhibition of the involuting HemECs was reversed by suppression of PEDF in the involuting HemECs. Furthermore, we found that PEDF was more up-regulated in the involuting phase of hemangioma tissues than in the proliferating or the involuted. Taken together, we propose that PEDF accelerates the involution of hemangioma by growth inhibition of HemECs in an autocrine manner. The regulatory mechanism of PEDF expression could be a potential therapeutic target to treat hemangiomas.

  20. Pigment epithelium derived factor inhibits the growth of human endometrial implants in nude mice and of ovarian endometriotic stromal cells in vitro.

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    Yanmei Sun

    Full Text Available Angiogenesis is a prerequisite for the formation and development of endometriosis. Pigment epithelium derived factor (PEDF is a natural inhibitor of angiogenesis. We previously demonstrated a reduction of PEDF in the peritoneal fluid, serum and endometriotic lesions from women with endometriosis compared with women without endometriosis. Here, we aim to investigate the inhibitory effect of PEDF on human endometriotic cells in vivo and in vitro. We found that PEDF markedly inhibited the growth of human endometrial implants in nude mice and of ovarian endometriotic stromal cells in vitro by up-regulating PEDF expression and down-regulating vascular endothelial growth factor (VEGF expression. Moreover, apoptotic index was significantly increased in endometriotic lesions in vivo and endometriotic stromal cells in vitro when treated with PEDF. In mice treated with PEDF, decreased microvessel density labeled by Von Willebrand factor but not by α-Smooth Muscle Actin was observed in endometriotic lesions. And it showed no increase in PEDF expression of the ovary and uterus tissues. These findings suggest that PEDF gene therapy may be a new treatment for endometriosis.

  1. Zinc deficiency leads to lipofuscin accumulation in the retinal pigment epithelium of pigmented rats.

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    Sylvie Julien

    Full Text Available BACKGROUND: Age-related macular degeneration (AMD is associated with lipofuscin accumulation whereas the content of melanosomes decreases. Melanosomes are the main storage of zinc in the pigmented tissues. Since the elderly population, as the most affected group for AMD, is prone to zinc deficit, we investigated the chemical and ultrastructural effects of zinc deficiency in pigmented rat eyes after a six-month zinc penury diet. METHODOLOGY/PRINCIPAL FINDINGS: Adult Long Evans (LE rats were investigated. The control animals were fed with a normal alimentation whereas the zinc-deficiency rats (ZD-LE were fed with a zinc deficient diet for six months. Quantitative Energy Dispersive X-ray (EDX microanalysis yielded the zinc mole fractions of melanosomes in the retinal pigment epithelium (RPE. The lateral resolution of the analysis was 100 nm. The zinc mole fractions of melanosomes were significantly smaller in the RPE of ZD-LE rats as compared to the LE control rats. Light, fluorescence and electron microscopy, as well as immunohistochemistry were performed. The numbers of lipofuscin granules in the RPE and of infiltrated cells (Ø>3 µm found in the choroid were quantified. The number of lipofuscin granules significantly increased in ZD-LE as compared to control rats. Infiltrated cells bigger than 3 µm were only detected in the choroid of ZD-LE animals. Moreover, the thickness of the Bruch's membrane of ZD-LE rats varied between 0.4-3 µm and thin, rangy ED1 positive macrophages were found attached at these sites of Bruch's membrane or even inside it. CONCLUSIONS/SIGNIFICANCE: In pigmented rats, zinc deficiency yielded an accumulation of lipofuscin in the RPE and of large pigmented macrophages in the choroids as well as the appearance of thin, rangy macrophages at Bruch's membrane. Moreover, we showed that a zinc diet reduced the zinc mole fraction of melanosomes in the RPE and modulated the thickness of the Bruch's membrane.

  2. Neurotrophic Effect of Adipose Tissue-Derived Stem Cells on Erectile Function Recovery by Pigment Epithelium-Derived Factor Secretion in a Rat Model of Cavernous Nerve Injury

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    Xin Chen

    2016-01-01

    Full Text Available The paracrine effect is the major mechanism of stem cell therapy. However, the details of the effect’s mechanism remain unknown. The aim of this study is to investigate whether adipose tissue-derived stem cells (ADSCs can ameliorate cavernous nerve injury-induced erectile dysfunction (CNIED rats and to determine its mechanism. Twenty-eight days after intracavernous injection of 5-ethynyl-2-deoxyuridine- (EdU- labeled ADSCs, the erectile function of all the rats was evaluated by intracavernosal pressure (ICP. The ADSCs steadily secreted detectable pigment epithelium-derived factor (PEDF in vitro. The expression of PEDF increased in the penis of the bilateral cavernous nerve injury (BCNI group for 14 days and then gradually decreased. On day 28 after the intracavernous injection, the ADSCs group exhibited a significantly increased ICP compared with the phosphate buffered saline- (PBS- treated group. Moreover, the neuronal nitric oxide synthase (nNOS and S100 expression in penile dorsal nerves and the smooth muscle content to collagen ratio in penile tissues significantly increased. Furthermore, elevated PEDF, p-Akt, and p-eNOS were identified in the ADSCs group. This study demonstrated that intracavernous injection of ADSCs improved erectile function, repaired the nerve, and corrected penile fibrosis. One potential mechanism is the PEDF secretion of ADSCs and subsequent PI3K/Akt pathway activation.

  3. Activation of muscarinic acetylcholine receptors elicits pigment granule dispersion in retinal pigment epithelium isolated from bluegill

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    González, Alfredo; Crittenden, Elizabeth L; García, Dana M

    2004-01-01

    Background In fish, melanin pigment granules in the retinal pigment epithelium disperse into apical projections as part of the suite of responses the eye makes to bright light conditions. This pigment granule dispersion serves to reduce photobleaching and occurs in response to neurochemicals secreted by the retina. Previous work has shown that acetylcholine may be involved in inducing light-adaptive pigment dispersion. Acetylcholine receptors are of two main types, nicotinic and muscarinic. Muscarinic receptors are in the G-protein coupled receptor superfamily, and five different muscarinic receptors have been molecularly cloned in human. These receptors are coupled to adenylyl cyclase, calcium mobilization and ion channel activation. To determine the receptor pathway involved in eliciting pigment granule migration, we isolated retinal pigment epithelium from bluegill and subjected it to a battery of cholinergic agents. Results The general cholinergic agonist carbachol induces pigment granule dispersion in isolated retinal pigment epithelium. Carbachol-induced pigment granule dispersion is blocked by the muscarinic antagonist atropine, by the M1 antagonist pirenzepine, and by the M3 antagonist 4-DAMP. Pigment granule dispersion was also induced by the M1 agonist 4-[N-(4-chlorophenyl) carbamoyloxy]-4-pent-2-ammonium iodide. In contrast the M2 antagonist AF-DX 116 and the M4 antagonist tropicamide failed to block carbachol-induced dispersion, and the M2 agonist arecaidine but-2-ynyl ester tosylate failed to elicit dispersion. Conclusions Our results suggest that carbachol-mediated pigment granule dispersion occurs through the activation of Modd muscarinic receptors, which in other systems couple to phosphoinositide hydrolysis and elevation of intracellular calcium. This conclusion must be corroborated by molecular studies, but suggests Ca2+-dependent pathways may be involved in light-adaptive pigment dispersion. PMID:15251036

  4. Activation of muscarinic acetylcholine receptors elicits pigment granule dispersion in retinal pigment epithelium isolated from bluegill

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    Crittenden Elizabeth L

    2004-07-01

    Full Text Available Abstract Background In fish, melanin pigment granules in the retinal pigment epithelium disperse into apical projections as part of the suite of responses the eye makes to bright light conditions. This pigment granule dispersion serves to reduce photobleaching and occurs in response to neurochemicals secreted by the retina. Previous work has shown that acetylcholine may be involved in inducing light-adaptive pigment dispersion. Acetylcholine receptors are of two main types, nicotinic and muscarinic. Muscarinic receptors are in the G-protein coupled receptor superfamily, and five different muscarinic receptors have been molecularly cloned in human. These receptors are coupled to adenylyl cyclase, calcium mobilization and ion channel activation. To determine the receptor pathway involved in eliciting pigment granule migration, we isolated retinal pigment epithelium from bluegill and subjected it to a battery of cholinergic agents. Results The general cholinergic agonist carbachol induces pigment granule dispersion in isolated retinal pigment epithelium. Carbachol-induced pigment granule dispersion is blocked by the muscarinic antagonist atropine, by the M1 antagonist pirenzepine, and by the M3 antagonist 4-DAMP. Pigment granule dispersion was also induced by the M1 agonist 4-[N-(4-chlorophenyl carbamoyloxy]-4-pent-2-ammonium iodide. In contrast the M2 antagonist AF-DX 116 and the M4 antagonist tropicamide failed to block carbachol-induced dispersion, and the M2 agonist arecaidine but-2-ynyl ester tosylate failed to elicit dispersion. Conclusions Our results suggest that carbachol-mediated pigment granule dispersion occurs through the activation of Modd muscarinic receptors, which in other systems couple to phosphoinositide hydrolysis and elevation of intracellular calcium. This conclusion must be corroborated by molecular studies, but suggests Ca2+-dependent pathways may be involved in light-adaptive pigment dispersion.

  5. Blockade of Jagged/Notch pathway abrogates transforming growth factor β2-induced epithelial-mesenchymal transition in human retinal pigment epithelium cells.

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    Chen, X; Xiao, W; Liu, X; Zeng, M; Luo, L; Wu, M; Ye, S; Liu, Y

    2014-05-01

    The epithelial-mesenchymal transition (EMT) of retinal pigment epithelium (RPE) cells plays a key role in proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR), which lead to the loss of vision. The Jagged/Notch pathway has been reported to be essential in EMT during embryonic development, fibrotic diseases and cancer metastasis. However, the function of Jagged/Notch signaling in EMT of RPE cells is unknown. Thus, we hypothesized that a crosstalk between Notch and transforming growth factor β2 (TGF-β2) signaling could induce EMT in RPE cells, which subsequently contributes to PVR and PDR. Here, we demonstrate that Jagged-1/Notch pathway is involved in the TGF-β2-mediated EMT of human RPE cells. Blockade of Notch pathway with DAPT (a specific inhibitor of Notch receptor cleavage) and knockdown of Jagged-1 expression inhibited TGF-β2-induced EMT through regulating the expression of Snail, Slug and ZEB1. Besides the canonical Smad signaling pathway, the noncanonical PI3K/Akt and MAPK pathway also contributed to TGF-β2-induced up-regulation of Jagged-1 in RPE cells. Overexpression of Jagged-1 could mimic TGF-β2 induce EMT. Our data suggest that the Jagged-1/Notch signaling pathway plays a critical role in TGF-β2-induced EMT in human RPE cells, and may contribute to the development of PVR and PDR. Inhibition of the Jagged/Notch signaling pathway, therefore, may have therapeutic value in the prevention and treatment of PVR and PDR.

  6. X-box binding protein 1 is essential for the anti-oxidant defense and cell survival in the retinal pigment epithelium.

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    Yimin Zhong

    Full Text Available Damage to the retinal pigment epithelium (RPE is an early event in the pathogenesis of age-related macular degeneration (AMD. X-box binding protein 1 (XBP1 is a key transcription factor that regulates endoplasmic reticulum (ER homeostasis and cell survival. This study aimed to delineate the role of endogenous XBP1 in the RPE. Our results show that in a rat model of light-induced retinal degeneration, XBP1 activation was suppressed in the RPE/choroid complex, accompanied by decreased anti-oxidant genes and increased oxidative stress. Knockdown of XBP1 by siRNA resulted in reduced expression of SOD1, SOD2, catalase, and glutathione synthase and sensitized RPE cells to oxidative damage. Using Cre/LoxP system, we generated a mouse line that lacks XBP1 only in RPE cells. Compared to wildtype littermates, RPE-XBP1 KO mice expressed less SOD1, SOD2, and catalase in the RPE, and had increased oxidative stress. At age 3 months and older, these mice exhibited apoptosis of RPE cells, decreased number of cone photoreceptors, shortened photoreceptor outer segment, reduced ONL thickness, and deficit in retinal function. Electron microscopy showed abnormal ultrastructure, Bruch's membrane thickening, and disrupted basal membrane infolding in XBP1-deficient RPE. These results indicate that XBP1 is an important gene involved in regulation of the anti-oxidant defense in the RPE, and that impaired activation of XBP1 may contribute to RPE dysfunction and cell death during retinal degeneration and AMD.

  7. Myeloid cells expressing VEGF and arginase-1 following uptake of damaged retinal pigment epithelium suggests potential mechanism that drives the onset of choroidal angiogenesis in mice.

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    Jian Liu

    Full Text Available Whilst data recognise both myeloid cell accumulation during choroidal neovascularisation (CNV as well as complement activation, none of the data has presented a clear explanation for the angiogenic drive that promotes pathological angiogenesis. One possibility that is a pre-eminent drive is a specific and early conditioning and activation of the myeloid cell infiltrate. Using a laser-induced CNV murine model, we have identified that disruption of retinal pigment epithelium (RPE and Bruch's membrane resulted in an early recruitment of macrophages derived from monocytes and microglia, prior to angiogenesis and contemporaneous with lesional complement activation. Early recruited CD11b(+ cells expressed a definitive gene signature of selective inflammatory mediators particularly a pronounced Arg-1 expression. Accumulating macrophages from retina and peripheral blood were activated at the site of injury, displaying enhanced VEGF expression, and notably prior to exaggerated VEGF expression from RPE, or earliest stages of angiogenesis. All of these initial events, including distinct VEGF (+ Arg-1(+ myeloid cells, subsided when CNV was established and at the time RPE-VEGF expression was maximal. Depletion of inflammatory CCR2-positive monocytes confirmed origin of infiltrating monocyte Arg-1 expression, as following depletion Arg-1 signal was lost and CNV suppressed. Furthermore, our in vitro data supported a myeloid cell uptake of damaged RPE or its derivatives as a mechanism generating VEGF (+ Arg-1(+ phenotype in vivo. Our results reveal a potential early driver initiating angiogenesis via myeloid-derived VEGF drive following uptake of damaged RPE and deliver an explanation of why CNV develops during any of the stages of macular degeneration and can be explored further for therapeutic gain.

  8. Optical modulation of transgene expression in retinal pigment epithelium

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    Palanker, D.; Lavinsky, D.; Chalberg, T.; Mandel, Y.; Huie, P.; Dalal, R.; Marmor, M.

    2013-03-01

    Over a million people in US alone are visually impaired due to the neovascular form of age-related macular degeneration (AMD). The current treatment is monthly intravitreal injections of a protein which inhibits Vascular Endothelial Growth Factor, thereby slowing progression of the disease. The immense financial and logistical burden of millions of intravitreal injections signifies an urgent need to develop more long-lasting and cost-effective treatments for this and other retinal diseases. Viral transfection of ocular cells allows creation of a "biofactory" that secretes therapeutic proteins. This technique has been proven successful in non-human primates, and is now being evaluated in clinical trials for wet AMD. However, there is a critical need to down-regulate gene expression in the case of total resolution of retinal condition, or if patient has adverse reaction to the trans-gene products. The site for genetic therapy of AMD and many other retinal diseases is the retinal pigment epithelium (RPE). We developed and tested in pigmented rabbits, an optical method to down-regulate transgene expression in RPE following vector delivery, without retinal damage. Microsecond exposures produced by a rapidly scanning laser vaporize melanosomes and destroy a predetermined fraction of the RPE cells selectively. RPE continuity is restored within days by migration and proliferation of adjacent RPE, but since the transgene is not integrated into the nucleus it is not replicated. Thus, the decrease in transgene expression can be precisely determined by the laser pattern density and further reduced by repeated treatment without affecting retinal structure and function.

  9. Tumorigenicity studies of induced pluripotent stem cell (iPSC-derived retinal pigment epithelium (RPE for the treatment of age-related macular degeneration.

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    Hoshimi Kanemura

    Full Text Available Basic studies of human pluripotential stem cells have advanced rapidly and stem cell products are now seeing therapeutic applications. However, questions remain regarding the tumorigenic potential of such cells. Here, we report the tumorigenic potential of induced pluripotent stem cell (iPSC-derived retinal pigment epithelium (RPE for the treatment of wet-type, age-related macular degeneration (AMD. First, immunodeficient mouse strains (nude, SCID, NOD-SCID and NOG were tested for HeLa cells' tumor-forming capacity by transplanting various cell doses subcutaneously with or without Matrigel. The 50% Tumor Producing Dose (TPD50 value is the minimal dose of transplanted cells that generated tumors in 50% of animals. For HeLa cells, the TPD50 was the lowest when cells were embedded in Matrigel and transplanted into NOG mice (TPD50 = 10(1.1, n = 75. The TPD50 for undifferentiated iPSCs transplanted subcutaneously to NOG mice in Matrigel was 10(2.12; (n = 30. Based on these experiments, 1×10(6 iPSC-derived RPE were transplanted subcutaneously with Matrigel, and no tumor was found during 15 months of monitoring (n = 65. Next, to model clinical application, we assessed the tumor-forming potential of HeLa cells and iPSC 201B7 cells following subretinal transplantation of nude rats. The TPD50 for iPSCs was 10(4.73 (n = 20 and for HeLa cells 10(1.32 (n = 37 respectively. Next, the tumorigenicity of iPSC-derived RPE was tested in the subretinal space of nude rats by transplanting 0.8-1.5×10(4 iPSC-derived RPE in a collagen-lined (1 mm×1 mm sheet. No tumor was found with iPSC-derived RPE sheets during 6-12 months of monitoring (n = 26. Considering the number of rodents used, the monitoring period, the sensitivity of detecting tumors via subcutaneous and subretinal administration routes and the incidence of tumor formation from the iPSC-derived RPE, we conclude that the tumorigenic potential of the iPSC-derived RPE was

  10. Retina-specific nuclear receptor: A potential regulator of cellular retinaldehyde-binding protein expressed in retinal pigment epithelium and Müller glial cells.

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    Chen, F; Figueroa, D J; Marmorstein, A D; Zhang, Q; Petrukhin, K; Caskey, C T; Austin, C P

    1999-12-21

    In an effort to identify nuclear receptors important in retinal disease, we screened a retina cDNA library for nuclear receptors. Here we describe the identification of a retina-specific nuclear receptor (RNR) from both human and mouse. Human RNR is a splice variant of the recently published photoreceptor cell-specific nuclear receptor [Kobayashi, M., Takezawa, S., Hara, K., Yu, R. T., Umesono, Y., Agata, K., Taniwaki, M., Yasuda, K. & Umesono, K. (1999) Proc. Natl. Acad. Sci. USA 96, 4814-4819] whereas the mouse RNR is a mouse ortholog. Northern blot and reverse transcription-PCR analyses of human mRNA samples demonstrate that RNR is expressed exclusively in the retina, with transcripts of approximately 7.5 kb, approximately 3.0 kb, and approximately 2.3 kb by Northern blot analysis. In situ hybridization with multiple probes on both primate and mouse eye sections demonstrates that RNR is expressed in the retinal pigment epithelium and in Müller glial cells. By using the Gal4 chimeric receptor/reporter cotransfection system, the ligand binding domain of RNR was found to repress transcriptional activity in the absence of exogenous ligand. Gel mobility shift assays revealed that RNR can interact with the promoter of the cellular retinaldehyde binding protein gene in the presence of retinoic acid receptor (RAR) and/or retinoid X receptor (RXR). These data raise the possibility that RNR acts to regulate the visual cycle through its interaction with cellular retinaldehyde binding protein and therefore may be a target for retinal diseases such as retinitis pigmentosa and age-related macular degeneration.

  11. Infection of Human Retinal Pigment Epithelium with Chlamydia trachomatis.

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    Ernest Boiko

    Full Text Available Little is known about the susceptibility of posterior segment tissues, particularly the human retinal pigment epithelium (hRPE, to Chlamydia trachomatis. The purpose of the study was to investigate the possibility of infecting the hRPE with Chlamydia trachomatis, and to examine the infectivity of different Chlamydia trachomatis clinical isolates for hRPE cells and the hRPE cell response to the infection.Cultured hRPE and McCoy cells were inoculated with eight Chlamydia trachomatis (serovar E clinical isolates at multiplicity of infection (MOI of 2.0 or 0.3. To detect Chlamydia trachomatis, samples were stained immunohistochemically with anti-major outer membrane protein antibodies at 24h, 48h, and 72h postinoculation (PI. The changes in the expression of signaling molecules and proteins of cytoskeleton and extracellular matrix in hRPE cells were examined immunohistochemically.All eight clinical isolates demonstrated ability to infect hRPE cells. At equal MOI of 0.3, the infectivity of Chlamydia trachomatis clinical isolates for RPE culture was found to be at least as high as that for McCoy cell culture. At 24h PI, the percentage of inclusion-containing cells varied from 1.5 ± 0.52 to 14.6 ± 3.3% in hRPE cell culture infected at MOI of 2.0 against 0.37 ± 0.34 to 8.9 ± 0.2% in McCoy cell culture infected at MOI of 0.3. Collagen type I, collagen type IV, basic fibroblast growth factor, transforming growth factor-beta and interleukin-8 expression at 48h PI were maximally increased, by 2.1-, 1.3-, 1.5-, 1.5- and 1.6-fold, respectively, in the Chlamydia trachomatis-infected compared with control hRPE cell culture specimens (P < 0.05.This study, for the first time, proved the possibility of infecting hRPE cultured cells with Chlamydia trachomatis, which leads to proproliferative and proinflammatory changes in the expression of signaling molecules and extracellular matrix components.

  12. [Macroadenoma of the non-pigmented ciliary epithelium].

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    Lara-Medina, J; Ispa Callén, C; González del Valle, F; Mate Valdezate, A

    2014-06-01

    We report the clinical features and surgery of a patient with an adenoma of the non-pigmented ciliary epithelium. The adenoma measured 5 × 7 mm. The patient underwent radical ocular surgery consisting of partial iridocyclectomy associated to lamellar sclerouvectomy. Adenomas of ciliary body can mimic clinically amelanotic melanomas. We present details of the patient's medical records and review the literature. Clinically, adenoma in ciliary body can mimic amelanotic melanomas. Conservative surgery of the eye allows diagnosis and treatment, maintaining visual function. Copyright © 2010 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  13. Functional annotation of the human retinal pigment epithelium transcriptome

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    Gorgels Theo GMF

    2009-04-01

    Full Text Available Abstract Background To determine level, variability and functional annotation of gene expression of the human retinal pigment epithelium (RPE, the key tissue involved in retinal diseases like age-related macular degeneration and retinitis pigmentosa. Macular RPE cells from six selected healthy human donor eyes (aged 63–78 years were laser dissected and used for 22k microarray studies (Agilent technologies. Data were analyzed with Rosetta Resolver, the web tool DAVID and Ingenuity software. Results In total, we identified 19,746 array entries with significant expression in the RPE. Gene expression was analyzed according to expression levels, interindividual variability and functionality. A group of highly (n = 2,194 expressed RPE genes showed an overrepresentation of genes of the oxidative phosphorylation, ATP synthesis and ribosome pathways. In the group of moderately expressed genes (n = 8,776 genes of the phosphatidylinositol signaling system and aminosugars metabolism were overrepresented. As expected, the top 10 percent (n = 2,194 of genes with the highest interindividual differences in expression showed functional overrepresentation of the complement cascade, essential in inflammation in age-related macular degeneration, and other signaling pathways. Surprisingly, this same category also includes the genes involved in Bruch's membrane (BM composition. Among the top 10 percent of genes with low interindividual differences, there was an overrepresentation of genes involved in local glycosaminoglycan turnover. Conclusion Our study expands current knowledge of the RPE transcriptome by assigning new genes, and adding data about expression level and interindividual variation. Functional annotation suggests that the RPE has high levels of protein synthesis, strong energy demands, and is exposed to high levels of oxidative stress and a variable degree of inflammation. Our data sheds new light on the molecular composition of BM, adjacent to the

  14. Gene expression analysis of zebrafish melanocytes, iridophores, and retinal pigmented epithelium reveals indicators of biological function and developmental origin.

    Science.gov (United States)

    Higdon, Charles W; Mitra, Robi D; Johnson, Stephen L

    2013-01-01

    In order to facilitate understanding of pigment cell biology, we developed a method to concomitantly purify melanocytes, iridophores, and retinal pigmented epithelium from zebrafish, and analyzed their transcriptomes. Comparing expression data from these cell types and whole embryos allowed us to reveal gene expression co-enrichment in melanocytes and retinal pigmented epithelium, as well as in melanocytes and iridophores. We found 214 genes co-enriched in melanocytes and retinal pigmented epithelium, indicating the shared functions of melanin-producing cells. We found 62 genes significantly co-enriched in melanocytes and iridophores, illustrative of their shared developmental origins from the neural crest. This is also the first analysis of the iridophore transcriptome. Gene expression analysis for iridophores revealed extensive enrichment of specific enzymes to coordinate production of their guanine-based reflective pigment. We speculate the coordinated upregulation of specific enzymes from several metabolic pathways recycles the rate-limiting substrate for purine synthesis, phosphoribosyl pyrophosphate, thus constituting a guanine cycle. The purification procedure and expression analysis described here, along with the accompanying transcriptome-wide expression data, provide the first mRNA sequencing data for multiple purified zebrafish pigment cell types, and will be a useful resource for further studies of pigment cell biology.

  15. Gene expression analysis of zebrafish melanocytes, iridophores, and retinal pigmented epithelium reveals indicators of biological function and developmental origin.

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    Charles W Higdon

    Full Text Available In order to facilitate understanding of pigment cell biology, we developed a method to concomitantly purify melanocytes, iridophores, and retinal pigmented epithelium from zebrafish, and analyzed their transcriptomes. Comparing expression data from these cell types and whole embryos allowed us to reveal gene expression co-enrichment in melanocytes and retinal pigmented epithelium, as well as in melanocytes and iridophores. We found 214 genes co-enriched in melanocytes and retinal pigmented epithelium, indicating the shared functions of melanin-producing cells. We found 62 genes significantly co-enriched in melanocytes and iridophores, illustrative of their shared developmental origins from the neural crest. This is also the first analysis of the iridophore transcriptome. Gene expression analysis for iridophores revealed extensive enrichment of specific enzymes to coordinate production of their guanine-based reflective pigment. We speculate the coordinated upregulation of specific enzymes from several metabolic pathways recycles the rate-limiting substrate for purine synthesis, phosphoribosyl pyrophosphate, thus constituting a guanine cycle. The purification procedure and expression analysis described here, along with the accompanying transcriptome-wide expression data, provide the first mRNA sequencing data for multiple purified zebrafish pigment cell types, and will be a useful resource for further studies of pigment cell biology.

  16. Epithelium

    Science.gov (United States)

    The term "epithelium" refers to layers of cells that line hollow organs and glands. It is also those cells that make ... Epithelium. In: Kierszenbaum AL, Tres LL. Histology and Cell Biology - An Introduction to Pathology , 3rd ed. Philadelphia, ...

  17. Structure and function of the retinal pigment epithelium, photoreceptors and cornea in the eye of Sardinella aurita (Clupeidae, Teleostei

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    Mostafa Ali Salem

    2016-05-01

    Full Text Available The structure of the pigment epithelium, photoreceptors and the cornea in the eye of a teleost, Sardinella aurita was examined by light and electron microscopy. The retinal pigment epithelium forms a single layer of cells joined laterally by cell junctions. Centrally in the retina these cells are columnar, while more peripherally they become cuboidal in shape. The basal (scleral border of the pigment epithelial cells is not infolded but is relatively smooth. Phagosomes containing lysosome-like bodies are also common features of the retinal pigment epithelium. Numerous melanosomes (pigment granules are abundant throughout the epithelial cells. These melanosomes probably absorb light which has passed through the photoreceptor layer. Four photoreceptor cells were identified; rods, long single cones, short single cones and double cones. The presence of these types suggests a diversity of photoreceptor function. Square mosaic pattern of cones and well-developed choroid gland are also main features of the eye. The inner segment of rods and cones were rich in organelles indicating much synthetic activity. Calycal processes projecting from cone outer segments are also observed. The cornea includes an epithelium with a complex pattern of surface microplicae, a basement membrane, dermal stroma, an iridescent layer, scleral stroma, Descemet’s membrane and endothelium. The autochthonous layer which is seen in some teleosts has not been observed in the cornea of this species. These and other observations were discussed in relation to the photic environment and habits of this fish.

  18. A regulatory loop involving PAX6, MITF, and WNT signaling controls retinal pigment epithelium development.

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    Kapil Bharti

    2012-07-01

    Full Text Available The separation of the optic neuroepithelium into future retina and retinal pigment epithelium (RPE is a critical event in early eye development in vertebrates. Here we show in mice that the transcription factor PAX6, well-known for its retina-promoting activity, also plays a crucial role in early pigment epithelium development. This role is seen, however, only in a background genetically sensitized by mutations in the pigment cell transcription factor MITF. In fact, a reduction in Pax6 gene dose exacerbates the RPE-to-retina transdifferentiation seen in embryos homozygous for an Mitf null allele, and it induces such a transdifferentiation in embryos that are either heterozygous for the Mitf null allele or homozygous for an RPE-specific hypomorphic Mitf allele generated by targeted mutation. Conversely, an increase in Pax6 gene dose interferes with transdifferentiation even in homozygous Mitf null embryos. Gene expression analyses show that, together with MITF or its paralog TFEC, PAX6 suppresses the expression of Fgf15 and Dkk3. Explant culture experiments indicate that a combination of FGF and DKK3 promote retina formation by inhibiting canonical WNT signaling and stimulating the expression of retinogenic genes, including Six6 and Vsx2. Our results demonstrate that in conjunction with Mitf/Tfec Pax6 acts as an anti-retinogenic factor, whereas in conjunction with retinogenic genes it acts as a pro-retinogenic factor. The results suggest that careful manipulation of the Pax6 regulatory circuit may facilitate the generation of retinal and pigment epithelium cells from embryonic or induced pluripotent stem cells.

  19. Lipofuscin and A2E accumulate with age in the retinal pigment epithelium of Nrl-/- mice.

    Science.gov (United States)

    Boyer, Nicholas P; Tang, Peter H; Higbee, Daniel; Ablonczy, Zsolt; Crouch, Rosalie K; Koutalos, Yiannis

    2012-01-01

    Lipofuscin is a fluorescent material with significant phototoxic potential that accumulates with age in the retinal pigment epithelium (RPE) of the eye. It is thought to be a factor in retinal degeneration diseases. The most extensively characterized lipofuscin component, N-retinylidene-N-retinylethanolamine (A2E), has been proposed to be a byproduct of reactions involving the visual pigment chromophore. To examine the impact of the visual pigment and photoreceptor cell type on lipofuscin accumulation, we analyzed the RPE from Nrl(-/-) mice of various ages for lipofuscin fluorescence and A2E levels. The photoreceptor cells of the Nrl(-/-) retina contain only cone-like pigments, and produce cone-like responses to photostimulation. The cone-like nature of these cells was confirmed by the presence of RPE65. Lipofuscin was measured with fluorescence imaging, whereas A2E was quantified by UV/VIS absorbance spectroscopy coupled to HPLC. The identity of A2E was corroborated with tandem mass spectrometry. Lipofuscin and A2E accumulated with age, albeit to lower levels compared with wild type mice. The emission spectra of RPE lipofuscin granules from Nrl(-/-) mice were similar to those from wild type mice, with λ(max) ca 610 nm. These results demonstrate that cone visual pigments can contribute to the production of lipofuscin and A2E. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  20. Translational read-through of the RP2 Arg120stop mutation in patient iPSC-derived retinal pigment epithelium cells

    Science.gov (United States)

    Schwarz, Nele; Carr, Amanda-Jayne; Lane, Amelia; Moeller, Fabian; Chen, Li Li; Aguilà, Mònica; Nommiste, Britta; Muthiah, Manickam N.; Kanuga, Naheed; Wolfrum, Uwe; Nagel-Wolfrum, Kerstin; da Cruz, Lyndon; Coffey, Peter J.; Cheetham, Michael E.; Hardcastle, Alison J.

    2015-01-01

    Mutations in the RP2 gene lead to a severe form of X-linked retinitis pigmentosa. RP2 patients frequently present with nonsense mutations and no treatments are currently available to restore RP2 function. In this study, we reprogrammed fibroblasts from an RP2 patient carrying the nonsense mutation c.519C>T (p.R120X) into induced pluripotent stem cells (iPSC), and differentiated these cells into retinal pigment epithelial cells (RPE) to study the mechanisms of disease and test potential therapies. RP2 protein was undetectable in the RP2 R120X patient cells, suggesting a disease mechanism caused by complete lack of RP2 protein. The RP2 patient fibroblasts and iPSC-derived RPE cells showed phenotypic defects in IFT20 localization, Golgi cohesion and Gβ1 trafficking. These phenotypes were corrected by over-expressing GFP-tagged RP2. Using the translational read-through inducing drugs (TRIDs) G418 and PTC124 (Ataluren), we were able to restore up to 20% of endogenous, full-length RP2 protein in R120X cells. This level of restored RP2 was sufficient to reverse the cellular phenotypic defects observed in both the R120X patient fibroblasts and iPSC-RPE cells. This is the first proof-of-concept study to demonstrate successful read-through and restoration of RP2 function for the R120X nonsense mutation. The ability of the restored RP2 protein level to reverse the observed cellular phenotypes in cells lacking RP2 indicates that translational read-through could be clinically beneficial for patients. PMID:25292197

  1. Methods for culturing retinal pigment epithelial cells: a review of current protocols and future recommendations

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    Aaron H Fronk

    2016-07-01

    Full Text Available The retinal pigment epithelium is an important part of the vertebrate eye, particularly in studying the causes and possible treatment of age-related macular degeneration. The retinal pigment epithelium is difficult to access in vivo due to its location at the back of the eye, making experimentation with age-related macular degeneration treatments problematic. An alternative to in vivo experimentation is cultivating the retinal pigment epithelium in vitro, a practice that has been going on since the 1970s, providing a wide range of retinal pigment epithelial culture protocols, each producing cells and tissue of varying degrees of similarity to natural retinal pigment epithelium. The purpose of this review is to provide researchers with a ready list of retinal pigment epithelial protocols, their effects on cultured tissue, and their specific possible applications. Protocols using human and animal retinal pigment epithelium cells, derived from tissue or cell lines, are discussed, and recommendations for future researchers included.

  2. The retinal pigment epithelium utilizes fatty acids for ketogenesis.

    Science.gov (United States)

    Adijanto, Jeffrey; Du, Jianhai; Moffat, Cynthia; Seifert, Erin L; Hurle, James B; Philp, Nancy J

    2014-07-25

    Every day, shortly after light onset, photoreceptor cells shed approximately a tenth of their outer segment. The adjacent retinal pigment epithelial (RPE) cells phagocytize and digest shed photoreceptor outer segment, which provides a rich source of fatty acids that could be utilized as an energy substrate. From a microarray analysis, we found that RPE cells express particularly high levels of the mitochondrial HMG-CoA synthase 2 (Hmgcs2) compared with all other tissues (except the liver and colon), leading to the hypothesis that RPE cells, like hepatocytes, can produce β-hydroxybutyrate (β-HB) from fatty acids. Using primary human fetal RPE (hfRPE) cells cultured on Transwell filters with separate apical and basal chambers, we demonstrate that hfRPE cells can metabolize palmitate, a saturated fatty acid that constitutes .15% of all lipids in the photoreceptor outer segment, to produce β-HB. Importantly, we found that hfRPE cells preferentially release β-HB into the apical chamber and that this process is mediated primarily by monocarboxylate transporter isoform 1 (MCT1). Using a GC-MS analysis of (13)C-labeled metabolites, we showed that retinal cells can take up and metabolize (13)C-labeled β-HB into various TCA cycle intermediates and amino acids. Collectively, our data support a novel mechanism of RPE-retina metabolic coupling in which RPE cells metabolize fatty acids to produce β-HB, which is transported to the retina for use as a metabolic substrate.

  3. αB crystallin is apically secreted within exosomes by polarized human retinal pigment epithelium and provides neuroprotection to adjacent cells.

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    Parameswaran G Sreekumar

    Full Text Available αB crystallin is a chaperone protein with anti-apoptotic and anti-inflammatory functions and has been identified as a biomarker in age-related macular degeneration. The purpose of this study was to determine whether αB crystallin is secreted from retinal pigment epithelial (RPE cells, the mechanism of this secretory pathway and to determine whether extracellular αB crystallin can be taken up by adjacent retinal cells and provide protection from oxidant stress. We used human RPE cells to establish that αB crystallin is secreted by a non-classical pathway that involves exosomes. Evidence for the release of exosomes by RPE and localization of αB crystallin within the exosomes was achieved by immunoblot, immunofluorescence, and electron microscopic analyses. Inhibition of lipid rafts or exosomes significantly reduced αB crystallin secretion, while inhibitors of classic secretory pathways had no effect. In highly polarized RPE monolayers, αB crystallin was selectively secreted towards the apical, photoreceptor-facing side. In support, confocal microscopy established that αB crystallin was localized predominantly in the apical compartment of RPE monolayers, where it co-localized in part with exosomal marker CD63. Severe oxidative stress resulted in barrier breakdown and release of αB crystallin to the basolateral side. In normal mouse retinal sections, αB crystallin was identified in the interphotoreceptor matrix. An increased uptake of exogenous αB crystallin and protection from apoptosis by inhibition of caspase 3 and PARP activation were observed in stressed RPE cultures. αB Crystallin was taken up by photoreceptors in mouse retinal explants exposed to oxidative stress. These results demonstrate an important role for αB crystallin in maintaining and facilitating a neuroprotective outer retinal environment and may also explain the accumulation of αB crystallin in extracellular sub-RPE deposits in the stressed microenvironment in age

  4. Pigment epithelium-derived factor mediates impaired lung vascular development in neonatal hyperoxia.

    Science.gov (United States)

    Chetty, Anne; Bennett, Michelle; Dang, Linh; Nakamura, Daisy; Cao, Gong-Jie; Mujahid, Sana; Volpe, MaryAnn; Herman, Ira; Becerra, S Patricia; Nielsen, Heber C

    2015-03-01

    Bronchopulmonary dysplasia is a chronic lung disease of preterm infants characterized by arrested microvascularization and alveolarization. Studies show the importance of proangiogenic factors for alveolarization, but the importance of antiangiogenic factors is unknown. We proposed that hyperoxia increases the potent angiostatin, pigment epithelium-derived factor (PEDF), in neonatal lungs, inhibiting alveolarization and microvascularization. Wild-type (WT) and PEDF(-/-) mice were exposed to room air (RA) or 0.9 fraction of inspired oxygen from Postnatal Day 5 to 13. PEDF protein was increased in hyperoxic lungs compared with RA-exposed lungs (P epithelium. Hyperoxia reduced alveolarization in WT mice (P lung microvascularization by vascular endothelial growth factor and PEDF was studied in vitro using MFLM-91U cells, a fetal mouse lung endothelial cell line. Vascular endothelial growth factor stimulation of proliferation, migration, and capillary tube formation was inhibited by PEDF. MFLM-91U cells exposed to conditioned medium (CM) from E17 fetal mouse lung type II (T2) cells cultured in 0.9 fraction of inspired oxygen formed fewer capillary tubes than CM from T2 cells cultured in RA (hyperoxia CM, 51 ± 10% of RA CM, P < 0.05), an effect abolished by PEDF antibody. We conclude that PEDF mediates reduced vasculogenesis and alveolarization in neonatal hyperoxia. Bronchopulmonary dysplasia likely results from an altered balance between pro- and antiangiogenic factors.

  5. Controlled exosome release from the retinal pigment epithelium in situ.

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    Locke, Christina J; Congrove, Nicole R; Dismuke, W Michael; Bowen, Trent J; Stamer, W Daniel; McKay, Brian S

    2014-12-01

    Retinal Pigment Epithelial cells (RPE) express both GPR143 and myocilin, which interact in a signal transduction-dependent manner. In heterologous systems, activation of GPR143 with ligand causes transient recruitment of myocilin to internalized receptors, which appears to be the entry point of myocilin to the endocytic pathway. In some but not all cells, myocilin also traffics through the multivesicular body (MVB) and is released on the surface of exosomes in a signal transduction-dependent fashion. Little is known regarding the role of exosomes in RPE, but they likely serve as a mode of communication between the RPE and the outer retina. In this study, we used posterior poles with retina removed from fresh human donor eyes as a model to test the relationship between GPR143, myocilin, and exosomes in an endogenous system. We isolated exosomes released by RPE using differential centrifugation of media conditioned by the RPE for 25 min, and then characterized the exosomes using nanoparticle tracking to determine the number and size of the exosomes. Next, we tested whether ligand stimulation of GPR143 using l-DOPA altered RPE exosome release. Finally, we investigated whether myocilin was present on the exosomes released by RPE and whether l-DOPA stimulation of GPR143 caused recruitment of myocilin to the endocytic pathway, as we have previously observed using cultured cells. Activation of GPR143 halted RPE exosome release, while simultaneously recruiting myocilin to the endocytic compartment. Together, our results indicate that GPR143 and myocilin function in a signal transduction system that can control exosome release from RPE.

  6. Surgical treatment in combined hamartoma of the retina and retinal pigment epithelium.

    Science.gov (United States)

    Sánchez-Vicente, J L; Rueda-Rueda, T; Llerena-Manzorro, L; Molina-Socola, F E; Contreras-Díaz, M; Szewc, M; Vital-Berral, C; Alfaro-Juárez, A; Medina-Tapia, A; López-Herrero, F; González-García, L; Muñoz-Morales, A

    2017-03-01

    The case is presented of a 39 year-old man with a combined hamartoma of the retina and retinal pigment epithelium, who experienced progressive visual loss and worsening of metamorphopsia. The patient underwent vitrectomy and epiretinal component peeling, with improvement in visual acuity, metamorphopsia, and retinal architecture, assessed by optical coherence tomography. Selected patients with combined hamartomas of the retina and retinal pigment epithelium may benefit from surgical management. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Conditional ablation of the choroideremia gene causes age-related changes in mouse retinal pigment epithelium.

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    Silène T Wavre-Shapton

    Full Text Available The retinal pigment epithelium (RPE is a pigmented monolayer of cells lying between the photoreceptors and a layer of fenestrated capillaries, the choriocapillaris. Choroideremia (CHM is an X-linked progressive degeneration of these three layers caused by the loss of function of Rab Escort protein-1 (REP1. REP1 is involved in the prenylation of Rab proteins, key regulators of membrane trafficking. To study the pathological consequences of chronic disruption of membrane traffic in the RPE we used a cell type-specific knock-out mouse model of the disease, where the Chm/Rep1 gene is deleted only in pigmented cells (Chm(Flox, Tyr-Cre+. Transmission electron microscopy (TEM was used to quantitate the melanosome distribution in the RPE and immunofluorescent staining of rhodopsin was used to quantitate phagocytosed rod outer segments in retinal sections. The ultrastructure of the RPE and Bruch's membrane at different ages was characterised by TEM to analyse age-related changes occurring as a result of defects in membrane traffic pathways. Chm/Rep1 gene knockout in RPE cells resulted in reduced numbers of melanosomes in the apical processes and delayed phagosome degradation. In addition, the RPE accumulated pathological changes at 5-6 months of age similar to those observed in 2-year old controls. These included the intracellular accumulation of lipofuscin-containing deposits, disorganised basal infoldings and the extracellular accumulation of basal laminar and basal linear deposits. The phenotype of the Chm(Flox, Tyr-Cre+ mice suggests that loss of the Chm/Rep1 gene causes premature accumulation of features of aging in the RPE. Furthermore, the striking similarities between the present observations and some of the phenotypes reported in age-related macular degeneration (AMD suggest that membrane traffic defects may contribute to the pathogenesis of AMD.

  8. The complex interplay between ERK1/2, TGFβ/Smad, and Jagged/Notch signaling pathways in the regulation of epithelial-mesenchymal transition in retinal pigment epithelium cells.

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    Xiaoyun Chen

    Full Text Available Epithelial-mesenchymal transition (EMT of retinal pigment epithelium (RPE cells is a major pathologic change in the development of proliferative vitreoretinopathy (PVR, which leads to severe visual impairment. ERK1/2 pathway has been reported to play a key role in the carcinogenesis, cancer metastasis, and multiple fibrotic diseases. We hypothesized that ERK1/2 signaling could cross-interact with transforming growth factor β2 (TGFβ2/Smad and Notch signaling pathways in the regulation of EMT in RPE cells. Here, we demonstrated that ERK1/2 signaling was activated in TGFβ2-induced EMT in human RPE cells, while blockade of the canonical TGFβ2/Smad2/3 signaling with SB431542 could not inhibit TGFβ2-induced the activation of ERK1/2. Meanwhile, blockade of ERK1/2 signaling with a specific MEK/ERK1/2 inhibitor U0126 strongly prevented TGFβ2-induced the downregulation of P-cadherin, and the upregulation of α-SMA, collagen type IV, N-cadherin and fibronectin in RPE cells. In addition, we also identified that blockade of ERK1/2 signaling could inhibit not only the canonical TGFβ/Smad signaling, but also the Jagged/Notch pathway. Finally, we found that blockade of Notch pathway with a specific inhibitor DAPT could inhibit TGFβ2-induced the activation of ERK1/2 pathway conversely. Therefore, our study provides evidence that ERK1/2 signaling can cross-interact with the canonical TGFβ/Smad and the Jagged/Notch signaling pathways in RPE cells EMT. ERK1/2 inhibitor may have therapeutic value in the prevention and treatment of PVR and other fibrotic diseases.

  9. Ophthalmoscopy for congenital hypertrophy of the retinal pigment epithelium (CHRPE) in patients with sporadic colorectal carcinoma

    DEFF Research Database (Denmark)

    Hartvigsen, A; Myrhøj, T; Bülow, Steffen

    1995-01-01

    In order to investigate the frequency of congenital hypertrophy of the retinal pigment epithelium (CHRPE) in sporadic colorectal cancer, ophthalmoscopy was carried out in 34 patients with colorectal carcinoma without known familial disposition. CHRPE is one of the most frequent extracolonic...

  10. Ophthalmoscopy for congenital hypertrophy of the retinal pigment epithelium (CHRPE) in patients with sporadic colorectal carcinoma

    DEFF Research Database (Denmark)

    Hartvigsen, A; Myrhøj, T; Bülow, Steffen

    1995-01-01

    In order to investigate the frequency of congenital hypertrophy of the retinal pigment epithelium (CHRPE) in sporadic colorectal cancer, ophthalmoscopy was carried out in 34 patients with colorectal carcinoma without known familial disposition. CHRPE is one of the most frequent extracolonic...

  11. 线粒体DNA损伤与视网膜色素上皮细胞关系的研究进展%The relationship between mitochondrial DNA damage and retinal pigment epithelium cells

    Institute of Scientific and Technical Information of China (English)

    俞永珍; 邹秀兰; 邹玉平

    2015-01-01

    Mitochondrial DNA (mtDNA) is a genetic effect DNA molecule of double closed loop, and is crucial for cells and their functions. Mitochondria take an active part in physiological activities of retinal pigment epithelium (RPE) cells. The oxidative stress is usually occurred in RPE for its active metabolism, which can lead to mitochondria and mtDNA dam⁃age. Once mitochondria and mtDNA lesions have not been repaired timely, the lesions can be accumulated, which can cause dysfunctions and damaged-structures of RPE and mitochondria, and can motivate the progression of cell apoptosis. In the end it can result in some ocular related diseases such as aged-related macular degeneration (AMD). This study reviewed the functional relationship between mtDNA and RPE, and repair and detection methods of mtDNA damage.%线粒体DNA(mtDNA)是线粒体内具有遗传效应的双股闭环DNA分子,对细胞及其功能具有重要作用。视网膜色素上皮(RPE)细胞活动亦由大量线粒体参与。因RPE细胞代谢活跃,当发生氧化应激时可引起线粒体及mtDNA损伤;当线粒体及mtDNA损伤无法及时修复而使损伤积累,可引起RPE及线粒体功能障碍,并诱发启动细胞凋亡,进而引发某些眼病,如年龄相关性黄斑变性等。现就mtDNA与RPE细胞的功能关系、mtDNA损伤修复及检测方法作一综述。

  12. Bis-Retinoid A2E Induces an Increase of Basic Fibroblast Growth Factor via Inhibition of Extracellular Signal-Regulated Kinases 1/2 Pathway in Retinal Pigment Epithelium Cells and Facilitates Phagocytosis

    Science.gov (United States)

    Balmer, Delphine; Bapst-Wicht, Linda; Pyakurel, Aswin; Emery, Martine; Nanchen, Natacha; Bochet, Christian G.; Roduit, Raphael

    2017-01-01

    Age-related macular degeneration (ARMD) is the leading cause of vision loss in developed countries. Hallmarks of the disease are well known; indeed, this pathology is characterized by lipofuscin accumulation, is principally composed of lipid-containing residues of lysosomal digestion. The N-retinyl-N-retinylidene ethanolamine (A2E) retinoid which is thought to be a cytotoxic component for RPE is the best-characterized component of lipofuscin so far. Even if no direct correlation between A2E spatial distribution and lipofuscin fluorescence has been established in aged human RPE, modified forms or metabolites of A2E could be involved in ARMD pathology. Mitogen-activated protein kinase (MAPK) pathways have been involved in many pathologies, but not in ARMD. Therefore, we wanted to analyze the effects of A2E on MAPKs in polarized ARPE19 and isolated mouse RPE cells. We showed that long-term exposure of polarized ARPE19 cells to low A2E dose induces a strong decrease of the extracellular signal-regulated kinases' (ERK1/2) activity. In addition, we showed that A2E, via ERK1/2 decrease, induces a significant decrease of the retinal pigment epithelium-specific protein 65 kDa (RPE65) expression in ARPE19 cells and isolated mouse RPE. In the meantime, we showed that the decrease of ERK1/2 activity mediates an increase of basic fibroblast growth factor (bFGF) mRNA expression and secretion that induces an increase in phagocytosis via a paracrine effect. We suggest that the accumulation of deposits coming from outer segments (OS) could be explained by both an increase of bFGF-induced phagocytosis and by the decrease of clearance by A2E. The bFGF angiogenic protein may therefore be an attractive target to treat ARMD. PMID:28298893

  13. Acetylated bacterial cellulose coated with urinary bladder matrix as a substrate for retinal pigment epithelium.

    Science.gov (United States)

    Gonçalves, Sara; Rodrigues, Inês Patrício; Padrão, Jorge; Silva, João Pedro; Sencadas, Vitor; Lanceros-Mendez, Senentxu; Girão, Henrique; Gama, Francisco M; Dourado, Fernando; Rodrigues, Lígia R

    2016-03-01

    This work evaluated the effect of acetylated bacterial cellulose (ABC) substrates coated with urinary bladder matrix (UBM) on the behavior of retinal pigment epithelium (RPE), as assessed by cell adhesion, proliferation and development of cell polarity exhibiting transepithelial resistance and polygonal shaped-cells with microvilli. Acetylation of bacterial cellulose (BC) generated a moderate hydrophobic surface (around 65°) while the adsorption of UBM onto these acetylated substrates did not affect significantly the surface hydrophobicity. The ABS substrates coated with UBM enabled the development of a cell phenotype closer to that of native RPE cells. These cells were able to express proteins essential for their cytoskeletal organization and metabolic function (ZO-1 and RPE65), while showing a polygonal shaped morphology with microvilli and a monolayer configuration. The coated ABC substrates were also characterized, exhibiting low swelling effect (between 1.5-2.0 swelling/mm(3)), high mechanical strength (2048MPa) and non-pyrogenicity (2.12EU/L). Therefore, the ABC substrates coated with UBM exhibit interesting features as potential cell carriers in RPE transplantation that ought to be further explored.

  14. Effects of white light-emitting diode (LED) exposure on retinal pigment epithelium in vivo.

    Science.gov (United States)

    Jaadane, Imene; Villalpando Rodriguez, Gloria Elisa; Boulenguez, Pierre; Chahory, Sabine; Carré, Samuel; Savoldelli, Michèle; Jonet, Laurent; Behar-Cohen, Francine; Martinsons, Christophe; Torriglia, Alicia

    2017-06-29

    Ageing and alteration of the functions of the retinal pigment epithelium (RPE) are at the origin of lost of vision seen in age-related macular degeneration (AMD). The RPE is known to be vulnerable to high-energy blue light. The white light-emitting diodes (LED) commercially available have relatively high content of blue light, a feature that suggest that they could be deleterious for this retinal cell layer. The aim of our study was to investigate the effects of "white LED" exposure on RPE. For this, commercially available white LEDs were used for exposure experiments on Wistar rats. Immunohistochemical stain on RPE flat mount, transmission electron microscopy and Western blot were used to exam the RPE. LED-induced RPE damage was evaluated by studying oxidative stress, stress response pathways and cell death pathways as well as the integrity of the outer blood-retinal barrier (BRB). We show that white LED light caused structural alterations leading to the disruption of the outer blood-retinal barrier. We observed an increase in oxidized molecules, disturbance of basal autophagy and cell death by necrosis. We conclude that white LEDs induced strong damages in rat RPE characterized by the breakdown of the BRB and the induction of necrotic cell death. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  15. Dynamics and detection of laser induced microbubbles in the retinal pigment epithelium (RPE)

    Science.gov (United States)

    Fritz, Andreas; Ptaszynski, Lars; Stoehr, Hardo; Brinkmann, Ralf

    2007-07-01

    Selective Retina Treatment (SRT) is a new method to treat eye diseases associated with disorders of the RPE. Selective RPE cell damage is achieved by applying a train of 1.7 μs laser pulses at 527 nm. The treatment of retinal diseases as e.g. diabetic maculopathy (DMP), is currently investigated within clinical studies, however 200 ns pulse durations are under investigation. Transient micro bubbles in the retinal pigment epithelium (RPE) are expected to be the origin of cell damage due to irradiation with laser pulses shorter than 50 μs. The bubbles emerge at the strongly absorbing RPE melanosomes. Cell membrane disruption caused by the transient associated volume increase is expected to be the origin of the angiographically observed RPE leakage. We investigate micro bubble formation and dynamics in porcine RPE using pulse durations of 150 ns. A laser interferometry system at 830 nm with the aim of an online dosimetry control for SRT was developed. Bubble formation was detected interferometrically and by fast flash photography. A correlation to cell damage observed with a vitality stain is found. A bubble detection algorithm is presented.

  16. BMP-induced reprogramming of the neural retina into retinal pigment epithelium requires Wnt signalling

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    Jörg Steinfeld

    2017-07-01

    Full Text Available In vertebrates, the retinal pigment epithelium (RPE and photoreceptors of the neural retina (NR comprise a functional unit required for vision. During vertebrate eye development, a conversion of the RPE into NR can be induced by growth factors in vivo at optic cup stages, but the reverse process, the conversion of NR tissue into RPE, has not been reported. Here, we show that bone morphogenetic protein (BMP signalling can reprogram the NR into RPE at optic cup stages in chick. Shortly after BMP application, expression of Microphthalmia-associated transcription factor (Mitf is induced in the NR and selective cell death on the basal side of the NR induces an RPE-like morphology. The newly induced RPE differentiates and expresses Melanosomalmatrix protein 115 (Mmp115 and RPE65. BMP-induced Wnt2b expression is observed in regions of the NR that become pigmented. Loss of function studies show that conversion of the NR into RPE requires both BMP and Wnt signalling. Simultaneous to the appearance of ectopic RPE tissue, BMP application reprogrammed the proximal RPE into multi-layered retinal tissue. The newly induced NR expresses visual segment homeobox-containing gene (Vsx2, and the ganglion and photoreceptor cell markers Brn3α and Visinin are detected. Our results show that high BMP concentrations are required to induce the conversion of NR into RPE, while low BMP concentrations can still induce transdifferentiation of the RPE into NR. This knowledge may contribute to the development of efficient standardized protocols for RPE and NR generation for cell replacement therapies.

  17. Influence of pigment epithelium-derived factor on outcome after striatal cerebral ischemia in the mouse.

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    Marietta Zille

    Full Text Available We here suggest that pigment epithelium-derived factor (PEDF does not have an effect on lesion size, behavioral outcome, cell proliferation, or cell death after striatal ischemia in the mouse. PEDF is a neurotrophic factor with neuroprotective, antiangiogenic, and antipermeability effects. It influences self-renewal of neural stem cells and proliferation of microglia. We investigated whether intraventricular infusion of PEDF reduces infarct size and cell death, ameliorates behavioral outcome, and influences cell proliferation in the one-hour middle cerebral artery occlusion (MCAO mouse model of focal cerebral ischemia. C57Bl6/N mice were implanted with PEDF or artificial cerebrospinal fluid (control osmotic pumps and subjected to 60-minute MCAO 48 hours after pump implantation. They received daily BrdU injections for 7 days after MCAO in order to investigate cell proliferation. Infarct volumes were determined 24 hours after reperfusion using magnetic resonance imaging. We removed the pumps on day 5 and performed behavioral testing between day 7 and 21. Immunohistochemical staining was performed to determine the effect of PEDF on cell proliferation and cell death. Our model produced an ischemic injury confined solely to striatal damage. We detected no reduction in infarct sizes and cell death in PEDF- vs. CSF-infused MCAO mice. Behavioral outcome and cell proliferation did not differ between the groups. However, we cannot exclude that PEDF might work under different conditions in stroke. Further studies will elucidate the effect of PEDF treatment on cell proliferation and behavioral outcome in moderate to severe ischemic injury in the brain.

  18. Bacterial cellulose as a support for the growth of retinal pigment epithelium.

    Science.gov (United States)

    Gonçalves, Sara; Padrão, Jorge; Rodrigues, Inês Patrício; Silva, João Pedro; Sencadas, Vítor; Lanceros-Mendez, Senentxu; Girão, Henrique; Dourado, Fernando; Rodrigues, Lígia R

    2015-04-13

    The feasibility of bacterial cellulose (BC) as a novel substrate for retinal pigment epithelium (RPE) culture was evaluated. Thin (41.6 ± 2.2 μm of average thickness) and heat-dried BC substrates were surface-modified via acetylation and polysaccharide adsorption, using chitosan and carboxymethyl cellulose. All substrates were characterized according to their surface chemistry, wettability, energy, topography, and also regarding their permeability, dimensional stability, mechanical properties, and endotoxin content. Then, their ability to promote RPE cell adhesion and proliferation in vitro was assessed. All surface-modified BC substrates presented similar permeation coefficients with solutes of up to 300 kDa. Acetylation of BC decreased it's swelling and the amount of endotoxins. Surface modification of BC greatly enhanced the adhesion and proliferation of RPE cells. All samples showed similar stress-strain behavior; BC and acetylated BC showed the highest elastic modulus, but the latter exhibited a slightly smaller tensile strength and elongation at break as compared to pristine BC. Although similar proliferation rates were observed among the modified substrates, the acetylated ones showed higher initial cell adhesion. This difference may be mainly due to the moderately hydrophilic surface obtained after acetylation.

  19. Beta cyclodextrins bind, stabilize, and remove lipofuscin bisretinoids from retinal pigment epithelium.

    Science.gov (United States)

    Nociari, Marcelo M; Lehmann, Guillermo L; Perez Bay, Andres E; Radu, Roxana A; Jiang, Zhichun; Goicochea, Shelby; Schreiner, Ryan; Warren, J David; Shan, Jufang; Adam de Beaumais, Ségolène; Ménand, Mickaël; Sollogoub, Matthieu; Maxfield, Frederick R; Rodriguez-Boulan, Enrique

    2014-04-08

    Accumulation of lipofuscin bisretinoids (LBs) in the retinal pigment epithelium (RPE) is the alleged cause of retinal degeneration in genetic blinding diseases (e.g., Stargardt) and a possible etiological agent for age-related macular degeneration. Currently, there are no approved treatments for these diseases; hence, agents that efficiently remove LBs from RPE would be valuable therapeutic candidates. Here, we show that beta cyclodextrins (β-CDs) bind LBs and protect them against oxidation. Computer modeling and biochemical data are consistent with the encapsulation of the retinoid arms of LBs within the hydrophobic cavity of β-CD. Importantly, β-CD treatment reduced by 73% and 48% the LB content of RPE cell cultures and of eyecups obtained from Abca4-Rdh8 double knock-out (DKO) mice, respectively. Furthermore, intravitreal administration of β-CDs reduced significantly the content of bisretinoids in the RPE of DKO animals. Thus, our results demonstrate the effectiveness of β-CDs to complex and remove LB deposits from RPE cells and provide crucial data to develop novel prophylactic approaches for retinal disorders elicited by LBs.

  20. Effects of pigment epithelium derived factor (PEDF) on malignant peripheral nerve sheath tumours (MPNSTs).

    Science.gov (United States)

    Demestre, Maria; Terzi, Menderes Yusuf; Mautner, Victor; Vajkoczy, Peter; Kurtz, Andreas; Piña, Ana Luisa

    2013-12-01

    Neurofibromatosis type 1 (NF1) is an inherited genetic disease affecting 1 in 3,500 individuals. A prominent feature of NF1 is the formation of benign tumours of the peripheral nerve sheath (neurofibromas). However, these can become malignant and form highly metastatic malignant peripheral nerve sheath tumours (MPNST), which are usually fatal despite aggressive surgery, chemotherapy, and radiotherapy. Recent studies have shown that pigment epithelium-derived factor (PEDF) can induce differentiation and inhibit angiogenesis in several kinds of tumours. The present study was designed to determine the in vitro and in vivo effects of PEDF on MPNST angiogenesis and tumour growth. PEDF inhibited proliferation and augmented apoptosis in S462 MPNST cells after 48 h of treatment in culture. In xenografts of S462 MPNST cells in athymic nude mice, PEDF suppressed MPNST tumour burden, due mainly to inhibition of angiogenesis. These results demonstrate for the first time inhibitory effects of PEDF on the growth of human MPNST via induction of anti-angiogenesis and apoptosis. Our results suggest that PEDF could be a novel approach for future therapeutic purposes against MPNST.

  1. Light-Induced Phosphorylation of Crystallins in the Retinal Pigment Epithelium

    Science.gov (United States)

    Lee, Hyunju; Chung, Hyewon; Lee, Sung Haeng; Jahng, Wan Jin

    2017-01-01

    Protein phosphorylations have essential regulatory roles in visual signaling. Previously, we found that phosphorylation of several proteins in the retina and the retinal pigment epithelium (RPE) is involved in anti-apoptotic signaling under oxidative stress conditions, including light exposure. In this study, we used a phosphoprotein enrichment strategy to evaluate the light-induced phosphoproteome of primary bovine RPE cells. Phosphoprotein-enriched extracts from bovine RPE cells exposed to light or dark conditions for 1 hour were separated by 2D SDS-PAGE. Serine and tyrosine phosphorylation were visualized by 2D phospho western blotting and specific phosphorylation sites were analyzed by tandem mass spectrometry. Light induced a marked increase in tyrosine phosphorylation of beta crystallin A3 and A4. The most abundant light-induced up-regulated phosphoproteins were crystallins of 15–25-kDa, including beta crystallin S and zeta crystallin. Phosphorylation of beta crystallin suggests an anti-apoptotic chaperone function in the RPE. Other chaperones, cytoskeletal proteins, and proteins involved in energy balance were expressed at higher levels in the dark. A detailed analysis of RPE phosphoproteins provides a molecular basis for understanding light-induced signal transduction and anti-apoptosis mechanisms. Our data indicates that phosphorylation of crystallins likely represents an important mechanism for RPE shielding from physiological and pathophysiological light-induced oxidative injury. PMID:21094180

  2. Regulation of Autophagy by High Glucose in Human Retinal Pigment Epithelium

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    Jin Yao

    2014-01-01

    Full Text Available Background: Autophagy is a self-degradative process that is important for balancing sources of energy at critical times in development and in response to nutrient stress. Retinal pigment epithelium (RPE works as the outer blood retina barrier and is vulnerable to energy stress-induced injury. However, the effect of high glucose treatment on autophagy is still unclear in RPE. Methods: Transmission electron microscopy was used to detect the generation of autophagosome. Small interfering RNA (siRNA and MTT was used to determine the effect of autophagy on cell viability. Western blots and immunohistochemistry were used to detect the expression pattern of autophagic markers, including LC3 and p62. Results: High glucose treatment results in a significant increase in the generation of autophagosome and altered expression of LC3 and p62. High glucose-induced autophagy is independent of mTOR signaling, but is mainly regulated via ROS-mediated ER stress signaling. Conclusion: In the scenario of high glucose-induced oxidative stress, autophagy may be required for the removal of damaged proteins, and provide a default mechanism to prevent high glucose-induced injury in RPE.

  3. Pigment Epithelium Derived Factor Peptide Protects Murine Hepatocytes from Carbon Tetrachloride-Induced Injury.

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    Shou-Chuan Shih

    Full Text Available Fibrogenesis is induced by repeated injury to the liver and reactive regeneration and leads eventually to liver cirrhosis. Pigment epithelium derived factor (PEDF has been shown to prevent liver fibrosis induced by carbon tetrachloride (CCl4. A 44 amino acid domain of PEDF (44-mer was found to have a protective effect against various insults to several cell types. In this study, we investigated the capability of synthetic 44-mer to protect against liver injury in mice and in primary cultured hepatocytes. Acute liver injury, induced by CCl4, was evident from histological changes, such as cell necrosis, inflammation and apoptosis, and a concomitant reduction of glutathione (GSH and GSH redox enzyme activities in the liver. Intraperitoneal injection of the 44-mer into CCl4-treated mice abolished the induction of AST and ALT and markedly reduced histological signs of liver injury. The 44-mer treatment can reduce hepatic oxidative stress as evident from lower levels of lipid hydroperoxide, and higher levels of GSH. CCl4 caused a reduction of Bcl-xL, PEDF and PPARγ, which was markedly restored by the 44-mer treatment. Consequently, the 44-mer suppressed liver fibrosis induced by repeated CCl4 injury. Furthermore, our observations in primary culture of rat hepatocytes showed that PEDF and the 44-mer protected primary rat hepatocytes against apoptosis induced by serum deprivation and TGF-β1. PEDF/44-mer induced cell protective STAT3 phosphorylation. Pharmacological STAT3 inhibition prevented the antiapoptotic action of PEDF/44-mer. Among several PEDF receptor candidates that may be responsible for hepatocyte protection, we demonstrated that PNPLA2 was essential for PEDF/44-mer-mediated STAT3 phosphorylation and antiapoptotic activity by using siRNA to selectively knockdown PNPLA2. In conclusion, the PEDF 44-mer protects hepatocytes from single and repeated CCl4 injury. This protective effect may stem from strengthening the counter oxidative stress

  4. Activation of Complement by Pigment Epithelium-Derived Factor in Rheumatoid Arthritis

    DEFF Research Database (Denmark)

    Vogt, Leonie M.; Talens, Simone; Kwasniewicz, Ewa

    2017-01-01

    neoepitope in C4d, several molecules that were specifically bound to C4d were identified from pooled synovial fluid (SF) from four rheumatoid arthritis (RA) patients. One of these molecules, pigment epithelium-derived factor (PEDF), is a broadly expressed multifunctional member of the serine proteinase...... inhibitor family. Using ELISA, we confirmed the presence of various amounts of complexes between PEDF and C4d in the SF from 30 RA patients, whereas none were detected in SF from control subjects. Correlation analyses suggested that, in arthritis patients, C4d-PEDF complexes found in sera arise from...

  5. Retinal Pigment Epithelium and Müller Progenitor Cell Interaction Increase Müller Progenitor Cell Expression of PDGFR and Ability to Induce Proliferative Vitreoretinopathy in a Rabbit Model

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    Gisela Velez

    2012-01-01

    Full Text Available Purpose. Proliferative vitreoretinopathy (PVR is a complication of retinal detachment characterized by redetachment of the retina as a result of membrane formation and contraction. A variety of retinal cells, including retinal pigment epithelial (RPE and Müller glia, and growth factors may be responsible. Platelet-derived growth factor receptor alpha (PDGFRα is found in large quantities in PVR membranes, and is intrinsic to the development of PVR in rabbit models. This study explores the expression of PDGFR in cocultures of RPE and Müller cells over time to examine how these two cell types may collaborate in the development of PVR. We also examine how changes in PDGFRα expression alter Müller cell pathogenicity. Methods. Human MIO-M1 Müller progenitor (MPC and ARPE19 cells were studied in a transmembrane coculture system. Immunocytochemistry and Western blot were used to look at PDGFRα, PDGFRβ, and GFAP expression. A transfected MPC line cell line expressing the PDGFRα (MIO-M1α was generated, and tested in a rabbit model for its ability to induce PVR. Results. The expression of PDGFRα and PDGFRβ was upregulated in MIO-M1 MPCs cocultured with ARPE19 cells; GFAP was slightly decreased. Increased expression of PDGFRα in the MIO-M1 cell line resulted in increased pathogenicity and enhanced ability to induce PVR in a rabbit model. Conclusions. Müller and RPE cell interaction can lead to upregulation of PDGFRα and increased Müller cell pathogenicity. Müller cells may play a more active role than previously thought in the development of PVR membranes, particularly when stimulated by an RPE-cell-rich environment. Additional studies of human samples and in animal models are warranted.

  6. Deletion of autophagy inducer RB1CC1 results in degeneration of the retinal pigment epithelium.

    Science.gov (United States)

    Yao, Jingyu; Jia, Lin; Khan, Naheed; Lin, Chengmao; Mitter, Sayak K; Boulton, Michael E; Dunaief, Joshua L; Klionsky, Daniel J; Guan, Jun-Lin; Thompson, Debra A; Zacks, David N

    2015-01-01

    Autophagy regulates cellular homeostasis and response to environmental stress. Within the retinal pigment epithelium (RPE) of the eye, the level of autophagy can change with both age and disease. The purpose of this study is to determine the relationship between reduced autophagy and age-related degeneration of the RPE. The gene encoding RB1CC1/FIP200 (RB1-inducible coiled-coil 1), a protein essential for induction of autophagy, was selectively knocked out in the RPE by crossing Best1-Cre mice with mice in which the Rb1cc1 gene was flanked with Lox-P sites (Rb1cc1(flox/flox)). Ex vivo and in vivo analyses, including western blot, immunohistochemistry, transmission electron microscopy, fundus photography, optical coherence tomography, fluorescein angiography, and electroretinography were performed to assess the structure and function of the retina as a function of age. Deletion of Rb1cc1 resulted in multiple autophagy defects within the RPE including decreased conversion of LC3-I to LC3-II, accumulation of autophagy-targeted precursors, and increased numbers of mitochondria. Age-dependent degeneration of the RPE occurred, with formation of atrophic patches, subretinal migration of activated microglial cells, subRPE deposition of inflammatory and oxidatively damaged proteins, subretinal drusenoid deposits, and occasional foci of choroidal neovascularization. There was secondary loss of photoreceptors overlying the degenerated RPE and reduction in the electroretinogram. These observations are consistent with a critical role of autophagy in the maintenance of normal homeostasis in the aging RPE, and indicate that disruption of autophagy leads to retinal phenotypes associated with age-related degeneration.

  7. Pigment epithelium-derived factor as a multifunctional regulator of wound healing

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    Wietecha, Mateusz S.; Król, Mateusz J.; Michalczyk, Elizabeth R.; Chen, Lin; Gettins, Peter G.

    2015-01-01

    During dermal wound repair, hypoxia-driven proliferation results in dense but highly permeable, disorganized microvascular networks, similar to those in solid tumors. Concurrently, activated dermal fibroblasts generate an angiopermissive, provisional extracellular matrix (ECM). Unlike cancers, wounds naturally resolve via blood vessel regression and ECM maturation, which are essential for reestablishing tissue homeostasis. Mechanisms guiding wound resolution are poorly understood; one candidate regulator is pigment epithelium-derived factor (PEDF), a secreted glycoprotein. PEDF is a potent antiangiogenic in models of pathological angiogenesis and a promising cancer and cardiovascular disease therapeutic, but little is known about its physiological function. To examine the roles of PEDF in physiological wound repair, we used a reproducible model of excisional skin wound healing in BALB/c mice. We show that PEDF is abundant in unwounded and healing skin, is produced primarily by dermal fibroblasts, binds to resident microvascular endothelial cells, and accumulates in dermal ECM and epidermis. PEDF transcript and protein levels were low during the inflammatory and proliferative phases of healing but increased in quantity and colocalization with microvasculature during wound resolution. Local antibody inhibition of endogenous PEDF delayed vessel regression and collagen maturation during the remodeling phase. Treatment of wounds with intradermal injections of exogenous, recombinant PEDF inhibited nascent angiogenesis by repressing endothelial proliferation, promoted vascular integrity and function, and increased collagen maturity. These results demonstrate that PEDF contributes to the resolution of healing wounds by causing regression of immature blood vessels and stimulating maturation of the vascular microenvironment, thus promoting a return to tissue homeostasis after injury. PMID:26163443

  8. Pigment epithelium-derived factor as a multifunctional regulator of wound healing.

    Science.gov (United States)

    Wietecha, Mateusz S; Król, Mateusz J; Michalczyk, Elizabeth R; Chen, Lin; Gettins, Peter G; DiPietro, Luisa A

    2015-09-01

    During dermal wound repair, hypoxia-driven proliferation results in dense but highly permeable, disorganized microvascular networks, similar to those in solid tumors. Concurrently, activated dermal fibroblasts generate an angiopermissive, provisional extracellular matrix (ECM). Unlike cancers, wounds naturally resolve via blood vessel regression and ECM maturation, which are essential for reestablishing tissue homeostasis. Mechanisms guiding wound resolution are poorly understood; one candidate regulator is pigment epithelium-derived factor (PEDF), a secreted glycoprotein. PEDF is a potent antiangiogenic in models of pathological angiogenesis and a promising cancer and cardiovascular disease therapeutic, but little is known about its physiological function. To examine the roles of PEDF in physiological wound repair, we used a reproducible model of excisional skin wound healing in BALB/c mice. We show that PEDF is abundant in unwounded and healing skin, is produced primarily by dermal fibroblasts, binds to resident microvascular endothelial cells, and accumulates in dermal ECM and epidermis. PEDF transcript and protein levels were low during the inflammatory and proliferative phases of healing but increased in quantity and colocalization with microvasculature during wound resolution. Local antibody inhibition of endogenous PEDF delayed vessel regression and collagen maturation during the remodeling phase. Treatment of wounds with intradermal injections of exogenous, recombinant PEDF inhibited nascent angiogenesis by repressing endothelial proliferation, promoted vascular integrity and function, and increased collagen maturity. These results demonstrate that PEDF contributes to the resolution of healing wounds by causing regression of immature blood vessels and stimulating maturation of the vascular microenvironment, thus promoting a return to tissue homeostasis after injury. Copyright © 2015 the American Physiological Society.

  9. Molecular phylogeny of the antiangiogenic and neurotrophic serpin, pigment epithelium derived factor in vertebrates

    Science.gov (United States)

    Xu, Xuming; Zhang, Samuel Shao-Min; Barnstable, Colin J; Tombran-Tink, Joyce

    2006-01-01

    Background Pigment epithelium derived factor (PEDF), a member of the serpin family, regulates cell proliferation, promotes survival of neurons, and blocks growth of new blood vessels in mammals. Defining the molecular phylogeny of PEDF by bioinformatic analysis is one approach to understanding the link between its gene structure and its function in these biological processes. Results From a comprehensive search of available DNA databases we identified a single PEDF gene in all vertebrate species examined. These included four mammalian and six non-mammalian vertebrate species in which PEDF had not previously been described. A five gene cluster around PEDF was found in an approximate 100 kb region in mammals, birds, and amphibians. In ray-finned fish these genes are scattered over three chromosomes although only one PEDF gene was consistently found. The PEDF gene is absent in invertebrates including Drosophila melanogaster (D. melanogaster), Caenorhabditis elegans (C. elegans), and sea squirt (C. intestinalis). The PEDF gene is transcribed in all vertebrate phyla, suggesting it is biologically active throughout vertebrate evolution. The multiple actions of PEDF are likely conserved in evolution since it has the same gene structure across phyla, although the size of the gene ranges from 48.3 kb in X. tropicalis to 2.9 kb in fugu, with human PEDF at a size of 15.6 kb. A strong similarity in the proximal 200 bp of the PEDF promoter in mammals suggests the existence of a possible regulatory region across phyla. Using a non-synonymous/synonymous substitution rate ratio we show that mammalian and fish PEDFs have similar ratios of vertebrates and our studies suggest that the regulation and biological actions of this gene are preserved across vertebrates. This comprehensive analysis of the PEDF gene across phyla provides new information that will aid further characterization of common functional motifs of this serpin in biological processes. PMID:17020603

  10. Molecular phylogeny of the antiangiogenic and neurotrophic serpin, pigment epithelium derived factor in vertebrates

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    Barnstable Colin J

    2006-10-01

    Full Text Available Abstract Background Pigment epithelium derived factor (PEDF, a member of the serpin family, regulates cell proliferation, promotes survival of neurons, and blocks growth of new blood vessels in mammals. Defining the molecular phylogeny of PEDF by bioinformatic analysis is one approach to understanding the link between its gene structure and its function in these biological processes. Results From a comprehensive search of available DNA databases we identified a single PEDF gene in all vertebrate species examined. These included four mammalian and six non-mammalian vertebrate species in which PEDF had not previously been described. A five gene cluster around PEDF was found in an approximate 100 kb region in mammals, birds, and amphibians. In ray-finned fish these genes are scattered over three chromosomes although only one PEDF gene was consistently found. The PEDF gene is absent in invertebrates including Drosophila melanogaster (D. melanogaster, Caenorhabditis elegans (C. elegans, and sea squirt (C. intestinalis. The PEDF gene is transcribed in all vertebrate phyla, suggesting it is biologically active throughout vertebrate evolution. The multiple actions of PEDF are likely conserved in evolution since it has the same gene structure across phyla, although the size of the gene ranges from 48.3 kb in X. tropicalis to 2.9 kb in fugu, with human PEDF at a size of 15.6 kb. A strong similarity in the proximal 200 bp of the PEDF promoter in mammals suggests the existence of a possible regulatory region across phyla. Using a non-synonymous/synonymous substitution rate ratio we show that mammalian and fish PEDFs have similar ratios of Conclusion The PEDF gene first appears in vertebrates and our studies suggest that the regulation and biological actions of this gene are preserved across vertebrates. This comprehensive analysis of the PEDF gene across phyla provides new information that will aid further characterization of common functional motifs of

  11. [Effect of cryotherapy over the expression of vascular endothelial growth factor and pigment epithelium-derived factor].

    Science.gov (United States)

    Toscano-Garibay, Julia Dolores; Quiroz-Mercado, Hugo; Espitia-Pinzón, Clara; Gil-Carrasco, Félix; Flores-Estrada, José Javier

    2014-01-01

    Cryotherapy is a no invasive technique that uses intense cold to freeze and destroy cancer tissues. There are no descriptions of its effects over the expression of vascular endothelial growth factor and pigment epithelium-derived factor. Experimental study in cryogenic spot were applied in the right sclera of twelve pigs for ten minutes. Other 3 pigs were used as normal controls. Animals were sacrificed at 7, 14 and 21 and the tissues of choriodes and retina were dissected in areas of approximately 1 cm2 surrounding cryogenic spots. Expression levels of vascular endothelial growth factor and pigment epithelium-derived factor were determined analyzed using polymerase chain reaction coupled to reverse-transcription. Vascular endothelial growth factor was significantly downregulated (24%, p< 0.05) seven days post-treatment meanwhile pigment epithelium-derived factor levels increased 44.8% (p< 0.05) as compared to normal controls (untreated). Both vascular endothelial growth factor and pigment epithelium-derived factor levels remain the same until day 14 but returned to basal expression at day 21. This work expose the relation of cryotherapy with the expression of two factors related to angiogenesis. RESULTS showed significant changes on the expression of vascular endothelial growth factor and pigment epithelium-derived factor illustrating that both proteins are regulated in response to cryogenic treatment in relatively short periods (21 days).

  12. Automated segmentation of serous pigment epithelium detachment in SD-OCT images

    Science.gov (United States)

    Sun, Zhuli; Shi, Fei; Xiang, Dehui; Chen, Haoyu; Chen, Xinjian

    2015-03-01

    Pigment epithelium detachment (PED) is an important clinical manifestation of multiple chorio-retinal disease processes, which can cause the loss of central vision. A 3-D method is proposed to automatically segment serous PED in SD-OCT images. The proposed method consists of five steps: first, a curvature anisotropic diffusion filter is applied to remove speckle noise. Second, the graph search method is applied for abnormal retinal layer segmentation associated with retinal pigment epithelium (RPE) deformation. During this process, Bruch's membrane, which doesn't show in the SD-OCT images, is estimated with the convex hull algorithm. Third, the foreground and background seeds are automatically obtained from retinal layer segmentation result. Fourth, the serous PED is segmented based on the graph cut method. Finally, a post-processing step is applied to remove false positive regions based on mathematical morphology. The proposed method was tested on 20 SD-OCT volumes from 20 patients diagnosed with serous PED. The average true positive volume fraction (TPVF), false positive volume fraction (FPVF), dice similarity coefficient (DSC) and positive predictive value (PPV) are 97.19%, 0.03%, 96.34% and 95.59%, respectively. Linear regression analysis shows a strong correlation (r = 0.975) comparing the segmented PED volumes with the ground truth labeled by an ophthalmology expert. The proposed method can provide clinicians with accurate quantitative information, including shape, size and position of the PED regions, which can assist diagnose and treatment.

  13. Complement factor H, vitronectin, and opticin are tyrosine-sulfated proteins of the retinal pigment epithelium.

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    Yogita Kanan

    Full Text Available Lack of tyrosine sulfation of ocular proteins results in disorganized photoreceptor structure and drastically reduced visual function, demonstrating the importance of this post-translational modification to vision. To understand the role that tyrosine sulfation plays in the function of ocular proteins, we identified some tyrosine-sulfated proteins in the retinal pigment epithelium using two independent methods, immuno-affinity column purification with an anti-sulfotyrosine specific antibody and computer-based sequence analysis of retinal pigment epithelium secretome by means of the prediction program Sulfinator. Radioactive labeling followed by thin layer electrophoresis revealed that three proteins, vitronectin, opticin, and complement factor H (CFH, were post-translationally modified by tyrosine sulfation. The identification of vitronectin and CFH as tyrosine-sulfated proteins is significant, since both are deposited in drusen in the eyes of patients with age-related macular degeneration (AMD. Furthermore, mutations in CFH have been determined to be a major risk factor in the development of AMD. Future studies that seek to understand the role of CFH in the development of AMD should take into account the role that tyrosine sulfation plays in the interaction of this protein with its partners, and examine whether modulating sulfation provides a potential therapeutic target.

  14. Magnetic Nanoparticles as Intraocular Drug Delivery System to Target Retinal Pigmented Epithelium (RPE

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    Martina Giannaccini

    2014-01-01

    Full Text Available One of the most challenging efforts in drug delivery is the targeting of the eye. The eye structure and barriers render this organ poorly permeable to drugs. Quite recently the entrance of nanoscience in ocular drug delivery has improved the penetration and half-life of drugs, especially in the anterior eye chamber, while targeting the posterior chamber is still an open issue. The retina and the retinal pigment epithelium/choroid tissues, located in the posterior eye chamber, are responsible for the majority of blindness both in childhood and adulthood. In the present study, we used magnetic nanoparticles (MNPs as a nanotool for ocular drug delivery that is capable of specific localization in the retinal pigmented epithelium (RPE layer. We demonstrate that, following intraocular injection in Xenopus embryos, MNPs localize specifically in RPE where they are retained for several days. The specificity of the localization did not depend on particle size and surface properties of the MNPs used in this work. Moreover, through similar experiments in zebrafish, we demonstrated that the targeting of RPE by the nanoparticles is not specific for the Xenopus species.

  15. Regulation of estrogen receptors and MMP-2 expression by estrogens in human retinal pigment epithelium.

    Science.gov (United States)

    Marin-Castaño, Maria E; Elliot, Sharon J; Potier, Mylen; Karl, Michael; Striker, Liliane J; Striker, Gary E; Csaky, Karl G; Cousins, Scott W

    2003-01-01

    Age-related macular degeneration (ARMD) is characterized by progressive thickening and accumulation of various lipid-rich extracellular matrix (ECM) deposits under the retinal pigment epithelium (RPE). ECM dysregulation probably contributes to the pathologic course of ARMD. By activating estrogen receptors (ERs), estrogens regulate the expression of genes relevant in the turnover of ECM, among them matrix metalloproteinase (MMP)-2. Estrogen deficiency may predispose to dysregulated synthesis and degradation of ECM, leading to accumulation of collagens and other proteins between the RPE and its basement membrane. The purposes in the current study were to confirm the expression of ERs in human RPE, to elucidate whether these ERs are functional, and to test whether 17beta-estradiol (E(2)) regulates expression of ERs and MMP-2. Expression of ERs was examined in freshly isolated human RPE monolayer and in cultured human RPE cells, by using total RNA for RT-PCR and protein extracts for Western blot analysis. Supernatants were collected from freshly isolated human RPE and from cultured human RPE to assess MMP-2 activity by zymography and protein expression by Western blot. The transcriptional activity of ERs was studied in transfection experiments with an estrogen-responsive reporter construct. All these studies were preformed in the presence or absence of E(2) (10(-11) and 10(-7) M). Human RPE isolated from female and male individuals expressed both ER subtypes alpha and beta at the mRNA and protein levels. Treatment of cultured RPE cells with 10(-10) M E(2) increased expression of mRNA and protein of both receptor subtypes. E(2) (10(-10) M) also increased MMP-2 activity (approximately 2.2-fold) and protein expression (approximately 2.5-fold). In contrast, there was no change in ER levels and MMP-2 activity at higher E(2) concentrations (10(-8) M), compared with baseline. Preincubation of cells with 10(-7) M pyrrolidinedithiocarbamate (PDTC), an inhibitor of nuclear

  16. The pineal gland does not control rod outer segment shedding and phagocytosis in the rat retina and pigment epithelium.

    Science.gov (United States)

    Tamai, M; Teirstein, P; Goldman, A; O'Brien, P; Chader, G

    1978-06-01

    Diurnal patterns of retinal outer segment shedding and phagocytosis by the pigment epithelium were examined in pinealectomized, superior-cervical-ganglionectomized, and sham-operated rats. Phagocytosis was quantitatively similar in all groups. Sharp increases in the number of large phagosomes were observed soon after lights were turned on in the tree sets of animals. Pinealectomized animals kept in constant darkness over a 24 hr period also exhibited normal shedding patterns. Our results suggest that the pineal does not exert a major influence on the daily rhythms of shedding and phagocytosis observed in the retina-pigment epithelium unit.

  17. 高级糖基化终末产物对人视网膜色素上皮细胞的作用机制研究%Advanced glycosylation end products and human retinal pigment epithelium cells

    Institute of Scientific and Technical Information of China (English)

    黄焱; 周敏; 郑卫东; 徐国兴

    2013-01-01

    目的 探讨高级糖基化终末产物(AGEs)对人视网膜色素上皮(RPE)细胞的作用机制.方法 原代培养人RPE细胞,在传代细胞生长状态良好的情况下,无血清的Dulbecco改良Eagle培养基同步化24 h,进行分组:(1)C组:BSA浓度为0.1 g/L,各作用24、48 h,分别为C1、C2组;(2)NC组:葡萄糖浓度为5.6 mmol/L,各作用24、48 h,分别为NC1、NC2组;(3)A组:AGEs浓度分别为0.1、0.2、0.4 g/L,各作用24、48 h,作用24 h依次为A1组、A2组、A3组,作用48 h依次为A4组、A5组、A6组.免疫组织化学检测AGEs受体(RAGE)、过氧化物酶体增生物激活受体γ辅助激活因子-1α(PGC-1α)和血管内皮生长因子(VEGF)蛋白的表达;激光共聚焦显微镜检测核因子-κB (NF-κB)的活化.通过图像分析软件IPP6.0和统计软件SPSS 17.0进行定量分析.结果 A组RPE细胞较C组和NC组RAGE、PGC-1α和VEGF蛋白的表达明显增加,且随着AGEs浓度的升高和刺激时间的延长而增加(F=294.5、228.3、241.5,P<0.05);随着AGEs浓度的升高和刺激时间的延长,NF-κB的活化增加.结论 AGEs的堆积可导致其受体RAGE在RPE细胞表达增加,并促进核转录共同激活因子PGC-1α蛋白的表达和NF-cB的活化,促进RPE细胞VEGF的分泌.%Objective To study the effect of advanced glycosylation end products (AGEs) on human retinal pigment epithelium (RPE) cells.Methods Human primary RPE cells were cultured in basal and different concentrations of AGEs with different times.The cells were divided into several groups as follows:group C (control):bovine serum albumin 0.1 g/L,24 hours (C1) and 48 hours (C2); group NC (normal control):basal culture medium with 5.6 mmol/L of glucose,24 hours (NC1) and 48 hours (NC2) ; group A (AGEs):0.1 g/L,24 hours and 48 hours,A1 and A4 ; 0.2 g/L,24 hours and 48 hours,A2 and A5 ; 0.4 g/L,24 hours and 48 hours,A3 and A6.Immunohistochemistry analysis was used to study the protein expression of receptor for AGEs (RAGE

  18. Effects of extremely low frequency electromagnetic fields on human retinal pigment epithelium cells%极低频电磁场对体外培养人视网膜色素上皮细胞的影响

    Institute of Scientific and Technical Information of China (English)

    王洁; 朱煌; 杜尔罡

    2015-01-01

    Objective To investigate pathological changes in the molecules of human retinal pigment epithelium (hRPE) exposed to an extremely low frequency electromagnetic field (ELF-EMF),and study its possible significance in the occurrence and development of myopia.Methods In this experimental study,the experimental group was composed of hRPE exposed to 50 Hz electromagnetic fields; the untreated group was composed of hRPE without exposure.The changes in hRPE cell morphology were observed and cell proliferation in hRPE was measured by a CCK8 assay.The expressions of matrix metallo-proteinase-2 (MMP-2),tissue inhibitor of metalloproteinase 2 (TIMP-2),transforming growth factor-β2 (TGF-β2) and fibroblast growth factor 2 (FGF-2) mRNA in hRPE were detected by reverse transcription-polymerase chain reaction (RT-PCR).The concentrations of TGF-β2 and FGF-2 in the culture medium of hRPE were assayed by enzyme-linked immunosorbent assay (ELISA).The difference between the two group using independent t test.Results hRPE cell morphology changed,and the proliferation of hRPE was inhibited (t=-7.069,-3.652,-6.974,P< 0.05).The mRNA expressions of MMP-2,TIMP-2 and TGF-β2 were up-regulated significantly (t=10.562,6.277,4.940,P<0.01).However,the mRNA expression of FGF-2 was down-regulated significantly (t=-6.905,P<0.01).The results of ELISA indicated that after exposure to ELF-EMF,the expression of TGF-β2 in hRPE supernatant medium was up-regulated significantly (t=-4.079,P< 0.05).However,the expression of FGF-2 in hRPE supernatant medium was down-regulated (t=4.441,P<0.05).Conclusion ELF-EMF changed the proliferation of hRPE,and also changed the expressions of MMP-2,TIMP-2,TGF-β2 and FGF-2 mRNA in hRPE,which might induce the occurrence of myopia through pathological changes in the molecules of hRPE.%目的 研究极低频电磁场(ELF-EMF)作用下体外培养的人视网膜色素上皮细胞(hRPE)的分子病理改变,探讨其在近视发生发展

  19. Photoreceptors repair by autologous transplantation of retinal pigment epithelium and partial-thickness choroid graft in rabbits.

    Science.gov (United States)

    Zhang, Taoran; Hu, Yuntao; Li, Ying; Wu, Jianguo; Zhao, Lin; Wang, Changguan; Liu, Yuling; Yin, Zhengqin; Ma, Zhizhong

    2009-06-01

    To investigate whether autologous retinal pigment epithelium (RPE) and a partial-thickness graft can repair degenerated photoreceptors overlying a mechanically damaged Bruch's membrane. Twenty-one pigmented rabbits were used in the study. Abrasive debridement of the RPE was performed with a metal cannula after superior retinal bleb detachment in 20 rabbits. The graft was prepared beneath the inferior retina and was transplanted to the debridement area 14 days later. Debridement-only sites served as the control. Tissue sections were evaluated by light microscopy and transmission electron microscopy at 7 days, 1 month, and 3 months after transplantation, corresponding to 21 days, 45 days, and 3 months after debridement, respectively. When analyzed at 7 days after transplantation, short buds of inner segment with regularly organized outer nuclear layer were observed. The outer segments (OS) were of insufficient length to be observed, but by 1 and 3 months, a significant elongation of the OS was detected. In control retinas from 21 days (corresponding to 7 days after transplantation) to 3 months after RPE debridement, the outer nuclear layer cells were disorganized and diminished. This study showed that autologous RPE and partial-thickness choroid graft have the capacity not only to support photoreceptor cell survival, but also to initiate early repair mechanisms, as exhibited by outer segment regeneration.

  20. G-quartet oligonucleotide mediated delivery of proteins into photoreceptors and retinal pigment epithelium via intravitreal injection.

    Science.gov (United States)

    Leaderer, Derek; Cashman, Siobhan M; Kumar-Singh, Rajendra

    2016-04-01

    There is currently no available method to efficiently deliver proteins across the plasma membrane of photoreceptor or retinal pigment epithelium (RPE) cells in vivo. Thus, current clinical application of recombinant proteins in ophthalmology is limited to the use of proteins that perform their biological function extracellularly. The ability to traverse biological membranes would enable the mobilization of a significantly larger number of proteins with previously well characterized properties. Nucleolin is abundantly present on the surface of rapidly dividing cells including cancer cells. Surprisingly, nucleolin is also present on the surface of photoreceptor cell bodies. Here we investigated whether nucleolin can be utilized as a gateway for the delivery of proteins into retinal cells following intravitreal injection. AS1411 is a G-quartet aptamer capable of targeting nucleolin. Subsequent to intravitreal injection, fluorescently labeled AS1411 localized to various retinal cell types including the photoreceptors and RPE. AS1411 linked to streptavidin (a ∼50 kDa protein) via a biotin bridge enabled the uptake of Streptavidin into photoreceptors and RPE. AS1411-Streptavidin conjugate applied topically to the cornea allowed for uptake of the conjugate into the nucleus and cytoplasm of corneal endothelial cells. Clinical relevance of AS1411 as a delivery vehicle was strongly indicated by demonstration of the presence of cell surface nucleolin on the photoreceptors, inner neurons and ganglion cells of human retina. These data support exploration of AS1411 as a means of delivering therapeutic proteins to diseased retina.

  1. L-cystein protects the pigment epithelium from acute sodium iodate toxicity.

    Science.gov (United States)

    Heike, M; Marmor, M F

    1990-08-01

    Intravenous sodium iodate damages the retinal pigment epithelium, causing immediate loss of the electroretinogram c-wave and eventual pigmentary retinopathy. L-cystein, an agent that enhances the c-wave, has been reported to prevent the late development of pigmentary degeneration. We found in rabbits that L-cystein given 30 min before, or simultaneously with (but not 30 min after) sodium iodate also blocks the loss of the c-wave. This result occurred at doses of L-cystein lower than those needed to produce enhancement of the c-wave, suggesting that these two actions of L-cystein may be independent. The iodate-blocking action of L-cystein may depend on chemical interaction.

  2. Pigment epithelium-derived factor (PEDF): a novel trophoblast-derived factor limiting feto-placental angiogenesis in late pregnancy.

    Science.gov (United States)

    Loegl, Jelena; Nussbaumer, Erika; Hiden, Ursula; Majali-Martinez, Alejandro; Ghaffari-Tabrizi-Wizy, Nassim; Cvitic, Silvija; Lang, Ingrid; Desoye, Gernot; Huppertz, Berthold

    2016-07-01

    The rapidly expanding feto-placental vasculature needs tight control by paracrine and endocrine mechanisms. Here, we focused on paracrine influence by trophoblast, the placental epithelium. We aimed to identify differences in regulation of feto-placental angiogenesis in early versus late pregnancy. To this end, the effect of conditioned media (CM) from early and late pregnancy human trophoblast was tested on network formation, migration and proliferation of human feto-placental endothelial cells. Only CM of late pregnancy trophoblast reduced network formation and migration. Screening of trophoblast transcriptome for anti-angiogenic candidates identified pigment epithelium-derived factor (PEDF) with higher expression and protein secretion in late pregnancy trophoblast. Addition of a PEDF-neutralizing antibody restored the anti-angiogenic effect of CM from late pregnancy trophoblast. Notably, human recombinant PEDF reduced network formation only in combination with VEGF. Also in the CAM assay, the combination of PEDF with VEGF reduced branching of vessels below control levels. Analysis of phosphorylation of ERK1/2 and FAK, two key players in VEGF-induced proliferation and migration, revealed that PEDF altered VEGF signaling, while PEDF alone did not affect phosphorylation of ERK1/2 and FAK. These data suggest that the trophoblast-derived anti-angiogenic molecule PEDF is involved in restricting growth and expansion of the feto-placental endothelium predominantly in late pregnancy and targets to modulate the intracellular effect of VEGF.

  3. Fucoidan reduces secretion and expression of vascular endothelial growth factor in the retinal pigment epithelium and reduces angiogenesis in vitro.

    Directory of Open Access Journals (Sweden)

    Michaela Dithmer

    Full Text Available Fucoidan is a polysaccharide isolated from brown algae which is of current interest for anti-tumor therapy. In this study, we investigated the effect of fucoidan on the retinal pigment epithelium (RPE, looking at physiology, vascular endothelial growth factor (VEGF secretion, and angiogenesis, thus investigating a potential use of fucoidan for the treatment of exudative age-related macular degeneration. For this study, human RPE cell line ARPE-19 and primary porcine RPE cells were used, as well as RPE/choroid perfusion organ cultures. The effect of fucoidan on RPE cells was investigated with methyl thiazolyl tetrazolium--assay, trypan blue exclusion assay, phagocytosis assay and a wound healing assay. VEGF expression was evaluated in immunocytochemistry and Western blot, VEGF secretion was evaluated in ELISA. The effect of fucoidan on angiogenesis was tested in a Matrigel assay using calcein-AM vital staining, evaluated by confocal laser scanning microcopy and quantitative image analysis. Fucoidan displays no toxicity and does not diminish proliferation or phagocytosis, but reduces wound healing in RPE cells. Fucoidan decreases VEGF secretion in RPE/choroid explants and RPE cells. Furthermore, it diminishes VEGF expression in RPE cells even when co-applied with bevacizumab. Furthermore, fucoidan reduces RPE-supernatant- and VEGF-induced angiogenesis of peripheral endothelial cells. In conclusion, fucoidan is a non-toxic agent that reduces VEGF expression and angiogenesis in vitro and may be of interest for further studies as a potential therapy against exudative age-related macular degeneration.

  4. iPSC-Derived Retinal Pigment Epithelium Allografts Do Not Elicit Detrimental Effects in Rats: A Follow-Up Study

    Directory of Open Access Journals (Sweden)

    Peter D. Westenskow

    2016-01-01

    Full Text Available Phototransduction is accomplished in the retina by photoreceptor neurons and retinal pigment epithelium (RPE cells. Photoreceptors rely heavily on the RPE, and death or dysfunction of RPE is characteristic of age-related macular degeneration (AMD, a very common neurodegenerative disease for which no cure exists. RPE replacement is a promising therapeutic intervention for AMD, and large numbers of RPE cells can be generated from pluripotent stem cells. However, questions persist regarding iPSC-derived RPE (iPS-RPE viability, immunogenicity, and tumorigenesis potential. We showed previously that iPS-RPE prevent photoreceptor atrophy in dystrophic rats up until 24 weeks after implantation. In this follow-up study, we longitudinally monitored the same implanted iPS-RPE, in the same animals. We observed no gross abnormalities in the eyes, livers, spleens, brains, and blood in aging rats with iPSC-RPE grafts. iPS-RPE cells that integrated into the subretinal space outlived the photoreceptors and survived for as long as 2 1/2 years while nonintegrating RPE cells were ingested by host macrophages. Both populations could be distinguished using immunohistochemistry and electron microscopy. iPSC-RPE could be isolated from the grafts and maintained in culture; these cells also phagocytosed isolated photoreceptor outer segments. We conclude that iPS-RPE grafts remain viable and do not induce any obvious associated pathological changes.

  5. Protective effect of genistein on human retinal pigment epithelium cell cultured in high glucose%金雀异黄素对高糖诱导的人RPE细胞损伤的保护作用

    Institute of Scientific and Technical Information of China (English)

    帅捷; 洪瑾; 袁志兰

    2007-01-01

    目的 探讨金雀异黄素(genistein,Gen)对高糖诱导的人视网膜色素上皮(retinal pigment epithelium,RPE)细胞的保护作用.方法 培养人RPE细胞,分别以Gen 0 μmol·L-1、50 μmol·L-1、100 μmol·L-1、200 μmol·L-1的药物浓度作用高糖(33 mmol·L-1)培养的RPE细胞48 h,噻唑蓝比色法检测细胞活性;流式细胞仪检测细胞周期;激光共聚焦显微镜检测细胞内活性氧(reactive oxygen species,ROS)水平;黄嘌呤氧化酶法测定细胞内超氧化物歧化酶(SOD)活性.结果 高糖组细胞活力(0.308±0.022)明显低于正常对照组(0.424±0.014)(P<0.01);高糖+Gen组细胞活力较高糖组升高(P<0.05),且随Gen浓度增大,细胞活力增加更明显.与正常对照组比较,高糖组细胞增殖受到抑制,被阻滞于S期和G2期;与高糖组比较,Gen可减轻高糖对细胞增殖的抑制作用.与正常对照组比较,高糖组细胞内ROS的产生明显增多;Gen以浓度依赖方式抑制高糖组RPE细胞内ROS的产生.与正常对照组(31.04±0.02)比较,高糖组SOD活性(12.32±0.02)显著降低(P<0.01);与高糖组比较,高糖+Gen组SOD活性随Gen浓度的增加而升高(均P<0.05).结论 Gen可保护和修复高糖诱导的人RPE细胞的损伤,其作用可能与抗氧化、增强SOD活性有关.

  6. Trafficking of osteonectin by retinal pigment epithelial cells: evidence for basolateral secretion.

    Science.gov (United States)

    Ratnayaka, Arjuna; Paraoan, Luminita; Nelson, Glyn; Spiller, Dave G; White, Michael R H; Hiscott, Paul

    2007-01-01

    Osteonectin is a glycoprotein that modulates several aspects of cellular behaviour including proliferation and adhesion. The retinal pigment epithelium forms a continuous monolayer of polarised cells immediately bellow the neuroretina, and is integral to the homeostasis of photoreceptor cells. While osteonectin is expressed by normal retinal pigment epithelium in situ, its expression is significantly increased in retinal pigment epithelial cells associated with several common retinal diseases. This pattern of expression implies an important role for osteonectin in the biology of retinal pigment epithelial cells. However, the trafficking, processing, and eventual fate of osteonectin in these cells is not clear at present. Although the theoretical report of a leader sequence within the osteonectin open reading frame and its extracellular presence in some tissues indirectly support secretion of the protein, there is no direct experimental demonstration of the secretion route to date. As a first step towards understanding the role of osteonectin in retinal pigment epithelium, we studied the intracellular distribution and trafficking of the protein in living cells. Here, we present experimental evidence that a precursor osteonectin fusion protein is targeted to the endoplasmic reticulum/Golgi pathway, with a likely basal secretion in retinal pigment epithelial cells. In addition, we show that the precursor osteonectin protein having the leader sequence masked fails to undergo secretion leading to cell death, a phenotype which may be of relevance not only for retinal pathology, but also for other diseases such as the bone disorder known as pseudoachondroplasia that is associated with a lack of osteonectin secretion.

  7. Regulatory and Functional Connection of Microphthalmia-Associated Transcription Factor and Anti-Metastatic Pigment Epithelium Derived Factor in Melanoma

    Directory of Open Access Journals (Sweden)

    Asunción Fernández-Barral

    2014-06-01

    Full Text Available Pigment epithelium-derived factor (PEDF, a member of the serine protease inhibitor superfamily, has potent anti-metastatic effects in cutaneous melanoma through its direct actions on endothelial and melanoma cells. Here we show that PEDF expression positively correlates with microphthalmia-associated transcription factor (MITF in melanoma cell lines and human samples. High PEDF and MITF expression is characteristic of low aggressive melanomas classified according to molecular and pathological criteria, whereas both factors are decreased in senescent melanocytes and naevi. Importantly, MITF silencing down-regulates PEDF expression in melanoma cell lines and primary melanocytes, suggesting that the correlation in the expression reflects a causal relationship. In agreement, analysis of Chromatin immunoprecipitation coupled to high throughput sequencing (ChIP-seq data sets revealed three MITF binding regions within the first intron of SERPINF1, and reporter assays demonstrated that the binding of MITF to these regions is sufficient to drive transcription. Finally, we demonstrate that exogenous PEDF expression efficiently halts in vitro migration and invasion, as well as in vivo dissemination of melanoma cells induced by MITF silencing. In summary, these results identify PEDF as a novel transcriptional target of MITF and support a relevant functional role for the MITF-PEDF axis in the biology of melanoma.

  8. Anatomical and visual outcomes of ranibizumab injections in retinal pigment epithelium tears

    Directory of Open Access Journals (Sweden)

    Muhammet Kazım Erol

    2015-06-01

    Full Text Available ABSTRACT Purpose: To report the anatomical and visual results in patients diagnosed as having retinal pigment epithelium (RPE tears after receiving ranibizumab injections. Methods: Eyes diagnosed as having RPE tears with a minimum 6-month follow-up were retrospectively evaluated. Each eye was treated with at least three doses of ranibizumab at monthly intervals. Best-corrected visual acuity (BCVA, anterior segment findings, intraocular pressure, and fundus examination results were evaluated during control visits. Color fundus photography, fundus fluorescein angiographies, fundus autofluorescence, and spectral domain optical coherence tomography (SD-OCT images were obtained. The height of pigment epithelial detachment (PED was measured by SD-OCT. Results: Twelve eyes with RPE tears were studied. Nine eyes (75% developed RPE tears during ranibizumab injections for choroidal neovascularization (eight eyes with vascularized PED and one eye with choroidal osteoma, and tears occurred in three eyes before any injections. The median number of ranibizumab injections after diagnosis of RPE tears was 3 (min 2, max 5. In the most recent follow-up visit, there was no statistically significant correlation between the grade of RPE and logMAR of BCVA (p>0.05, r=0.112. Eight of twelve eyes had PED, and seven of these had irregular PED contours before injection therapy. The mean PED height was 447 ± 122 µm. Conclusions: In this series, RPE tears developed mostly after intravitreal anti-VEGF injections for vascularized PED. Increased vertical height and irregular contours of the PEDs can be risk factors for the formation of RPE tears. The continuation of anti-VEGF therapy after tear formation is beneficial for vision improvement in eyes with RPE tears.

  9. Photocoagulation of human retinal pigment epithelium in vitro: unravelling the effects on ARPE-19 by transcriptomics and proteomics.

    Science.gov (United States)

    Tababat-Khani, Poya; de la Torre, Carolina; Canals, Francesc; Bennet, Hedvig; Simo, Rafael; Hernandez, Cristina; Fex, Malin; Agardh, Carl-David; Hansson, Ola; Agardh, Elisabet

    2015-06-01

    Despite the extensive use of retinal photocoagulation for ischaemia and vascular leakage in retinal vascular disease, the molecular mechanisms behind its clinical beneficial effects are still poorly understood. One important target of laser irradiation is the retinal pigment epithelium (RPE). In this study, we aimed at identifying the isolated effects of photocoagulation of RPE at both the mRNA and protein expression levels. Human ARPE-19 cells were exposed to photocoagulation. Gene expression and protein expression were compared to untreated cells using microarray and liquid chromatography-mass spectrometry analysis. Genes and proteins queried by microarray and mass spectrometry were subjected to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database pathway analyses. Laser irradiation resulted in an induction of the cytoprotective heat-shock protein subfamily Hsp70 as well as in a suppression of the vascular permeability factor carbonic anhydrase 9 (CA9). These expression patterns were evident at both the mRNA and protein levels. KEGG pathway analyses revealed genes and proteins involved in cellular turnover, repair and inflammation. By characterizing the transcriptional and translational effects of laser coagulation on the RPE cells in culture, we have revealed responses, which might contribute to some of the beneficial effects obtained by photocoagulation for ischaemia and vascular leakage in retinal vascular disease. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  10. ROCK Inhibition Promotes Attachment, Proliferation, and Wound Closure in Human Embryonic Stem Cell–Derived Retinal Pigmented Epithelium

    Science.gov (United States)

    Croze, Roxanne H.; Thi, William J.; Clegg, Dennis O.

    2016-01-01

    Purpose Nonexudative (dry) age-related macular degeneration (AMD), a leading cause of blindness in the elderly, is associated with the loss of retinal pigmented epithelium (RPE) cells and the development of geographic atrophy, which are areas devoid of RPE cells and photoreceptors. One possible treatment option would be to stimulate RPE attachment and proliferation to replace dying/dysfunctional RPE and bring about wound repair. Clinical trials are underway testing injections of RPE cells derived from pluripotent stem cells to determine their safety and efficacy in treating AMD. However, the factors regulating RPE responses to AMD-associated lesions are not well understood. Here, we use cell culture to investigate the role of RhoA coiled coil kinases (ROCKs) in human embryonic stem cell–derived RPE (hESC-RPE) attachment, proliferation, and wound closure. Methods H9 hESC were spontaneously differentiated into RPE cells. hESC-RPE cells were treated with a pan ROCK1/2 or a ROCK2 only inhibitor; attachment, and proliferation and cell size within an in vitro scratch assay were examined. Results Pharmacological inhibition of ROCKs promoted hESC-RPE attachment and proliferation, and increased the rate of closure of in vitro wounds. ROCK inhibition decreased phosphorylation of cofilin and myosin light chain, suggesting that regulation of the cytoskeleton underlies the mechanism of action of ROCK inhibition. Conclusions ROCK inhibition promotes attachment, proliferation, and wound closure in H9 hESC-RPE cells. ROCK isoforms may have different roles in wound healing. Translational Relevance Modulation of the ROCK-cytoskeletal axis has potential in stimulating wound repair in transplanted RPE cells and attachment in cellular therapies. PMID:27917311

  11. 视网膜脱离外路显微手术中色素颗粒进入玻璃体临床观察%Clinical observation of intravitreal dispersion of retinal pigment epithelium cells during external approach microsurgery of retinal detachment

    Institute of Scientific and Technical Information of China (English)

    许大玲; 刘文; 霍鸣; 罗彤

    2008-01-01

    Objective It is a common phenomenon that a lot of pigmented debris disperses into vitreous cavity through retinal breaks during the cryotherapy or location of retinal breaks while the external approach microsurgery for rhegmatogenous retinal detachment (RRD) is performed.The study was designed for observing the surgical outcomes of this complication.Methods A consecutive thirty-eight patients (39eyes) with RRD,which were found intravitreal dispersion of retinal pigment epithelium cells during external approach mierosurgery of retinal detachment,were retrospectively analyzed.All of them were primary RRD and proliferative vitreoretinopathy (PVR) was classified equal to or under B.The numbers of average retinal breaks were 2.67.The size of the retinal break ranged from 1/7DD to 1.5 clock hour.The scleral buckling was performed in 11 eyes,and the circling and buckling in 28 eyes.Results The following-up times were 6 months at least.The retinal pigment epithelium cells of intravitreal dispersion gradually decreased and faded away.Retinal reattachment was achieved in 38 eyes (96.7%) after the primary surgery.A new retinal break was formed in one case and caused retinal redetachment.After vitreous surgery,this case got retinal reattachment.The final rate of reattachment was 100%.The excessive cryotherapy and severe PVR were not occurred.Conclusion As long as the holes or tears are closed effectively,the intravitreal dispersion of retinal pigment epithelium cells during external approach microsurgery of retinal detachment doesn't cause PVR develop or aggravate.The surgical outcomes are excellent.%目的 观察在视网膜脱离外路显微手术中做视网膜裂孔冷凝或定位时,色素颗粒从裂孔播散入玻璃体腔,对手术效果的影响.方法 回顾性统计分析视网膜脱离外路显微手术中有色素颗粒从裂孔涌人玻璃体腔的连续38例39只眼,均是初发裂孔性视网膜脱离患者,PVR分级为B级以下.平均每只眼裂孔数2.67

  12. Applying photoacoustics to quantification of melanin concentration in retinal pigment epithelium (Conference Presentation)

    Science.gov (United States)

    Shu, Xiao; Zhang, Hao F.; Liu, Wenzhong

    2016-03-01

    The melanin in the retinal pigment epithelium (RPE) protects retina and other ocular tissues by photo-screening and acting as antioxidant and free radical scavenger. It helps maintain normal visual functions since human eye is subjected to lifelong high oxygen stress and photon exposure. Loss of the RPE melanin weakens the protection mechanism and jeopardizes ocular health. Local decrease in the RPE melanin concentration is believed to be both a cause and a sign of early-stage age-related macular degeneration (AMD), the leading blinding disease in developed world. Current technology cannot quantitatively measure the RPE melanin concentration which might be a promising marker in early AMD screening. Photoacoustic ophthalmoscopy (PAOM), as an emerging optical absorption-based imaging technology, can potentially be applied to measure the RPE melanin concentration if the dependence of the detectable photoacoustic (PA) signal amplitudes on the RPE melanin concentrations is verified. In this study, we tested the feasibility of using PA signal ratio from RPE melanin and the nearby retinal blood vessels as an indicator of the RPE melanin variation. A novel whole eye optical model was designed and Monte Carlo modeling of light (MCML) was employed. We examined the influences on quantification from PAOM axial resolution, the depth and diameter of the retinal blood vessel, and the RPE thickness. The results show that the scheme is robust to individual histological and illumination variations. This study suggests that PAOM is capable of quantitatively measuring the RPE melanin concentration in vivo.

  13. Choroidal neovascularization induced by immunogenic alteration of the retinal pigment epithelium in dengue Fever.

    Science.gov (United States)

    Veloso, Carlos Eduardo; Schmidt-Erfurth, Ursula; Nehemy, Márcio B

    2015-01-01

    To report the first case of choroidal neovascularization (CNV) secondary to dengue fever. A 54-year-old female was referred to our department with blurred vision and metamorphopsia in her left eye. Two weeks earlier, she had presented all of the classic symptoms of dengue fever including a positive serology. Her best-corrected visual acuity (BCVA) was 20/150 in the left eye. She underwent a fundus examination, fluorescein angiography (FA) and spectral domain optical coherence tomography. All findings were consistent with CNV secondary to dengue fever. FA revealed a classic CNV associated with focal retinal pigment epithelium (RPE) destruction and detachment. Three consecutive monthly injections of intravitreal ranibizumab resulted in functional and anatomical improvement for as long as 6 months with a BCVA of 20/25. However, CNV recurred 2 years later, again with an improvement after ranibizumab therapy, but with persistence of a fibrovascular RPE detachment, highlighting the pathomechanism of a classic CNV formation. Maculopathy in dengue fever may be followed by CNV as a result of the immunologic alteration of the RPE. Physicians should be aware of this manifestation to be able to initiate adequate treatment with excellent functional and anatomical results.

  14. Monte Carlo investigation on quantifying the retinal pigment epithelium melanin concentration by photoacoustic ophthalmoscopy.

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    Shu, Xiao; Liu, Wenzhong; Zhang, Hao F

    2015-10-01

    The retinal pigment epithelium (RPE) melanin plays an important role in maintaining normal visual functions. A decrease in the RPE melanin concentration with aging is believed to be associated with several blinding diseases, including age-related macular degeneration. Quantifying the RPE melanin noninvasively is therefore important in evaluating the retinal health and aging conditions. Photoacoustic ophthalmoscopy (PAOM), as an optical absorption-based imaging technology, can potentially be applied to measure variations in the RPE melanin if the relationship between the detected photoacoustic (PA) signal amplitudes and the RPE melanin concentrations can be established. In this work, we tested the feasibility of using PA signals from retinal blood vessels as references to measure RPE melanin variation using Monte Carlo (MC) simulation. The influences from PAOM axial resolution, the depth and diameter of the retinal blood vessel, and the RPE thickness were examined. We proposed a calibration scheme by relating detected PA signals to the RPE melanin concentrations, and we found that the scheme is robust to these tested parameters. This study suggests that PAOM has the capability of quantitatively measuring the RPE melanin in vivo.

  15. Defining the proteome of human iris, ciliary body, retinal pigment epithelium, and choroid.

    Science.gov (United States)

    Zhang, Pingbo; Kirby, David; Dufresne, Craig; Chen, Yan; Turner, Randi; Ferri, Sara; Edward, Deepak P; Van Eyk, Jennifer E; Semba, Richard D

    2016-04-01

    The iris is a fine structure that controls the amount of light that enters the eye. The ciliary body controls the shape of the lens and produces aqueous humor. The retinal pigment epithelium and choroid (RPE/choroid) are essential in supporting the retina and absorbing light energy that enters the eye. Proteins were extracted from iris, ciliary body, and RPE/choroid tissues of eyes from five individuals and fractionated using SDS-PAGE. After in-gel digestion, peptides were analyzed using LC-MS/MS on an Orbitrap Elite mass spectrometer. In iris, ciliary body, and RPE/choroid, we identified 2959, 2867, and 2755 nonredundant proteins with peptide and protein false-positive rates of body, and RPE/choroid. Four "missing proteins" were identified in ciliary body based on ≥2 proteotypic peptides. The mass spectrometric proteome database of the human iris, ciliary body, and RPE/choroid may serve as a valuable resource for future investigations of the eye in health and disease. The MS proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifiers PXD001424 and PXD002194.

  16. The Retinome – Defining a reference transcriptome of the adult mammalian retina/retinal pigment epithelium

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    Goetz Thomas

    2004-07-01

    Full Text Available Abstract Background The mammalian retina is a valuable model system to study neuronal biology in health and disease. To obtain insight into intrinsic processes of the retina, great efforts are directed towards the identification and characterization of transcripts with functional relevance to this tissue. Results With the goal to assemble a first genome-wide reference transcriptome of the adult mammalian retina, referred to as the retinome, we have extracted 13,037 non-redundant annotated genes from nearly 500,000 published datasets on redundant retina/retinal pigment epithelium (RPE transcripts. The data were generated from 27 independent studies employing a wide range of molecular and biocomputational approaches. Comparison to known retina-/RPE-specific pathways and established retinal gene networks suggest that the reference retinome may represent up to 90% of the retinal transcripts. We show that the distribution of retinal genes along the chromosomes is not random but exhibits a higher order organization closely following the previously observed clustering of genes with increased expression. Conclusion The genome wide retinome map offers a rational basis for selecting suggestive candidate genes for hereditary as well as complex retinal diseases facilitating elaborate studies into normal and pathological pathways. To make this unique resource freely available we have built a database providing a query interface to the reference retinome 1.

  17. Generation of retinal pigment epithelial cells from human embryonic stem cell-derived spherical neural masses.

    Science.gov (United States)

    Cho, Myung Soo; Kim, Sang Jin; Ku, Seung-Yup; Park, Jung Hyun; Lee, Haksup; Yoo, Dae Hoon; Park, Un Chul; Song, Seul Ae; Choi, Young Min; Yu, Hyeong Gon

    2012-09-01

    Dysfunction and loss of retinal pigment epithelium (RPE) are major pathologic changes observed in various retinal degenerative diseases such as aged-related macular degeneration. RPE generated from human pluripotent stem cells can be a good candidate for RPE replacement therapy. Here, we show the differentiation of human embryonic stem cells (hESCs) toward RPE with the generation of spherical neural masses (SNMs), which are pure masses of hESCs-derived neural precursors. During the early passaging of SNMs, cystic structures arising from opened neural tube-like structures showed pigmented epithelial morphology. These pigmented cells were differentiated into functional RPE by neuroectodermal induction and mechanical purification. Most of the differentiated cells showed typical RPE morphologies, such as a polygonal-shaped epithelial monolayer, and transmission electron microscopy revealed apical microvilli, pigment granules, and tight junctions. These cells also expressed molecular markers of RPE, including Mitf, ZO-1, RPE65, CRALBP, and bestrophin. The generated RPE also showed phagocytosis of isolated bovine photoreceptor outer segment and secreting pigment epithelium-derived factor and vascular endothelial growth factor. Functional RPE could be generated from SNM in our method. Because SNMs have several advantages, including the capability of expansion for long periods without loss of differentiation capability, easy storage and thawing, and no need for feeder cells, our method for RPE differentiation may be used as an efficient strategy for generating functional RPE cells for retinal regeneration therapy.

  18. Phloroglucinol protects retinal pigment epithelium and photoreceptor against all-trans-retinal-induced toxicity and inhibits A2E formation.

    Science.gov (United States)

    Cia, David; Cubizolle, Aurélie; Crauste, Céline; Jacquemot, Nathalie; Guillou, Laurent; Vigor, Claire; Angebault, Claire; Hamel, Christian P; Vercauteren, Joseph; Brabet, Philippe

    2016-09-01

    Among retinal macular diseases, the juvenile recessive Stargardt disease and the age-related degenerative disease arise from carbonyl and oxidative stresses (COS). Both stresses originate from an accumulation of all-trans-retinal (atRAL) and are involved in bisretinoid formation by condensation of atRAL with phosphatidylethanolamine (carbonyl stress) in the photoreceptor and its transformation into lipofuscin bisretinoids (oxidative stress) in the retinal pigment epithelium (RPE). As atRAL and bisretinoid accumulation contribute to RPE and photoreceptor cell death, our goal is to select powerful chemical inhibitors of COS. Here, we describe that phloroglucinol, a natural phenolic compound having anti-COS properties, protects both rat RPE and mouse photoreceptor primary cultures from atRAL-induced cell death and reduces hydrogen peroxide (H2 O2 )-induced damage in RPE in a dose-dependent manner. Mechanistic analyses demonstrate that the protective effect encompasses decrease in atRAL-induced intracellular reactive oxygen species and free atRAL levels. Moreover, we show that phloroglucinol reacts with atRAL to form a chromene adduct which prevents bisretinoid A2E synthesis in vitro. Taken together, these data show that the protective effect of phloroglucinol correlates with its ability to trap atRAL and to prevent its further transformation into deleterious bisretinoids. Phloroglucinol might be a good basis to develop efficient therapeutic derivatives in the treatment of retinal macular diseases.

  19. Complement system dysregulation and inflammation in the retinal pigment epithelium of a mouse model for Stargardt macular degeneration.

    Science.gov (United States)

    Radu, Roxana A; Hu, Jane; Yuan, Quan; Welch, Darcy L; Makshanoff, Jacob; Lloyd, Marcia; McMullen, Stephen; Travis, Gabriel H; Bok, Dean

    2011-05-27

    Accumulation of vitamin A-derived lipofuscin fluorophores in the retinal pigment epithelium (RPE) is a pathologic feature of recessive Stargardt macular dystrophy, a blinding disease caused by dysfunction or loss of the ABCA4 transporter in rods and cones. Age-related macular degeneration, a prevalent blinding disease of the elderly, is strongly associated with mutations in the genes for complement regulatory proteins (CRP), causing chronic inflammation of the RPE. Here we explore the possible relationship between lipofuscin accumulation and complement activation in vivo. Using the abca4(-/-) mouse model for recessive Stargardt, we investigated the role of lipofuscin fluorophores (A2E-lipofuscin) on oxidative stress and complement activation. We observed higher expression of oxidative-stress genes and elevated products of lipid peroxidation in eyes from abca4(-/-) versus wild-type mice. We also observed higher levels of complement-activation products in abca4(-/-) RPE cells. Unexpectedly, expression of multiple CRPs, which protect cells from attack by the complement system, were lower in abca4(-/-) versus wild-type RPE. To test whether acute exposure of healthy RPE cells to A2E-lipofuscin affects oxidative stress and expression of CRPs, we fed cultured fetal-derived human RPE cells with rod outer segments from wild-type or abca4(-/-) retinas. In contrast to RPE cells in abca4(-/-) mice, human RPE cells exposed to abca4(-/-) rod outer segments adaptively increased expression of both oxidative-stress and CRP genes. These results suggest that A2E accumulation causes oxidative stress, complement activation, and down-regulation of protective CRP in the Stargardt mouse model. Thus, Stargardt disease and age-related macular degeneration may both be caused by chronic inflammation of the RPE.

  20. Fine structure of the retinal pigment epithelium in the Port Jackson shark (Heterodontus phillipi).

    Science.gov (United States)

    Braekevelt, C R

    1994-11-01

    The structure of the retinal epithelium (RPE), choriocapillaris and Bruch's membrane (complexus basalis) has been studied by light and electron microscopy in the Port Jackson shark (Heterodontus phillipi). In this elasmobranch the RPE consists of a single layer of low cuboidal cells which show basal (scleral) infolding and apical (vitreal) processes that enclose photoreceptor outer segments. Laterally these epithelial cells are joined by a series of apically located tight junctions. The RPE cells display a large vesicular nucleus, abundant smooth endoplasmic reticulum as well as numerous polysomes and mitochondria. Phagosomes are present, rough endoplasmic reticulum is scarce and myeloid bodies were not observed. Melanosomes are absent over the choroidally located tapetum lucidum, but are not abundant even in extratapetal areas. This paucity of melanosomes probably makes retinomotor movements unimportant. Bruch's membrane or complexus basalis is a pentalaminate structure. The endothelium of the choriocapillaris is thin but minimally fenestrated.

  1. Novel localization of peripherin 2, the photoreceptor-specific retinal degeneration slow protein, in retinal pigment epithelium.

    Science.gov (United States)

    Uhl, Patrizia B; Amann, Barbara; Hauck, Stefanie M; Deeg, Cornelia A

    2015-01-26

    Retinal pigment epithelium (RPE) builds the outer blood-retinal barrier of the eye. Since one typical feature of the autoimmune disease, equine recurrent uveitis (ERU), is the breakdown of this barrier, we recently performed comparative analysis of healthy and uveitic RPE. We identified for the first time peripherin 2, which is responsible for visual perception and retina development, to be localized in RPE. The purpose of this study was therefore to validate our findings by characterizing the expression patterns of peripherin 2 in RPE and retina. We also investigated whether peripherin 2 expression changes in ERU and if it is expressed by the RPE itself. Via immunohistochemistry, significant downregulation of peripherin 2 in uveitic RPE compared to the control was detectable, but there was no difference in healthy and uveitic retina. A further interesting finding was the clear distinction between peripherin 2 and the phagocytosis marker, rhodopsin, in healthy RPE. In conclusion, changes in the expression pattern of peripherin 2 selectively affect RPE, but not retina, in ERU. Moreover, peripherin 2 is clearly detectable in healthy RPE due to both phagocytosis and the expression by the RPE cells themselves. Our novel findings are very promising for better understanding the molecular mechanisms taking place on RPE in uveitis.

  2. Pigment epithelium-derived factor: clinical significance in estrogen-dependent tissues and its potential in cancer therapy

    Science.gov (United States)

    Franco-Chuaire, María Liliana; Ramírez-Clavijo, Sandra; Chuaire-Noack, Lilian

    2015-01-01

    Pigment epithelium-derived factor (PEDF) is a glycoprotein that belongs to the family of non-inhibitory serpins. The broad spectrum of PEDF biological activity is evident when considering its effects in promoting cell survival and proliferation, as well as its antiangiogenic, antitumor, and anti-metastatic properties. Although the structural domains of the PEDF gene that mediate such diverse effects and their mechanisms of action have not been completely elucidated, there is a large body of evidence describing their diverse range of activities; this evidence combined with the regulation of PEDF expression by sex steroids and their receptors have led to the idea that PEDF is not only a diagnostic and prognostic marker for certain diseases such as cancer, but is also a potential therapeutic target. In this manner, this paper aims to generally review the regulation of PEDF expression and PEDF interactions, as well as the findings that relate PEDF to the role of estrogens and estrogen receptors. In addition, this manuscript will review major advances toward potential therapeutic applications of PEDF. PMID:26523216

  3. Novel Localization of Peripherin 2, the Photoreceptor-Specific Retinal Degeneration Slow Protein, in Retinal Pigment Epithelium

    Directory of Open Access Journals (Sweden)

    Patrizia B. Uhl

    2015-01-01

    Full Text Available Retinal pigment epithelium (RPE builds the outer blood-retinal barrier of the eye. Since one typical feature of the autoimmune disease, equine recurrent uveitis (ERU, is the breakdown of this barrier, we recently performed comparative analysis of healthy and uveitic RPE. We identified for the first time peripherin 2, which is responsible for visual perception and retina development, to be localized in RPE. The purpose of this study was therefore to validate our findings by characterizing the expression patterns of peripherin 2 in RPE and retina. We also investigated whether peripherin 2 expression changes in ERU and if it is expressed by the RPE itself. Via immunohistochemistry, significant downregulation of peripherin 2 in uveitic RPE compared to the control was detectable, but there was no difference in healthy and uveitic retina. A further interesting finding was the clear distinction between peripherin 2 and the phagocytosis marker, rhodopsin, in healthy RPE. In conclusion, changes in the expression pattern of peripherin 2 selectively affect RPE, but not retina, in ERU. Moreover, peripherin 2 is clearly detectable in healthy RPE due to both phagocytosis and the expression by the RPE cells themselves. Our novel findings are very promising for better understanding the molecular mechanisms taking place on RPE in uveitis.

  4. Pigment epithelium-derived factor: clinical significance in estrogen-dependent tissues and its potential in cancer therapy

    Directory of Open Access Journals (Sweden)

    María Liliana Franco-Chuaire

    2015-09-01

    Full Text Available Pigment epithelium-derived factor (PEDF is a glycoprotein that belongs to the family of non-inhibitory serpins. The broad spectrum of PEDF biological activity is evident when considering its effects in promoting cell survival and proliferation, as well as its antiangiogenic, antitumor, and anti-metastatic properties. Although the structural domains of the PEDF gene that mediate such diverse effects and their mechanisms of action have not been completely elucidated, there is a large body of evidence describing their diverse range of activities; this evidence combined with the regulation of PEDF expression by sex steroids and their receptors have led to the idea that PEDF is not only a diagnostic and prognostic marker for certain diseases such as cancer, but is also a potential therapeutic target. In this manner, this paper aims to generally review the regulation of PEDF expression and PEDF interactions, as well as the findings that relate PEDF to the role of estrogens and estrogen receptors. In addition, this manuscript will review major advances toward potential therapeutic applications of PEDF.

  5. Pigment Epithelium-Derived Factor Alleviates Tamoxifen-Induced Endometrial Hyperplasia.

    Science.gov (United States)

    Goldberg, Keren; Bar-Joseph, Hadas; Grossman, Hadas; Hasky, Noa; Uri-Belapolsky, Shiri; Stemmer, Salomon M; Chuderland, Dana; Shalgi, Ruth; Ben-Aharon, Irit

    2015-12-01

    Tamoxifen is a cornerstone component of adjuvant endocrine therapy for patients with hormone-receptor-positive breast cancer. Its significant adverse effects include uterine hyperplasia, polyps, and increased risk of endometrial cancer. However, the underlying molecular mechanism remains unclear. Excessive angiogenesis, a hallmark of tumorigenesis, is a result of disrupted balance between pro- and anti-angiogenic factors. VEGF is a pro-angiogenic factor shown to be elevated by tamoxifen in the uterus. Pigment epithelium-derived factor (PEDF) is a potent anti-angiogenic factor that suppresses strong pro-angiogenic factors, such as VEGF. Our aim was to investigate whether angiogenic balance plays a role in tamoxifen-induced uterine pathologies, elucidate the molecular impairment in that network, and explore potential intervention to offset the proposed imbalance elicited by tamoxifen. Using in vivo mouse models, we demonstrated that tamoxifen induced a dose-dependent shift in endogenous uterine angiogenic balance favoring VEGF over PEDF. Treatment with recombinant PEDF (rPEDF) abrogated tamoxifen-induced uterine hyperplasia and VEGF elevation, resulting in reduction of blood vessels density. Exploring the molecular mechanism revealed that tamoxifen promoted survival and malignant transformation pathways, whereas rPEDF treatment prevents these changes. Activation of survival pathways was decreased, demonstrated by reduction in AKT phosphorylation concomitant with elevation in JNK phosphorylation. Estrogen receptor-α and c-Myc oncoprotein levels were reduced. Our findings provide novel insight into the molecular mechanisms tamoxifen induces in the uterus, which may become the precursor events of subsequent endometrial hyperplasia and cancer. We demonstrate that rPEDF may serve as a useful intervention to alleviate the risk of tamoxifen-induced endometrial pathologies.

  6. Recognition of mannose 6-phosphate ligands by dystrophic rat retinal pigment epithelium

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    Tarnowski, B.; Shepherd, V.; McLaughlin, B.

    1986-05-01

    Retinal pigment epithelium (RPE) phagocytize discarded rod outer segments (ROS) during normal eye function. In the dystrophic rat, an animal model for retinitis pigmentosa in humans, ROS phagocytosis is defective. Dystrophic RPE can phagocytize particles other than ROS, suggesting that the defect may be in the RPE phagocytic recognition. They are currently investigating the recognition markers on RPE in dystrophic rats. In studies using ligand-coated latex beads, no uptake of mannose-coated beads was found in dystrophic rat RPE. They found that dystrophic RPE could specifically phagocytize phosphomannan-coated beads. Studies were begun to examine the presence and function of a phosphomannan receptor (PMR) on dystrophic RPE. ..cap alpha..-Mannosidase, isolated from D. discoideum has been shown to be an efficient ligand for the PMR in fibroblasts and macrophages. It is also recognized by the macrophage mannose receptor. Dystrophic rat RPE and retina explants were placed in culture dishes (5-7/well). /sup 125/I-Labelled ..cap alpha..-mannosidase was added to each well in the presence or absence of 10 mM mannose 6-phosphate (M6P) or yeast mannan (lmg/ml). Explants were incubated at 37/sup 0/ for 2 hr., washed and bound /sup 125/I-mannosidase quantitated. Approximately 2-3% of total counts added were bound to the RPE via a M6P-inhibitable recognition process. The binding to RPE was not blocked by mannan. No mannan or M6P-specific binding was found in retina explants. These results support the findings of specific uptake of phosphomannan-coated beads and demonstrate the presence of a specific PMR on dystrophic RPE phagocytic membranes.

  7. Pigment Epithelium-Derived Factor Inhibits Retinal Microvascular Dysfunction Induced By 12/15-Lipoxygenase-Derived Eicosanoids

    Science.gov (United States)

    Ibrahim, Ahmed S.; Tawfik, Amany M.; Hussein, Khaled A; Elshafey, Sally; Markand, Shanu; Rizk, Nasser; Duh, Elia J.; Smith, Sylvia B.; Al-Shabrawey, Mohamed

    2015-01-01

    We recently demonstrated that 12/15-lipoxygenase (LOX) derived metabolites, hydroxyeicosatetraenoic acids (HETEs), contribute to diabetic retinopathy (DR) via NADPH oxidase (NOX) and disruption of the balance in retinal levels of the vascular endothelial growth factor (VEGF) and Pigment Epithelium-Derived Factor (PEDF). Here, we test whether PEDF ameliorates retinal vascular injury induced by HETEs and the underlying mechanisms. Furthermore, we pursue the causal relationship between LOX-NOX system and regulation of PEDF expression during DR. For these purposes, we used an experimental eye model in which normal mice were injected intravitreally with 12/15HETE with/without PEDF. Thereafter, Fluorescein Angiography (FA) was used to evaluate the vascular leakage, followed by Optical coherence tomography (OCT) to assess the presence of angiogenesis. FA and OCT reported an increased vascular leakage and pre-retinal neovascularization, respectively, in response to 12-HETE that were not observed in PEDF-treated group. Moreover, PEDF significantly attenuated the increased levels of vascular cell and intercellular adhesion molecules, VCAM-1 and ICAM-1, elicited by 12-HETE injection. Accordingly, the direct relationship between HETE and PEDF has been explored through in-vitro studies using Müller cells (rMCs) and human retinal endothelial cells (HRECs). The results showed that HETEs triggered the secretion of TNF-α and IL-6, as well as activation of NFκB in rMCs and significantly increased permeability and reduced zonula occludens protein-1 (ZO-1) immunoreactivity in HRECs. All these effects were prevented in PEDF-treated cells. Furthermore, interest in PEDF regulation during DR has been expanded to include NOX system. Retinal PEDF was significantly restored in diabetic mice treated with NOX inhibitor, apocynin, or lacking NOX2 up to 80% of the control level. Collectively, our findings suggest that interfering with LOX-NOX signaling opens up a new direction for treating DR

  8. Caspase-14 Expression Impairs Retinal Pigment Epithelium Barrier Function: Potential Role in Diabetic Macular Edema

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    Selina Beasley

    2014-01-01

    Full Text Available We recently showed that caspase-14 is a novel molecule in retina with potential role in accelerated vascular cell death during diabetic retinopathy (DR. Here, we evaluated whether caspase-14 is implicated in retinal pigment epithelial cells (RPE dysfunction under hyperglycemia. The impact of high glucose (HG, 30 mM D-glucose on caspase-14 expression in human RPE (ARPE-19 cells was tested, which showed significant increase in caspase-14 expression compared with normal glucose (5 mM D-glucose + 25 mM L-glucose. We also evaluated the impact of modulating caspase-14 expression on RPE cells barrier function, phagocytosis, and activation of other caspases using ARPE-19 cells transfected with caspase-14 plasmid or caspase-14 siRNA. We used FITC-dextran flux assay and electric cell substrate impedance sensing (ECIS to test the changes in RPE cell barrier function. Similar to HG, caspase-14 expression in ARPE-19 cells increased FITC-dextran leakage through the confluent monolayer and decreased the transcellular electrical resistance (TER. These effects of HG were prevented by caspase-14 knockdown. Furthermore, caspase-14 knockdown prevented the HG-induced activation of caspase-1 and caspase-9, the only activated caspases by HG. Phagocytic activity was unaffected by caspase-14 expression. Our results suggest that caspase-14 contributes to RPE cell barrier disruption under hyperglycemic conditions and thus plays a role in the development of diabetic macular edema.

  9. Pigment epithelium derived factor suppresses expression of Sost/Sclerostin by osteocytes: implication for its role in bone matrix mineralization.

    Science.gov (United States)

    Li, Feng; Song, Na; Tombran-Tink, Joyce; Niyibizi, Christopher

    2015-06-01

    Mutations in Serpinf1 gene which encodes pigment epithelium derived factor (PEDF) lead to osteogenesis imperfecta type VI whose hallmark is defective mineralization. Mechanisms by which PEDF regulates matrix mineralization remain unknown. We examined effect of exogenous PEDF on expression of osteoblastic and osteocytic related genes and proteins in mineralizing osteoblast culture. Mineralizing human osteoblasts supplemented with exogenous PEDF for 14 days deposited 47% more mineral than cells cultured without PEDF. Analysis of selected gene expression by cells in mineralizing cultures supplemented with exogenous PEDF showed reduction in expression of Sclerostin (Sost) by 70%, matrix extracellular phosphoglycoprotein (MEPE) by 75% and dentin matrix protein (DMP-1) by 20% at day 14 of culture. Phosphate-regulating gene with homologies to endopeptidases on the X chromosome (PHEX) expression was not affected. Western blotting and immunoprecipitation showed that sclerostin and MEPE synthesis by osteocytes were reduced by 50% and 60% respectively in mineralizing osteoblasts containing exogenous PEDF. Primary osteocytes exposed to PEDF also reduced synthesis of Sost/sclerostin by 50% within 24 h. For osteoblastic genes, Bone sialoprotein (BSP) was expressed at 75% higher by day 7 in cultures containing exogenous PEDF while Col1A1 expression remained high at all-time points. Total beta-catenin was increased in mineralizing osteoblastic cells suggesting increased Wnt activity. Taken together, the data indicate that PEDF suppressed expression of factors that inhibit mineralization while enhancing those that promote mineralization. The findings also suggest that PEDF may regulate Sost expression by osteocytes leading to enhanced osteoblastic differentiation and increased matrix mineralization.

  10. Increased vascular density and vitreo-retinal membranes accompany vascularization of the pigment epithelium in the dystrophic rat retina.

    Science.gov (United States)

    Caldwell, R B; Roque, R S; Solomon, S W

    1989-09-01

    Observations of vascularization of the retinal pigment epithelium (RPE) and formation of vitreo-retinal membranes (VRMs) in Royal College of Surgeons (RCS) rats with inherited retinal dystrophy suggest that vascular proliferation occurs in this model. To test this hypothesis, we studied the progression of vascular changes in RCS and age-matched control rats using quantitative light microscope morphometry and electron microscopy. At 2 weeks, prior to photoreceptor degeneration, the dystrophic retina is comparable with the control. By 2 months, extensive degeneration of photoreceptor cells results in significant thinning of the dystrophic retina as compared with the control. Signs of vascular degeneration are evident at the electron microscope level--"ghost" vessels consisting of acellular basal lamina surrounded by amorphous electron-dense material; degenerating endothelial cells and pericytes; and abnormal deposits of extracellular matrix (ECM) material around blood vessels. Vascular degeneration is accompanied by glial changes in the form of necrotic perivascular glial processes and abnormal ECM deposits among the altered Muller cell processes. At 2-4 months in the dystrophic retina, numbers of vessel profiles in dystrophic retinas are decreased as compared with controls. However, vascular degeneration is overshadowed by the formation of numerous capillary tufts within the RPE layer, which together with retinal thinning results in increased vessel density. Between 4-12 months, the retinal thickness diminishes further, vascularization of the RPE increases, vitreo-retinal membranes are formed, and vascular density increases. In summary, following an initial period of vascular degeneration, vascularization of the RPE is accompanied by an increase in retinal vessel density and by the formation of vitreo-retinal membranes.

  11. αvβ5 Integrin/FAK/PGC-1α Pathway Confers Protective Effects on Retinal Pigment Epithelium.

    Directory of Open Access Journals (Sweden)

    Murilo F Roggia

    Full Text Available To elucidate the mechanism of the induction of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α by photoreceptor outer segments (POS and its effects on retinal pigment epithelium (RPE.PGC-1α upregulation by POS was confirmed in ARPE-19 cells and in RPE ex vivo. To elucidate the mechanism, siRNAs against β5 integrin, CD36, Mer tyrosine kinase (MerTK, and Atg5, blocking antibodies against CD36 and MerTK, and a specific inhibitor for focal adhesion kinase (FAK were used. We examined the effect of POS-induced PGC-1α upregulation on the levels of reactive oxygen species (ROS, mitochondrial biogenesis, senescence-associated β-galactosidase (SA-β-gal after H2O2 treatment, and lysosomal activity. Lysosomal activity was evaluated through transcriptional factor EB and its target genes, and the activity of cathepsin D. Lipid metabolism after POS treatment was assessed using Oil Red O and BODIPY C11. RPE phenotypes of PGC-1α-deficient mice were examined.POS-induced PGC-1α upregulation was suppressed by siRNA against β5 integrin and a FAK inhibitor. siRNAs and blocking antibodies against CD36 and MerTK enhanced the effect of POS on PGC-1α. The upregulation of PGC-1α increased the levels of mRNA for antioxidant enzymes and stimulated mitochondrial biogenesis, decreased ROS levels, and reduced SA-β-gal staining in H2O2-treated ARPE-19 cells. PGC-1α was critical for lysosomal activity and lipid metabolism after POS treatment. PGC-1α-deficient mice demonstrated an accumulation of type 2 lysosomes in RPE, thickening of Bruch's membrane, and poor choriocapillaris vasculature.The binding, but not the internalization of POS confers protective effects on RPE cells through the αvβ5 integrin/FAK/PGC-1α pathway.

  12. Ultrasound-mediated microbubble delivery of pigment epithelium-derived factor gene into retina inhibits choroidal neovascularization

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xi-yuan; LIAO Qing; PU Yi-min; TANG Yong-qiang; GONG Xiao; LI Jia; XU Yan; WANG Zhi-gang

    2009-01-01

    Background Many studies have suggested that the imbalance of angiogenic factor and anti-angiogenic factor expression contributes significantly to the development of choroidal neovascularization (CNV), and ultrasound microbubble combination system can increase the gene transfection efficiency successfully. This study was designed to investigate whether ultrasound-mediated microbubble destruction could effectively deliver therapeutic plasmid into the retina of rat, and whether gene transfer of pigment epithelium-derived factor (PEDF) could inhibit CNV.Methods Human retinal pigment epithelial cells were isolated and treated either with ultrasound or plasmid alone, or with a combination of plasmid, ultrasound and microbubbles to approach feasibility of microbubble-enhanced ultrasound enhance PEDFgene expression; For in vivo animal studies, CNV was induced by argon lasgon laser in rats. These rats were randomly assigned to five groups and were treated by infusing microbubbles attached with the naked plasmid DNA of PEDF into the vitreous of rats followed by immediate ultrasound exposure (intravitreal injection); infusing liposomes with the naked plasmid DNA of PEDF into the vitreous (lipofectamine + PEDF); infusing microbubbles attached with PEDF into the orbit of rats with ultrasound irradiation immediately (retrobular injection); infusing microbubbles attached with PEDF into the femoral vein of rats with exposed to ultrasound immediately (vein injection). The CNV rats without any treatment served as control. Rats were sacrificed and eyes were enucleated at 7, 14, and 28 days after treatment. Gene and protein expression of PEDF was detected by quantitative real-time RT-PCR, Western blotting and immunofluorescence staining, respectively. The effect of PEDF gene transfer on CNV was examined by fluorescein fundus angiography.Results In vitro cell experiments showed that microbubbles with ultrasound irradiation could significantly enhance PEDF delivery as compared with

  13. Smoke Exposure Causes Endoplasmic Reticulum Stress and Lipid Accumulation in Retinal Pigment Epithelium through Oxidative Stress and Complement Activation*

    Science.gov (United States)

    Kunchithapautham, Kannan; Atkinson, Carl; Rohrer, Bärbel

    2014-01-01

    Age-related macular degeneration (AMD) is a complex disease caused by genetic and environmental factors, including genetic variants in complement components and smoking. Smoke exposure leads to oxidative stress, complement activation, endoplasmic reticulum (ER) stress, and lipid dysregulation, which have all been proposed to be associated with AMD pathogenesis. Here we examine the effects of smoke exposure on the retinal pigment epithelium (RPE). Mice were exposed to cigarette smoke or filtered air for 6 months. RPE cells grown as stable monolayers were exposed to 5% cigarette smoke extract (CSE). Effects of smoke were determined by biochemical, molecular, and histological measures. Effects of the alternative pathway (AP) of complement and complement C3a anaphylatoxin receptor signaling were analyzed using knock-out mice or specific inhibitors. ER stress markers were elevated after smoke exposure in RPE of intact mice, which was eliminated in AP-deficient mice. To examine this relationship further, RPE monolayers were exposed to CSE. Short term smoke exposure resulted in production and release of complement C3, the generation of C3a, oxidative stress, complement activation on the cell membrane, and ER stress. Long term exposure to CSE resulted in lipid accumulation, and secretion. All measures were reversed by blocking C3a complement receptor (C3aR), alternative complement pathway signaling, and antioxidant therapy. Taken together, our results provide clear evidence that smoke exposure results in oxidative stress and complement activation via the AP, resulting in ER stress-mediated lipid accumulation, and further suggesting that oxidative stress and complement act synergistically in the pathogenesis of AMD. PMID:24711457

  14. Effect of Hypericin on Confocal Imaging of Ca2+ Signaling in Cultured Human Retinal Pigment Epithelium

    Institute of Scientific and Technical Information of China (English)

    Qianying Gao; Yannian Hui; Yusheng Wang; Lin Wang

    2001-01-01

    Purpose: To investigate the mechanism of the Ca2 + signaling in cultured human retinal pigment epithelial(RPE) cells with the protein kinase C(PKC) specific inhibitor-hypericin stimulation.Methods: Cultured human RPE cells were analyzed using the fluorescence Ca2+ dye fluo-3 AM and laser scanning confocal microscope(LSCM) after stimulation with 100nM phorbol 12-myristate 13-acetate(PMA) and (or)5 concentrations of hypericin(1, 2, 3, 4 and 5 μM).Results: The normal fluorescence in RPE cells was strong and distributed throughout the cells. The nucleus appeared to be more fluorescent than the cytoplasm. After stimulation with PMA alone or 5 concentrations of hypericin, a rapid decrease in flurescence intensity was observed. There was no obvious difference in decreased curve among 5concentrations. However, after stimulation with a 24 hr preincubation of PMA and 5 concentrations of hypericin, a further decrease was not observed.Conclusion: Fluo-3 AM appears to be a good indicator of the change in Ca2+ occurring in RPE cells and hypericin is a strong inhibitor of Ca2 + influx channel. Hypericin has potential as a therapeutic drug for proliferative vitreoretinopathy(PVR), the inhibitory effect on PVR might be caused by blocking the PKC activity and inhibiting Ca2+ influxpathway.

  15. Elevated plasma levels of pigment epithelium-derived factor correlated with inflammation and lung function in COPD patients

    Directory of Open Access Journals (Sweden)

    Li X

    2015-03-01

    Full Text Available Xiaoou Li,1–3 Tao Wang,1,2 Ting Yang,1,2 Yongchun Shen,1,2 Jing An,1,2 Lian Liu,1,2 Jiajia Dong,1,2 Lingli Guo,1,2 Diandian Li,1,2 Xue Zhang,1,2 Lei Chen,1,2 Dan Xu,1,2 Fuqiang Wen1,2 1Division of Pulmonary Diseases, State Key Laboratory of Biotherapy of China, West China Hospital, West China School of Medicine, Sichuan University, Chengdu, Sichuan, People’s Republic of China; 2Department of Respiratory Medicine, West China Hospital, West China School of Medicine, Sichuan University, Chengdu, Sichuan, People’s Republic of China; 3Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA Rationale: Pigment epithelium-derived factor (PEDF is a 50 kD small secreting glycoprotein that participates in multiple physiological and pathological processes. Recent studies have reported that PEDF plays an important role in inflammatory responses in several diseases. However, the role of PEDF in the pathogenesis of chronic obstructive pulmonary disease (COPD remains unclear.Objective: The aim of the present study is to explore the potential relationship between PEDF and COPD.Methods: We used differential proteomics – stable isotope labeling with amino acids in cell culture – to investigate protein expression profile changes in cigarette smoke extract-treated pulmonary cells and found that the neurotrophic and antiangiogenic protein PEDF was abnormally expressed. Furthermore, Western blotting was used to detect the expression of PEDF in the lung tissue of rats that were exposed to cigarette smoke. Eighty subjects between the ages of 40–90 years, including 20 healthy nonsmokers, ten smoking volunteers, and 50 COPD patients, were recruited from September 2012 until August 2013 in Sichuan Province, People’s Republic of China. We measured the plasma PEDF concentration and classic proinflammatory cytokines by multiplex enzyme-linked immunosorbent assay. In addition, we performed a spirometry examination to

  16. [Influence of cancer chemotherapy on conjunctival epithelium and goblet cells].

    Science.gov (United States)

    Wojciechowska, Katarzyna; Jesionek-Kupnicka, Dorota; Jurowski, Piotr

    2013-01-01

    Evaluation of different types of chemotherapy schemes administered in lung, breast and bowel cancer on conjunctival epithelium and goblet cells morphology. 36 patients (72 eyes) were enrolled to the study. Patients were divided into three groups depending on type of cancer and chemotherapy: group I - patients diagnosed with non- small cells lung cancer treated with PE schema (cisplatin, etoposide), group II - with breast cancer treated with FAC schema (fluorouracil, doxorubicin, cyclophosphamide), group Ill - bowel cancer treated with FU/LV schema (fluorouracil, leucovorin). Examinations were performed before chemotherapy and after Il'th, IV'th, VI'th chemotherapy cycle. Conjuntival specimen were obtained with exfoliative cytology, stained with PAS and hematoxyline. Statistically significant deterioration of conjunctival epithelium and goblet cells in all the groups in each time of examination (p<0.001) was observed. Alterations were aggravated with duration of chemotherapy. Before chemotherapy all the patients had normal epithelium and goblet cells (grade 0 or 1 according to the Nelson's scale). Conjunctival cells status gradually deteriorated and altered from the normal glandular epithelium to the squamous cells epithelium through the process of squamous metaplasia. In further chemotherapy cycles each patient (1,0 fraction) had abnormal morphology of epithelium and goblet cells (grade 2 or 3 of Nelson's scale). Chemotherapy induces squamous metaplasia of epithelium and the reduction of number of conjunctival goblet cells. This abnormalities were time dependent and increased with duration of chemotherapy and were not depended on type of chemotherapy scheme.

  17. 水蛭渗滤液对凝血酶诱导的人视网膜色素上皮细胞周期的影响%The effects of leech percolate on cell dividing cycle of human retinal pigment epithelium cells induced by thrombin.

    Institute of Scientific and Technical Information of China (English)

    郑燕林; 左玉霞; 马素红

    2008-01-01

    Objective To investigate the effects of leech percolate on cell division cycle of culturedhuman retinal pigment epithelium (hRPE)cells induced by thrombin.Exploring mechanism of leech percolateon preventing and curing PVR.Methods (1)Human retinal pigment epithelium(hRPE)cells were cultured invitro with digest culture method. (2)The selected concentrations of leech percolate (128mg/ml,64mg/ml,32mg/ml,16mg/ml and 8mg/ml)were based on the previous experiments.With or without 0.5NIHU/mlthrombin, hRPE cells were treated with leech percolate by various concentrations for 24hrs, and the effects ofcell division cycle of leech percolate were studied with Flow Cytometer (FCM). (3)With or without0.5NIHU/ml thrombin, hRPE cells were treated with 64mg/ml leech percolate at different times(6hr, 12hr,24hrand 48hr), and the effects of cell division cycle of leech percolate were treated with FCM.Results (1)Therewas a general tendency that leech percolate of the selected concentrations arrested hRPE cells on G0/G1 phaseand 64mg/mi leech percolate inhibited 77.9% hRPE cells on G0/G1 phase and made hRPE cells on S phaseless especially. (2)During the period of 6hrs and 48hrs the longer the treat time of 64mg/ml leech percolate, themore the RPE cells arrested on G0/G1 phase.Conclusion The results approve leech percolate can inhibitproliferation of human RPE cells cultured in vitro.Its mechanism may be that leech percolate could act on celldivision cycle and arrest RPE cells on G0/G1 phase to make proliferation power of hRPE cells lower.%目的 研究水蛭渗滤液对凝血酶诱导的人视网膜色素上皮细胞周期的影响,从而探讨中药水蛭用于防治PVR的作用机制.方法 (1)采用消化培养法,对人视网膜色素上皮细胞进行体外传代培养. (2)在前期实验基础上选择128mg/ml、64mg/ml、32mg/ml、16mg/ml、8mg/ml浓度的水蛭渗滤液,用流式细胞仪测定细胞周期,观察水蛭渗滤液单独或与0.5NIHU/ml凝血酶共同作用

  18. Dual regulation of adipose triglyceride lipase by pigment epithelium-derived factor: a novel mechanistic insight into progressive obesity.

    Science.gov (United States)

    Dai, Zhiyu; Qi, Weiwei; Li, Cen; Lu, Juling; Mao, Yuling; Yao, Yachao; Li, Lei; Zhang, Ting; Hong, Honghai; Li, Shuai; Zhou, Ti; Yang, Zhonghan; Yang, Xia; Gao, Guoquan; Cai, Weibin

    2013-09-05

    Both elevated plasma free fatty acids (FFA) and accumulating triglyceride in adipose tissue are observed in the process of obesity and insulin resistance. This contradictory phenomenon and its underlying mechanisms have not been thoroughly elucidated. Recent studies have demonstrated that pigment epithelium-derived factor (PEDF) contributes to elevated plasma FFA and insulin resistance in obese mice via the activation of adipose triglyceride lipase (ATGL). However, we found that PEDF downregulated adipose ATGL protein expression despite of enhancing lipolysis. Plasma PEDF and FFA were increased in associated with a progressive high-fat-diet, and those outcomes were also accompanied by fat accumulation and a reduction in adipose ATGL. Exogenous PEDF injection downregulated adipose ATGL protein expression and elevated plasma FFA, while endogenous PEDF neutralization significantly rescued the adipose ATGL reduction and also reduced plasma FFA in obese mice. PEDF reduced ATGL protein expression in a time- and dose-dependent manner in differentiated 3T3-L1 cells. Small interfering RNA-mediated PEDF knockdown and antibody-mediated PEDF blockage increased endogenous ATGL expression, and PEDF overexpression downregulated ATGL. PEDF resulted in a decreased half-life of ATGL and regulated ATGL degradation via ubiquitin-dependent proteasomal degradation pathway. PEDF stimulated lipolysis via ATGL using ATGL inhibitor bromoenol lactone, and PEDF also downregulated G0/G1 switch gene 2 (G0S2) expression, which is an endogenous inhibitor of ATGL activation. Overall, PEDF attenuated ATGL protein accumulation via proteasome-mediated degradation in adipocytes, and PEDF also promoted lipolysis by activating ATGL. Elevated PEDF may contribute to progressive obesity and insulin resistance via its dual regulation of ATGL. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. Retbindin is an extracellular riboflavin-binding protein found at the photoreceptor/retinal pigment epithelium interface.

    Science.gov (United States)

    Kelley, Ryan A; Al-Ubaidi, Muayyad R; Naash, Muna I

    2015-02-20

    Retbindin is a novel retina-specific protein of unknown function. In this study, we have used various approaches to evaluate protein expression, localization, biochemical properties, and function. We find that retbindin is secreted by the rod photoreceptors into the inter-photoreceptor matrix where it is maintained via electrostatic forces. Retbindin is predominantly localized at the interface between photoreceptors and retinal pigment epithelium microvilli, a region critical for retinal function and homeostasis. Interestingly, although it is associated with photoreceptor outer segments, retbindin's expression is not dependent on their presence. In vitro, retbindin is capable of binding riboflavin, thus implicating the protein as a metabolite carrier between the retina and the retinal pigment epithelium. Altogether, our data show that retbindin is a novel photoreceptor-specific protein with a unique localization and function. We hypothesize that retbindin is an excellent candidate for binding retinal flavins and possibly participating in their transport from the extracellular space to the photoreceptors. Further investigations are warranted to determine the exact function of retbindin in retinal homeostasis and disease.

  20. Yap and Taz regulate retinal pigment epithelial cell fate

    Science.gov (United States)

    Miesfeld, Joel B.; Gestri, Gaia; Clark, Brian S.; Flinn, Michael A.; Poole, Richard J.; Bader, Jason R.; Besharse, Joseph C.; Wilson, Stephen W.; Link, Brian A.

    2015-01-01

    The optic vesicle comprises a pool of bi-potential progenitor cells from which the retinal pigment epithelium (RPE) and neural retina fates segregate during ocular morphogenesis. Several transcription factors and signaling pathways have been shown to be important for RPE maintenance and differentiation, but an understanding of the initial fate specification and determination of this ocular cell type is lacking. We show that Yap/Taz-Tead activity is necessary and sufficient for optic vesicle progenitors to adopt RPE identity in zebrafish. A Tead-responsive transgene is expressed within the domain of the optic cup from which RPE arises, and Yap immunoreactivity localizes to the nuclei of prospective RPE cells. yap (yap1) mutants lack a subset of RPE cells and/or exhibit coloboma. Loss of RPE in yap mutants is exacerbated in combination with taz (wwtr1) mutant alleles such that, when Yap and Taz are both absent, optic vesicle progenitor cells completely lose their ability to form RPE. The mechanism of Yap-dependent RPE cell type determination is reliant on both nuclear localization of Yap and interaction with a Tead co-factor. In contrast to loss of Yap and Taz, overexpression of either protein within optic vesicle progenitors leads to ectopic pigmentation in a dosage-dependent manner. Overall, this study identifies Yap and Taz as key early regulators of RPE genesis and provides a mechanistic framework for understanding the congenital ocular defects of Sveinsson's chorioretinal atrophy and congenital retinal coloboma. PMID:26209646

  1. Threshold determinations for selective retinal pigment epithelium damage with repetitive pulsed microsecond laser systems in rabbits.

    Science.gov (United States)

    Framme, Carsten; Schuele, Georg; Roider, Johann; Kracht, Dietmar; Birngruber, Reginald; Brinkmann, Ralf

    2002-01-01

    In both clinical and animal studies, it has been shown that repetitive short laser pulses can cause selective retinal pigment epithelium damage (RPE) with sparing of photoreceptors. Our purpose was to determine the ophthalmoscopic and angiographic damage thresholds as a function of pulse durations by using different pulsed laser systems to optimize treatment modalities. Chinchilla-breed rabbits were narcotized and placed in a special holding system. Laser lesions were applied using a commercial laser slit lamp, contact lens, and irradiation with a frequency-doubled Nd:YLF laser (wave-length: 527 nm; repetition rate: 500 Hz; number of pulses: 100; pulse duration: 5 micros, 1.7 micros, 200 ns) and an argon-ion laser (514 nm, 500 Hz, 100 pulses, 5 micros and 200 ms). In all eyes, spots with different energies were placed into the regio macularis with a diameter of 102 microm (tophat profile). After treatment, fundus photography and fluorescein angiography were performed and radiant exposure for ED50 damage determined. Speckle measurements at the fiber tips were performed to determine intensity peaks in the beam profile. Using the Nd:YLF laser system, the ophthalmoscopic ED50 threshold energies were 25.4 microJ (5 micros), 32 microJ (1.7 micros), and 30 microJ (200 ns). The angiographic ED50 thresholds were 13.4 microJ (5 micros), 9.2 microJ (1.7 micros), and 6.7 microJ (200 ns). With the argon laser, the angiographic threshold for 5 micros pulses was 5.5 microJ. The ophthalmoscopic threshold could not be determined because of a lack of power; however, it was > 12 microJ. For 200 ms, the ED50 radiant exposures were 20.4 mW ophthalmoscopically and 19.2 mW angiographically. Speckle factors were found to be 1.225 for the Nd:YLF and 3.180 for the argon laser. Thus, the maximal ED50 -threshold radiant exposures for the Nd:YLF were calculated to be 362 mJ/cM2 (5 micros), 478 mJ/cm2 (1.7 micros), and 438 mJ/cm2 (200 ns) ophthalmoscopically. Angiographically, the thresholds

  2. Multifocal central serous chorioretinopathy with photoreceptor-retinal pigment epithelium diastasis in heritable pulmonary arterial hypertension

    DEFF Research Database (Denmark)

    Li, Xiao Qiang; Pryds, Anders; Carlsen, Jørn;

    2015-01-01

    with clinical examination, enhanced depth optical coherence tomography, fluorescein and indocyanine green angiography, and fundus photography. RESULTS: At presentation, atypical central serous chorioretinopathy with multiple retinal pigment epithelial detachments, a thick subfoveal choroid, and dilated...

  3. Genomic regulation of senescence and innate immunity signaling in the retinal pigment epithelium.

    Science.gov (United States)

    Chaum, Edward; Winborn, Christina S; Bhattacharya, Sujoy

    2015-06-01

    The tumor suppressor p53 is a major regulator of genes important for cell cycle arrest, senescence, apoptosis, and innate immunity, and has recently been implicated in retinal aging. In this study we sought to identify the genetic networks that regulate p53 function in the retina using quantitative trait locus (QTL) analysis. First we examined age-associated changes in the activation and expression levels of p53; known p53 target proteins and markers of innate immune system activation in primary retinal pigment epithelial (RPE) cells that were harvested from young and aged human donors. We observed increased expression of p53, activated caspase-1, CDKN1A, CDKN2A (p16INK4a), TLR4, and IFNα in aged primary RPE cell lines. We used the Hamilton Eye Institute (HEI) retinal dataset ( www.genenetwork.org ) to identify genomic loci that modulate expression of genes in the p53 pathway in recombinant inbred BXD mouse strains using a QTL systems biology-based approach. We identified a significant trans-QTL on chromosome 1 (region 172-177 Mb) that regulates the expression of Cdkn1a. Many of the genes in this QTL locus are involved in innate immune responses, including Fc receptors, interferon-inducible family genes, and formin 2. Importantly, we found an age-related increase in FCGR3A and FMN2 and a decrease in IFI16 levels in RPE cultures. There is a complex multigenic innate immunity locus that controls expression of genes in the p53 pathway in the RPE, which may play an important role in modulating age-related changes in the retina.

  4. DJ-1-dependent regulation of oxidative stress in the retinal pigment epithelium (RPE.

    Directory of Open Access Journals (Sweden)

    Karen G Shadrach

    Full Text Available BACKGROUND: DJ-1 is found in many tissues, including the brain, where it has been extensively studied due to its association with Parkinson's disease. DJ-1 functions as a redox-sensitive molecular chaperone and transcription regulator that robustly protects cells from oxidative stress. METHODOLOGY: Retinal pigment epithelial (RPE cultures were treated with H2O2 for various times followed by biochemical and immunohistological analysis. Cells were transfected with adenoviruses carrying the full-length human DJ-1 cDNA and a mutant construct, which has the cysteine residues at amino acid 46, 53 and 106 mutated to serine (C to S prior to stress experiments. DJ-1 localization, levels of expression and reactive oxygen species (ROS generation were also analyzed in cells expressing exogenous DJ-1 under baseline and oxidative stress conditions. The presence of DJ-1 and oxidized DJ-1 was evaluated in human RPE total lysates. The distribution of DJ-1 was assessed in AMD and non-AMD cryosectionss and in isolated human Bruch's membrane (BM/choroid from AMD eyes. PRINCIPAL FINDINGS: DJ-1 in RPE cells under baseline conditions, displays a diffuse cytoplasmic and nuclear staining. After oxidative challenge, more DJ-1 was associated with mitochondria. Increasing concentrations of H2O2 resulted in a dose-dependent increase in DJ-1. Overexpression of DJ-1 but not the C to S mutant prior to exposure to oxidative stress led to significant decrease in the generation of ROS. DJ-1 and oxDJ-1 intensity of immunoreactivity was significantly higher in the RPE lysates from AMD eyes. More DJ-1 was localized to RPE cells from AMD donors with geographic atrophy and DJ-1 was also present in isolated human BM/choroid from AMD eyes. CONCLUSIONS/SIGNIFICANCE: DJ-1 regulates RPE responses to oxidative stress. Most importantly, increased DJ-1 expression prior to oxidative stress leads to decreased generation of ROS, which will be relevant for future studies of AMD since oxidative

  5. Benzo(a)pyrene and X-rays induce reversions of the pink-eyed unstable mutation in the retinal pigment epithelium of mice.

    Science.gov (United States)

    Bishop, A J; Kosaras, B; Sidman, R L; Schiestl, R H

    2000-12-20

    The pink-eyed unstable (p(un)) mutation is the result of a 70kb tandem duplication within the murine p gene. Homologous deletion/recombination of the locus to wild-type occurs spontaneously in embryos and results in pigmented spots in the fur and eye that persist for life. Such deletion events are also inducible by a variety of DNA damaging agents, as we have observed previously with the fur spot assay. Here, we describe the use of the retinal pigment epithelium (RPE) of the eye to detect reversion events induced with two differently acting agents. Benzo(a)pyrene (B(a)P) induces a high frequency, and X-ray exposure a more modest increase, of p(un) reversion in both the fur and the eye. The eye-spot assay requires fewer mice for significant results than the fur spot assay. Previous work had elucidated the cell proliferation pattern in the RPE and a position effect variegation phenotype in the pattern of p(un) reversions, which we have confirmed. Acute exposure to B(a)P or X-rays resulted in an increased frequency of reversion events. The majority of the spontaneous reversions lie toward the periphery of the RPE whereas induced events are found more centrally, closer to the optic nerve head. The induced distribution corresponds to the major sites of cell proliferation in the RPE at the time of exposure, and further advocates the proposal that dividing cells are at highest risk to develop deletions.

  6. Automatic detection of subretinal fluid and sub-retinal pigment epithelium fluid in optical coherence tomography images.

    Science.gov (United States)

    Ding, Weiguang; Young, Mei; Bourgault, Serge; Lee, Sieun; Albiani, David A; Kirker, Andrew W; Forooghian, Farzin; Sarunic, Marinko V; Merkur, Andrew B; Beg, Mirza Faisal

    2013-01-01

    Age-related macular degeneration (AMD) is the leading cause of blindness in developed countries. Subretinal fluid (SRF) and sub-retinal pigment epithelium (sub-RPE) fluid are signs of AMD and can be detected in optical coherence tomography images. However, manual detection and segmentation of SRFs and sub-RPE fluids are laborious and time consuming. In this paper, a novel pipeline is proposed for automatic detection of SRFs and sub-RPE fluids. First, top and bottom layers of retina are segmented using a graph cut method. Then, a Split Bregman-based segmentation method is used to segment dark regions between layers. These segmented regions are considered as potential fluid candidates, on which a set of features are generated. After that, a random forest classifier is trained to distinguish between the true fluid regions from the falsely detected fluid regions. This method shows reasonable performance in a leave-one-out evaluation using a dataset from 21 patients.

  7. [Combined hamartoma of the retina and retinal pigment epithelium. Anti-VEGF treatment of the associated choroidal neovascular membranes].

    Science.gov (United States)

    Echevarría, L; Villena, O; Nievas, T; Bellido, R

    2015-02-01

    A 58 year-old female was diagnosed with a juxtapapillary combined hamartoma of the retina and retinal pigment epithelium (CHR-RPE) in her left eye 14 years ago. Her visual acuity in that eye was 20/20. Recently, she came to our department with a sudden visual loss and metamorphopsis in her left eye. After performing funduscopy, angiography and OCT, she was diagnosed with choroidal neovascular membrane (CNVM) at lesion border, and started on antiangiogenic therapy. CHR-RPE, despite being a benign condition, may become complicated with severe visual impairment. Antiangiogenic therapy provides a good alternative to photodynamic therapy or laser photocoagulation for treatment of CNVM, avoiding adding iatrogenesis from these treatment to the complications associated with this pathology. Copyright © 2014 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  8. Noninvasive two-photon microscopy imaging of mouse retina and retinal pigment epithelium through the pupil of the eye.

    Science.gov (United States)

    Palczewska, Grazyna; Dong, Zhiqian; Golczak, Marcin; Hunter, Jennifer J; Williams, David R; Alexander, Nathan S; Palczewski, Krzysztof

    2014-07-01

    Two-photon excitation microscopy can image retinal molecular processes in vivo. Intrinsically fluorescent retinyl esters in subcellular structures called retinosomes are an integral part of the visual chromophore regeneration pathway. Fluorescent condensation products of all-trans-retinal accumulate in the eye with age and are also associated with age-related macular degeneration (AMD). Here, we report repetitive, dynamic imaging of these compounds in live mice through the pupil of the eye. By leveraging advanced adaptive optics, we developed a data acquisition algorithm that permitted the identification of retinosomes and condensation products in the retinal pigment epithelium by their characteristic localization, spectral properties and absence in genetically modified or drug-treated mice. This imaging approach has the potential to detect early molecular changes in retinoid metabolism that trigger light- and AMD-induced retinal defects and to assess the effectiveness of treatments for these conditions.

  9. Activation of Rap1 inhibits NADPH oxidase-dependent ROS generation in retinal pigment epithelium and reduces choroidal neovascularization

    Science.gov (United States)

    Wang, Haibo; Jiang, Yanchao; Shi, Dallas; Quilliam, Lawrence A.; Chrzanowska-Wodnicka, Magdalena; Wittchen, Erika S.; Li, Dean Y.; Hartnett, M. Elizabeth

    2014-01-01

    Activation of Rap1 GTPase can improve the integrity of the barrier of the retina pigment epithelium (RPE) and reduce choroidal neovascularization (CNV). Inhibition of NADPH oxidase activation also reduces CNV. We hypothesize that Rap1 inhibits NADPH oxidase-generated ROS and thereby reduces CNV formation. Using a murine model of laser-induced CNV, we determined that reduced Rap1 activity in RPE/choroid occurred with CNV formation and that activation of Rap1 by 2′-O-Me-cAMP (8CPT)-reduced laser-induced CNV via inhibiting NADPH oxidase-generated ROS. In RPE, inhibition of Rap1 by Rap1 GTPase-activating protein (Rap1GAP) increased ROS generation, whereas activation of Rap1 by 8CPT reduced ROS by interfering with the assembly of NADPH oxidase membrane subunit p22phox with NOX4 or cytoplasmic subunit p47phox. Activation of NADPH oxidase with Rap1GAP reduced RPE barrier integrity via cadherin phosphorylation and facilitated choroidal EC migration across the RPE monolayer. Rap1GAP-induced ROS generation was inhibited by active Rap1a, but not Rap1b, and activation of Rap1a by 8CPT in Rap1b−/− mice reduced laser-induced CNV, in correlation with decreased ROS generation in RPE/choroid. These findings provide evidence that active Rap1 reduces CNV by interfering with the assembly of NADPH oxidase subunits and increasing the integrity of the RPE barrier.—Wang, H., Jiang, Y., Shi, D., Quilliam, L. A., Chrzanowska-Wodnicka, M., Wittchen, E. S., Li, D. Y., Hartnett, M. E. Activation of Rap1 inhibits NADPH oxidase-dependent ROS generation in retinal pigment epithelium and reduces choroidal neovascularization. PMID:24043260

  10. Role of pigment epithelium-derived factor on proliferation and migration of choroidal capillary endothelium induced by vascular endothelial growth factor in vitro

    Institute of Scientific and Technical Information of China (English)

    WANG Feng-hua; SUN Xiao-dong; ZHANG Xi; XU Xun; ZHU Qi; HUANG Jian-nan; FAN Ying; GU Qing; LIU Hai-yang

    2007-01-01

    Background Pigment epithelium-derived factor (PEDF) is expressed in several normal organs and identified as an inhibitor of neovascularization. In the present study, we investigated the effect of PEDF in an in vitro model of ocular choroidal neovascularization.Methods Microdissection was used to isolate the human choroidal endothelial cells (CECs), followed by the use of superparamagnetic beads (Dynabeads) coated with the CD31 antibody, which selectively binds to the endothelial cell surface. The mitogenic and motogenic effects of vascular endothelial growth factor (VEGF) on cultured choroidal capillary endothelial cells were examined in the presence or absence of PEDF (1, 10, 100, and 1000 ng/ml) using cell counts and migration assays.Results Cells bound to the beads were isolated using a magnetic particle concentrator and they were successfully cultured and characterized to be endothelial cells that possessed greater than 95% immunoreactivity to von Willebrand factor. PEDF suppressed the proliferation and migration of VEGF-induced choroidal capillary endothelial cells. However,the concentration of PEDF which we used has little effect on normal CECs.Conclusions PEDF played an important role on the growth and migration of VEGF-stimulated choroidal endothelial cell.These findings suggest that PEDF may be an effective approach to the treatment of choroidal neovascular disorders.

  11. Effect of curcumin on aging retinal pigment epithelial cells

    Directory of Open Access Journals (Sweden)

    Zhu W

    2015-09-01

    Full Text Available Wei Zhu,1,* Yan Wu,2,* Yi-Fang Meng,1 Jin-Yu Wang,1 Ming Xu,1 Jian-Jun Tao,1 Jiong Lu1 1Department of Ophthalmology, Changshu No 2 People’s Hospital, Changshu, 2Department of Ophthalmology, The First People’s Hospital of Kunshan Affiliated with Jiangsu University, Suzhou, People’s Republic of China *These authors contributed equally to this work Abstract: Age-related macular degeneration (AMD is now one of the leading causes of blindness in the elderly population. The antioxidative effects of curcumin on aging retinal pigment epithelial (RPE cells are still unclear. We conducted an in vitro study to investigate the effects of curcumin on aging RPE cells. A pulsed H2O2 exposure aging model was adopted. Aging RPE cells were treated with curcumin 20 µM, 40 µM, and 80 µM. Apoptosis of RPE cells was analyzed by flow cytometry. The intracellular reactive oxygen species concentration was detected using a specific probe and apoptosis-associated proteins were detected by Western blot. Expression of oxidative biomarkers, including superoxide dismutase, maleic dialdehyde, and glutathione, was detected commercially available assay kits. Compared with normal cells, lower cell viability, higher apoptosis rates, and more severe oxidation status were identified in the aging RPE cell model. Curcumin improved cell viability and decreased apoptosis and oxidative stress. Further, curcumin had a significant influence on expression of apoptosis-associated proteins and oxidative stress biomarkers. In conclusion, treatment with curcumin was able to regulate proliferation, oxidative stress, and apoptosis in aging RPE cells. Accordingly, application of curcumin may be a novel strategy to protect against age-related change in AMD. Keywords: curcumin, retinal pigment epithelium, apoptosis, age-related macular degeneration

  12. Coelomic epithelium-derived cells in visceral morphogenesis.

    Science.gov (United States)

    Ariza, Laura; Carmona, Rita; Cañete, Ana; Cano, Elena; Muñoz-Chápuli, Ramón

    2016-03-01

    Coelomic cavities of vertebrates are lined by a mesothelium which develops from the lateral plate mesoderm. During development, the coelomic epithelium is a highly active cell layer, which locally is able to supply mesenchymal cells that contribute to the mesodermal elements of many organs and provide signals which are necessary for their development. The relevance of this process of mesenchymal cell supply to the developing organs is becoming clearer because genetic lineage tracing techniques have been developed in recent years. Body wall, heart, liver, lungs, gonads, and gastrointestinal tract are populated by cells derived from the coelomic epithelium which contribute to their connective and vascular tissues, and sometimes to specialized cell types such as the stellate cells of the liver, the Cajal interstitial cells of the gut or the Sertoli cells of the testicle. In this review we collect information about the contribution of coelomic epithelium derived cells to visceral development, their developmental fates and signaling functions. The common features displayed by all these processes suggest that the epithelial-mesenchymal transition of the embryonic coelomic epithelium is an underestimated but key event of vertebrate development, and probably it is shared by all the coelomate metazoans.

  13. Ontogeny of electrically excitable cells in cultured olfactory epithelium.

    OpenAIRE

    Schubert, D; Stallcup, W.; LaCorbiere, M; Kidokoro, Y; Orgel, L

    1985-01-01

    A primary system has been developed in which it is possible to study the production of electrically excitable neuron-like cells from a precursor population of olfactory epithelial cells. Rat nasal epithelium was dissociated and placed in culture. The initial surviving cells are flat and ciliated and contain glial fibrillary acidic protein (GFAP). After 3-5 days electrically excitable cells appear that contain neuron-specific enolase but not GFAP. These round cells originate by means of the di...

  14. Yap and Taz regulate retinal pigment epithelial cell fate.

    Science.gov (United States)

    Miesfeld, Joel B; Gestri, Gaia; Clark, Brian S; Flinn, Michael A; Poole, Richard J; Bader, Jason R; Besharse, Joseph C; Wilson, Stephen W; Link, Brian A

    2015-09-01

    The optic vesicle comprises a pool of bi-potential progenitor cells from which the retinal pigment epithelium (RPE) and neural retina fates segregate during ocular morphogenesis. Several transcription factors and signaling pathways have been shown to be important for RPE maintenance and differentiation, but an understanding of the initial fate specification and determination of this ocular cell type is lacking. We show that Yap/Taz-Tead activity is necessary and sufficient for optic vesicle progenitors to adopt RPE identity in zebrafish. A Tead-responsive transgene is expressed within the domain of the optic cup from which RPE arises, and Yap immunoreactivity localizes to the nuclei of prospective RPE cells. yap (yap1) mutants lack a subset of RPE cells and/or exhibit coloboma. Loss of RPE in yap mutants is exacerbated in combination with taz (wwtr1) mutant alleles such that, when Yap and Taz are both absent, optic vesicle progenitor cells completely lose their ability to form RPE. The mechanism of Yap-dependent RPE cell type determination is reliant on both nuclear localization of Yap and interaction with a Tead co-factor. In contrast to loss of Yap and Taz, overexpression of either protein within optic vesicle progenitors leads to ectopic pigmentation in a dosage-dependent manner. Overall, this study identifies Yap and Taz as key early regulators of RPE genesis and provides a mechanistic framework for understanding the congenital ocular defects of Sveinsson's chorioretinal atrophy and congenital retinal coloboma. © 2015. Published by The Company of Biologists Ltd.

  15. Lymphoid cells in chicken intestinal epithelium

    DEFF Research Database (Denmark)

    Bjerregaard, P

    1975-01-01

    The intraepithelial lymphoid cells of chicken small intestine were studied by light microscopy using 1 mu Epon sections, and by electron microscopy. Three cell types were found: small lymphocytes, large lymphoid cells, and granular cells. These cells correspond to the theliolymphocytes and globule...

  16. Lymphoid cells in chicken intestinal epithelium

    DEFF Research Database (Denmark)

    Bjerregaard, P

    1975-01-01

    The intraepithelial lymphoid cells of chicken small intestine were studied by light microscopy using 1 mu Epon sections, and by electron microscopy. Three cell types were found: small lymphocytes, large lymphoid cells, and granular cells. These cells correspond to the theliolymphocytes and globule...

  17. Transport of protons and lactate in cultured human fetal retinal pigment epithelial cells

    DEFF Research Database (Denmark)

    Hamann, Steffen; Cour, Morten la; Ming Lui, Ge

    2000-01-01

    Electron microscopy, intracellular pH, monocarboxylate transport, pigment epithelium of eye, proton-lactate cotransport, retinal metabolism, sodium/proton exchange......Electron microscopy, intracellular pH, monocarboxylate transport, pigment epithelium of eye, proton-lactate cotransport, retinal metabolism, sodium/proton exchange...

  18. A Possible Role of Acrolein in Diabetic Retinopathy: Involvement of a VEGF/TGFβ Signaling Pathway of the Retinal Pigment Epithelium in Hyperglycemia

    Science.gov (United States)

    Grigsby, Jeffery; Betts, Brandi; Vidro-Kotchan, Eileen; Culbert, Richard; Tsin, Andrew

    2015-01-01

    Purpose Acrolein has been implicated in retinal pigment epithelium (RPE) cell death, and has been associated with diabetic retinopathy. Our purpose was to investigate the potential effect of high glucose in influencing acrolein-mediated RPE cytokine production and cell death. We investigated the influence of the acrolein effect on ARPE-19 cells in high glucose conditions and quantified the release of transforming growth factor β (TGFβ1 and 2) and vascular endothelial growth factor (VEGF). We assessed the ability of N-benzylhydroxylamine(NBHA) as well as TGFβ pathway inhibitors SIS3 and SB431542 to prevent this effect of acrolein on ARPE-19 cells. Materials and methods Confluent ARPE-19 cells were treated with acrolein and/or NBHA in both 5.5 and 18.8 mM glucose conditions. Cells were also pretreated with SIS3, a specific inhibitor of the SMAD3 pathway, and SB431542, a specific inhibitor of TGFβ signaling pathway, before treating them with acrolein. Viable cells were counted and ELISAs were performed to measure the cytokines TGFβ1 and 2, and VEGF released into the conditioned media. Results In ARPE-19 cells exposed to acrolein and hyperglycemia there was reduced cell viability and an increase in the cell media of VEGF, TGFβ1, and TGFβ2, which was reversed by NBHA. Acrolein/hyperglycemia-induced cell viability reduction and cytokine overproduction was also reduced by TGFβ pathway blockade. Conclusions We conclude that the effect of acrolein on the reduction of viability and VEGF increase by ARPE-19 cells in hyperglycemic media is conducted through the TGFβ signaling pathway. Our results suggest that benefits of sequestering acrolein by NBHA and the blockage of the TGFβ pathway by SB431542 and SIS3 offer suggestions as to potential useful pharmacological drug candidates for the prevention of diabetes-induced complications in the eye. PMID:22906079

  19. Epiretinal membrane surgery for combined hamartoma of the retina and retinal pigment epithelium: role of multimodal analysis

    Directory of Open Access Journals (Sweden)

    Bruè C

    2013-01-01

    Full Text Available Claudia Bruè, Andrea Saitta, Michele Nicolai, Cesare Mariotti, Alfonso GiovanniniOphthalmology, Department of Neuroscience, Marche Polytechnic University, Ancona, ItalyBackground: The purpose of this study was to evaluate the role of spectral domain optical coherence tomography (SD-OCT, MP-1 microperimetry, and fundus autofluorescence imaging for planning surgical procedures in combined hamartomas of the retina and retinal pigment epithelium (CHR-RPE and following epiretinal membrane removal.Methods: In an interventional retrospective case series, six consecutive subjects with CHR-RPE underwent vitrectomy and epiretinal membrane peeling, with 4 years of follow-up. Each underwent complete ophthalmic examination, including best corrected visual acuity, fundus examination, fundus fluorescein angiography, SD-OCT, MP-1, and fundus autofluorescence at one, 6, 12, and 48 months.Results: Six eyes from six subjects with CHR-RPE were studied (mean age 31 ± 14 years. All patients were phakic and five were male (83.3%. Lesions were unilateral, ie, three macular, two juxtapapillary and macular, and one pericentral. Preoperative best corrected visual acuity was 0.3 ± 0.08 Snellen, with significant improvement to 0.9 ± 0.17 Snellen (P = 0.001 at 4 years of follow-up. Mean retinal sensitivity within the central 20° field improved from 16.6 ± 1.84 dB to 18.8 ± 0.96 dB (P = 0.07. There was also a statistically significant reduction in the visual defect (P = 0.04. SD-OCT demonstrated that the epiretinal membranes were completely removed in all but one patient, with significantly decreased macular edema on follow-up at one, 6, 12, and 48 months (P = 0.001. A positive correlation was shown between preoperative macular sensitivity and postoperative best corrected visual acuity. Fundus autofluorescence demonstrated a block in background autofluorescence at the site of the lesion, and hyperautofluorescsence at the edematous retina overlain by the epiretinal

  20. Oxalomalate reduces expression and secretion of vascular endothelial growth factor in the retinal pigment epithelium and inhibits angiogenesis: Implications for age-related macular degeneration

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    Sung Hwan Kim

    2016-12-01

    Full Text Available Clinical and experimental observations indicate a critical role for vascular endothelial growth factor (VEGF, secreted by the retinal pigment epithelium (RPE, in pathological angiogenesis and the development of choroidal neovascularization (CNV in age-related macular degeneration (AMD. RPE-mediated VEGF expression, leading to angiogenesis, is a major signaling mechanism underlying ocular neovascular disease. Inhibiting this signaling pathway with a therapeutic molecule is a promising anti-angiogenic strategy to treat this disease with potentially fewer side effects. Oxalomalate (OMA is a competitive inhibitor of NADP+-dependent isocitrate dehydrogenase (IDH, which plays an important role in cellular signaling pathways regulated by reactive oxygen species (ROS. Here, we have investigated the inhibitory effect of OMA on the expression of VEGF, and the associated underlying mechanism of action, using in vitro and in vivo RPE cell models of AMD. We found that OMA reduced the expression and secretion of VEGF in RPE cells, and consequently inhibited CNV formation. This function of OMA was linked to its capacity to activate the pVHL-mediated HIF-1α degradation in these cells, partly via a ROS-dependent ATM signaling axis, through inhibition of IDH enzymes. These findings reveal a novel role for OMA in inhibiting RPE-derived VEGF expression and angiogenesis, and suggest unique therapeutic strategies for treating pathological angiogenesis and AMD development.

  1. MERTK signaling in the retinal pigment epithelium regulates the tyrosine phosphorylation of GDP dissociation inhibitor alpha from the GDI/CHM family of RAB GTPase effectors.

    Science.gov (United States)

    Shelby, Shameka J; Feathers, Kecia L; Ganios, Anna M; Jia, Lin; Miller, Jason M; Thompson, Debra A

    2015-11-01

    Photoreceptor outer segments (OS) in the vertebrate retina undergo a process of continual renewal involving shedding of disc membranes that are cleared by phagocytic uptake into the retinal pigment epithelium (RPE). In dystrophic Royal College of Surgeons (RCS) rats, OS phagocytosis is blocked by a mutation in the gene encoding the receptor tyrosine kinase MERTK. To identify proteins tyrosine-phosphorylated downstream of MERTK in the RPE, MALDI-mass spectrometry with peptide-mass fingerprinting was used in comparative studies of RCS congenic and dystrophic rats. At times corresponding to peak phagocytic activity, the RAB GTPase effector GDP dissociation inhibitor alpha (GDI1) was found to undergo tyrosine phosphorylation only in congenic rats. In cryosections of native RPE/choroid, GDI1 colocalized with MERTK and the intracellular tyrosine-kinase SRC. In cultured RPE-J cells, and in transfected heterologous cells, MERTK stimulated SRC-mediated tyrosine phosphorylation of GDI1. In OS-fed RPE-J cells, GDI1 colocalized with MERTK and SRC on apparent phagosomes located near the apical membrane. In addition, both GDI1 and RAB5, a regulator of vesicular transport, colocalized with ingested OS. Taken together, these findings identify a novel role of MERTK signaling in membrane trafficking in the RPE that is likely to subserve mechanisms of phagosome formation.

  2. TRPM5-expressing microvillous cells in the main olfactory epithelium

    Directory of Open Access Journals (Sweden)

    Liman Emily R

    2008-11-01

    Full Text Available Abstract Background The main olfactory epithelium (MOE in the nasal cavity detects a variety of air borne molecules that provide information regarding the presence of food, predators and other relevant social and environmental factors. Within the epithelium are ciliated sensory neurons, supporting cells, basal cells and microvillous cells, each of which is distinct in morphology and function. Arguably, the least understood, are the microvillous cells, a population of cells that are small in number and whose function is not known. We previously found that in a mouse strain in which the TRPM5 promoter drives expression of the green fluorescent protein (GFP, a population of ciliated olfactory sensory neurons (OSNs, as well as a population of cells displaying microvilli-like structures is labeled. Here we examined the morphology and immunocytochemical properties of these microvillous-like cells using immunocytochemical methods. Results We show that the GFP-positive microvillous cells were morphologically diversified and scattered throughout the entire MOE. These cells immunoreacted to an antibody against TRPM5, confirming the expression of this ion channel in these cells. In addition, they showed a Ca2+-activated non-selective cation current in electrophysiological recordings. They did not immunoreact to antibodies that label cell markers and elements of the transduction pathways from olfactory sensory neurons and solitary chemosensory cells of the nasal cavity. Further, the TRPM5-expressing cells did not display axon-like processes and were not labeled with a neuronal marker nor did trigeminal peptidergic nerve fibers innervate these cells. Conclusion We provide morphological and immunocytochemical characterization of the TRPM5-expressing microvillous cells in the main olfactory epithelium. Our data demonstrate that these cells are non-neuronal and in terms of chemosensory transduction do not resemble the TRPM5-expressing olfactory sensory neurons

  3. Growth of cultured porcine retinal pigment epithelial cells

    DEFF Research Database (Denmark)

    Wiencke, A.K.; Kiilgaard, Jens Folke; Nicolini, Jair;

    2003-01-01

    To establish and characterize cultures of porcine retinal pigment epithelial (pRPE) cells in order to produce confluent monolayers of cells for transplantation.......To establish and characterize cultures of porcine retinal pigment epithelial (pRPE) cells in order to produce confluent monolayers of cells for transplantation....

  4. Progressive atrophy of retinal pigment epithelium after trypan-blue-assisted ILM peeling for macular hole surgery

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    Sachin Jain

    2013-01-01

    Full Text Available We report a case of progressive atrophy of the retinal pigment epithelium (RPE after trypan-blue-assisted peeling of internal limiting membrane (ILM for macular hole surgery. A 68-year-old Caucasian female underwent a 20-g pars plana vitrectomy for a chronic stage-3 macular hole. The ILM was stained with 0.06% trypan blue (VisionBlue™, DORC Netherlands for 2 min after fluid air exchange. Dye was reapplied for another 2 min due to poor staining. The ILM was completely removed around the macular hole with forceps. RPE atrophy was noticed at the edge of the hole 1 month after surgery. It progressively increased in intensity and enlarged over 2 years. Her final visual acuity was counting fingers, significantly worse compared to her presenting visual acuity of 20/200. Progressive atrophy of RPE in our patient was most likely due to the toxicity of trypan blue. Reapplication of the dye may increase the likelihood of toxicity.

  5. Peroxidation stimulated by lipid hydroperoxides on bovine retinal pigment epithelium mitochondria: effect of cellular retinol-binding protein.

    Science.gov (United States)

    Terrasa, Ana M; Guajardo, Margarita H; Catalá, Angel

    2003-07-01

    This study analyzes the effect of cellular retinol-binding protein (CRBP), partially purified from retinal pigment epithelium (RPE) cytosol, on the non-enzymatic lipid peroxidation induced by fatty acid hydroperoxides of mitochondrial membranes isolated from bovine RPE. The effect of different amounts (50, 75 and 100 nmol) of linoleic acid hydroperoxide (LHP), arachidonic acid hydroperoxide (AHP) and docosahexaenoic acid hydroperoxide (DHP) on the lipid peroxidation of RPE mitochondria was studied; RPE mitochondria deprived of exogenously added hydroperoxide was utilized as control. The process was measured simultaneously by determining chemiluminescence as well as polyunsaturated fatty acid (PUFA) degradation of total lipids isolated from RPE mitochondria. The addition of hydroperoxides to RPE mitochondria produces a marked increase in light emission that was hydroperoxide concentration dependent. The highest value of activation was produced by LHP. The major difference in the fatty acid composition of total lipids isolated from native and peroxidized RPE mitochondria incubated with and without hydroperoxides was found in the docosahexaenoic acid content, this decreased 40.90+/-3.01% in the peroxidized group compared to native RPE mitochondria. The decrease was significantly high: 86.32+/-2.57% when the lipid peroxidation was stimulated by 100 nmol of LHP. Inhibition of lipid peroxidation (decrease of chemiluminescence) was observed with the addition of increasing amounts (100-600 microg) of CRBP to RPE mitochondria. The inhibitory effect reaches the highest values in the presence of LHP.

  6. Pigment epithelium-derived factor enhances tumor response to radiation through vasculature normalization in allografted lung cancer in mice.

    Science.gov (United States)

    Xu, Z; Dong, Y; Peng, F; Yu, Z; Zuo, Y; Dai, Z; Chen, Y; Wang, J; Hu, X; Zhou, Q; Ma, H; Bao, Y; Gao, G; Chen, M

    2015-03-01

    This study aimed to explore the potential therapeutic effects of the combination of pigment epithelium-derived factor (PEDF) and radiation on lung cancer. The Lewis lung cancer (LLC) allografts in nude mice were treated with radiation, PEDF and PEDF combined with radiation. The morphologic changes of tumor vasculature and the hypoxic fraction of tumor tissues were evaluated. Significant inhibition of tumor growth was observed when radiation was applied between the 3rd and 7th day (the vasculature normalization window) after the initiation of PEDF treatment. During the vasculature normalization window, the tumor blood vessels in PEDF-treated mice were less tortuous and more uniform than those in the LLC allograft tumor treated with phosphate-buffered saline. Meanwhile, the thickness of the basement membrane was remarkably reduced and pericyte coverage was significantly increased with the PEDF treatment. We also found that tumor hypoxic fraction decreased during the 3rd to the 7th day after PEDF treatment, suggesting improved intratumoral oxygenation. Taken together, our results show that PEDF improved the effects of radiation therapy on LLC allografts by inducing a vascular normalization window from the 3rd to the 7th day after PEDF treatment. Our findings provide a basis for treating lung cancer with the combination of PEDF and radiation.

  7. Alzheimer's disease: Elevated pigment epithelium-derived factor in the cerebrospinal fluid is mostly of systemic origin.

    Science.gov (United States)

    Lang, Veronika; Zille, Marietta; Infante-Duarte, Carmen; Jarius, Sven; Jahn, Holger; Paul, Friedemann; Ruprecht, Klemens; Pina, Ana Luisa

    2017-04-15

    Pigment-epithelium derived factor (PEDF) is a neurotrophic factor with neuroprotective, anti-tumorigenic, and anti-angiogenic effects. Elevated levels of PEDF have previously been proposed as a cerebrospinal fluid (CSF) biomarker for Alzheimer's disease. However, the origin of PEDF in CSF, i.e. whether it is derived from the brain or from the systemic circulation, and the specificity of this finding hitherto remained unclear. Here, we analyzed levels of PEDF in paired CSF and serum samples by ELISA in patients with Alzheimer's disease (AD, n=12), frontotemporal dementia (FTD, n=6), vascular dementia (n=4), bacterial meningitis (n=8), multiple sclerosis (n=32), pseudotumor cerebri (n=36), and diverse non-inflammatory neurological diseases (n=19). We established CSF/serum quotient diagrams to determine the fraction of intrathecally synthesized PEDF in CSF. We found that PEDF is significantly increased in CSF of patients with AD, FTD, and bacterial meningitis. Remarkably, PEDF concentrations were also significantly elevated in serum of patients with AD. CSF/serum quotient diagrams demonstrated that elevated PEDF concentrations in CSF of patients with AD are mostly due to elevated PEDF concentrations in serum. These findings underscore the importance of relating concentrations of proteins in CSF to their respective concentrations in serum to avoid erroneous interpretations of increased protein concentrations in lumbar CSF.

  8. Pigment Epithelium-Derived Factor Reduces Apoptosis and Pro-Inflammatory Cytokine Gene Expression in a Murine Model of Focal Retinal Degeneration

    Directory of Open Access Journals (Sweden)

    Yujuan Wang

    2013-10-01

    Full Text Available AMD (age-related macular degeneration is a neurodegenerative disease causing irreversible central blindness in the elderly. Apoptosis and inflammation play important roles in AMD pathogenesis. PEDF (pigment epithelium-derived factor is a potent neurotrophic and anti-inflammatory glycoprotein that protects the retinal neurons and photoreceptors against cell death caused by pathological insults. We studied the effects of PEDF on focal retinal lesions in DKO rd8 (Ccl2 −/− /Cx3cr1 −/− on C57BL/6N [Crb1rd8 ] mice, a model for progressive, focal rd (retinal degeneration. First, we found a significant decrease in PEDF transcript expression in DKO rd8 mouse retina and RPE (retinal pigment epithelium than WT (wild-type, C57BL/6N. Next, cultured DKO rd8 RPE cells secreted lower levels of PEDF protein in the media than WT. Then the right eyes of DKO rd8 mice were injected intravitreously with recombinant human PEDF protein (1 μg, followed by a subconjunctival injection of PEDF (3 μg 4 weeks later. The untreated left eyes served as controls. The effect of PEDF was assessed by fundoscopy, ocular histopathology and A2E {[2,6-dimethyl-8-(2,6,6-trimethyl-1-cyclohexen-1-yl-1E,3E,5E,7E-octatetra-enyl]-1-(2-hydroxyethyl-4-[4-methyl-6(2,6,6-trimethyl-1-cyclohexen-1-yl 1E,3E,5E,7E-hexatrienyl]-pyridinium} levels, as well as apoptotic and inflammatory molecules. The PEDF-treated eyes showed slower progression or attenuation of the focal retinal lesions, fewer and/or smaller photoreceptor and RPE degeneration, and significantly lower A2E, relative to the untreated eyes. In addition, lower expression of apoptotic and inflammatory molecules were detected in the PEDF-treated than untreated eyes. Our results establish that PEDF potently stabilizes photoreceptor degeneration via suppression of both apoptotic and inflammatory pathways. The multiple beneficial effects of PEDF represent a novel approach for potential AMD treatment.

  9. Photodisruption increases the free-radical reactivity of melanosomes isolated from retinal pigment epithelium

    Science.gov (United States)

    Glickman, Randolph D.; Jacques, Steven L.; Schwartz, Jon A.; Rodriguez, Tom; Lam, Kwok-Wai; Buhr, Gwen

    1996-05-01

    Melanin in vivo is usually packaged in melanosomes with protein coats that restrict direct interaction of the melanin with the surrounding medium. We found that disruption of the melanosomes by exposure to a pulsed laser increased the ability of the melanin radicals to oxidize NADPH in a photochemical reaction. Retinal pigment epithelial (RPE) melanosomes were prepared from fresh bovine eyes in 0.25 M sucrose. A reaction mixture of 7 mM NADPH, approximately 7500 RPE melanosomes, and 80 mM Tris buffer, pH 7.2, was prepared in a volume of 60 (mu) l. Of the two 25-(mu) l aliquots taken from this mixture, one was pre-exposed to the 2nd-harmonic output of a Q-switched Nd:YAG laser (532 nm, 1800 10-nsec pulses at 10 Hz), and then was exposed to an Argon ion continuous wave (CW) laser (488.1 and 514.5 nm) for five minutes. The other aliquot was exposed only to the Argon laser. The CW exposure excited the melanin radicals to a reactive state that oxidized NADPH, as assayed by the loss of absorbance at 340 nm. Native melanosomes oxidized less NADPH during Ar+ laser pumping than did melanosomes pre-exposed to the YAG laser. The YAG laser's stimulatory effect on melanosomes reactivity increased as the total energy it delivered rose above 3.5 J (0.14 J/cm2/pulse X 1800 pulses), up to a maximum NADPH oxidation at about 20 J (0.2 J/cm2/pulse X 1800 pulses, beam broadened at higher pulse energy). Electron microscopic analysis of the melanosomes confirmed the progressive physical disruption of melanosomes as the YAG pulse energy increased.

  10. Morphological changes in the retinal pigment epithelium on spectral-domain OCT in the unaffected eyes with idiopathic central serous chorioretinopathy.

    Science.gov (United States)

    Gupta, Pawan; Gupta, Vishali; Dogra, M R; Singh, Ramandeep; Gupta, Amod

    2010-04-01

    To report the changes seen in the retinal pigment epithelium (RPE) morphology in the asymptomatic eyes of patients with idiopathic central serous chorioretinopathy (ICSC) using spectral-domain Cirrus (TM) high-definition optical coherence tomography (HD-OCT). In a prospective case series, 17 consecutive patients with unilateral ICSC underwent spectral-domain Cirrus (TM) HD-OCT scans for both affected and opposite asymptomatic eye. Three-dimensional single-layer RPE map was studied in both eyes for morphological alterations, and findings were correlated with clinical presentation, fluorescein angiogram, and 5 Line raster scan. Additionally, three-dimensional (3D) single-layer RPE maps done in 111 healthy volunteers served as control. In patients with ICSC, 3D single-layer RPE analysis of asymptomatic eyes showed presence of RPE bumps in 16 (94%) eyes and pigment epithelium detachment (PED) in 2 (11.8%) eyes. The 5 Line raster scan was normal in all eyes. Of 222 normal (control) scans, 18 showed RPE bumps and none showed PED. Conclusions 3D single-layer RPE map showed abnormal pattern in the asymptomatic eyes of patients with unilateral ICSC. Spectral-domain optical coherence tomography showed morphologic alterations in retinal pigment epithelium in both eyes of patients with idiopathic central serous chorioretinopathy.

  11. Abl suppresses cell extrusion and intercalation during epithelium folding.

    Science.gov (United States)

    Jodoin, Jeanne N; Martin, Adam C

    2016-09-15

    Tissue morphogenesis requires control over cell shape changes and rearrangements. In the Drosophila mesoderm, linked epithelial cells apically constrict, without cell extrusion or intercalation, to fold the epithelium into a tube that will then undergo epithelial-to-mesenchymal transition (EMT). Apical constriction drives tissue folding or cell extrusion in different contexts, but the mechanisms that dictate the specific outcomes are poorly understood. Using live imaging, we found that Abelson (Abl) tyrosine kinase depletion causes apically constricting cells to undergo aberrant basal cell extrusion and cell intercalation. abl depletion disrupted apical-basal polarity and adherens junction organization in mesoderm cells, suggesting that extruding cells undergo premature EMT. The polarity loss was associated with abnormal basolateral contractile actomyosin and Enabled (Ena) accumulation. Depletion of the Abl effector Enabled (Ena) in abl-depleted embryos suppressed the abl phenotype, consistent with cell extrusion resulting from misregulated ena Our work provides new insight into how Abl loss and Ena misregulation promote cell extrusion and EMT.

  12. Proof of concept for AAV2/5-mediated gene therapy in iPSC-derived retinal pigment epithelium of a choroideremia patient.

    Science.gov (United States)

    Cereso, Nicolas; Pequignot, Marie O; Robert, Lorenne; Becker, Fabienne; De Luca, Valerie; Nabholz, Nicolas; Rigau, Valerie; De Vos, John; Hamel, Christian P; Kalatzis, Vasiliki

    2014-01-01

    Inherited retinal dystrophies (IRDs) comprise a large group of genetically and clinically heterogeneous diseases that lead to progressive vision loss, for which a paucity of disease-mimicking animal models renders preclinical studies difficult. We sought to develop pertinent human cellular IRD models, beginning with choroideremia, caused by mutations in the CHM gene encoding Rab escort protein 1 (REP1). We reprogrammed REP1-deficient fibroblasts from a CHM (-/y) patient into induced pluripotent stem cells (iPSCs), which we differentiated into retinal pigment epithelium (RPE). This iPSC-derived RPE is a polarized monolayer with a classic morphology, expresses characteristic markers, is functional for fluid transport and phagocytosis, and mimics the biochemical phenotype of patients. We assayed a panel of adeno-associated virus (AAV) vector serotypes and showed that AAV2/5 is the most efficient at transducing the iPSC-derived RPE and that CHM gene transfer normalizes the biochemical phenotype. The high, and unmatched, in vitro transduction efficiency is likely aided by phagocytosis and mimics the scenario that an AAV vector encounters in vivo in the subretinal space. We demonstrate the superiority of AAV2/5 in the human RPE and address the potential of patient iPSC-derived RPE to provide a proof-of-concept model for gene replacement in the absence of an appropriate animal model.

  13. Positive association of circulating levels of advanced glycation end products (AGEs) with pigment epithelium-derived factor (PEDF) in a general population.

    Science.gov (United States)

    Yamagishi, Sho-Ichi; Matsui, Takanori; Adachi, Hisashi; Takeuchi, Masayoshi

    2010-02-01

    We have recently found that serum levels of pigment epithelium-derived factor (PEDF), a glycoprotein with anti-oxidative and anti-inflammatory properties, are elevated in proportion to the accumulation of the number of the components of the metabolic syndrome. Since formation and accumulation of advanced glycation end products (AGEs) progress under the metabolic syndrome and that PEDF could inhibit the AGE-elicited tissue damage, it is conceivable that PEDF levels may be increased as a counter-system against AGEs in patients with the metabolic syndrome. However, correlation between circulating levels of AGEs and PEDF in humans remains to be elucidated. In this study, we investigated the relationship between serum AGE and PEDF levels in a general population and examined the effects of AGEs on PEDF gene expression in vitro. One hundred ninety-six Japanese subjects in a general population underwent a complete history and physical examination, determination of blood chemistries, including serum levels of AGEs and PEDF. In multiple regression analyses, creatinine, body mass index, triglycerides, AGEs and insulin were independently correlated with serum PEDF levels. AGEs dose-dependently increased PEDF gene expression in cultured adipocytes and liver cells. Our present study demonstrated first that circulating AGEs were one of the independent correlates of serum levels of PEDF. Adipose tissue and liver may be target organs for the AGE-induced PEDF overexpression in humans. Serum PEDF levels may be elevated in response to circulating AGEs as a counter-system against the AGE-elicited tissue damage.

  14. Profound Re-Organization of Cell Surface Proteome in Equine Retinal Pigment Epithelial Cells in Response to In Vitro Culturing

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    Marius Ueffing

    2012-10-01

    Full Text Available The purpose of this study was to characterize the cell surface proteome of native compared to cultured equine retinal pigment epithelium (RPE cells. The RPE plays an essential role in visual function and represents the outer blood-retinal barrier. We are investigating immunopathomechanisms of equine recurrent uveitis, an autoimmune inflammatory disease in horses leading to breakdown of the outer blood-retinal barrier and influx of autoreactive T-cells into affected horses’ vitrei. Cell surface proteins of native and cultured RPE cells from eye-healthy horses were captured by biotinylation, analyzed by high resolution mass spectrometry coupled to liquid chromatography (LC MS/MS, and the most interesting candidates were validated by PCR, immunoblotting and immunocytochemistry. A total of 112 proteins were identified, of which 84% were cell surface membrane proteins. Twenty-three of these proteins were concurrently expressed by both cell states, 28 proteins exclusively by native RPE cells. Among the latter were two RPE markers with highly specialized RPE functions: cellular retinaldehyde-binding protein (CRALBP and retinal pigment epithelium-specific protein 65kDa (RPE65. Furthermore, 61 proteins were only expressed by cultured RPE cells and absent in native cells. As we believe that initiating events, leading to the breakdown of the outer blood-retinal barrier, take place at the cell surface of RPE cells as a particularly exposed barrier structure, this differential characterization of cell surface proteomes of native and cultured equine RPE cells is a prerequisite for future studies.

  15. 小干扰RNA介导丝氨酸蛋白酶HtrA1沉默对光损伤人视网膜色素上皮细胞的影响%Influence of down-regulation of HtrA1 expression by small interfering RNA on light-injured human retinal pigment epithelium cells

    Institute of Scientific and Technical Information of China (English)

    余天; 邢怡桥; 陈长征

    2016-01-01

    Objective To observe the influence of down-regulation of HtrA1 expression by small interfering RNA on light-injured human retinal pigment epithelium (RPE) cells.Methods Cultured human RPE cells(8th-12th generations)were exposed to the blue light at the intensity of (2000 ± 500) Lux for 6 hours to establish the light injured model.Light injured cells were divided into HtrA1 siRNA group,negative control group and blank control group.HtrA1 siRNA group and negative control group were transfected with HtrA1 siRNA and control siRNA respectively.The proliferation of cells was assayed by CCK-8 method.Transwell test was used to detect the invasion ability of these three groups.Flow cytometry was used to detect the cell cycle and apoptosis.The expression of HtrA1 and vascular endothelial growth factor (VEGF)-A was detected by real time-polymerase chain reaction and Western blot respectively.Results The mRNA and protein level of HtrA1 in the light injured cells increased significantly compared to that in normal RPE cells (t=17.62,15.09;P<0.05).Compared with negative control group and blank control group,the knockdown of HtrA1 in HtrA1 siRNA group was associated with reduced cellular proliferation (t=6.37,4.52),migration (t =9.56,12.13),apoptosis (t =23.37,29.08) and decreased mRNA (t=17.36,11.32,7.29,4.05) and protein levels (t=12.02,15.28,4.98,6.24) of HtrA1 and VEGF-A.Cells of HtrA1 siRNA group mainly remained in G0/G1 phase,the difference was statistically significant (t=6.24,4.93;P <0.05).Conclusion Knockdown of HtrA1 gene may reduce the proliferation,migration capability and apoptosis of light-injured RPE cells,and decrease the expression of VEGF-A.%目的 观察丝氨酸蛋白酶HtrA1沉默对光损伤人视网膜色素上皮(RPE)细胞的影响.方法 体外培养人RPE细胞,取第8~12代生长良好的传代细胞用于实验.将细胞分为正常对照组、光损伤模型组.采用波长400 nm的蓝色节能灯以(2000±500) Lux持续光照RPE细胞6h建立

  16. Effects of PDTC on the Proliferation and PCNA Expression of Human Retinal Pigment Epithelial Cells

    Institute of Scientific and Technical Information of China (English)

    HU Jun; LI Guigang

    2006-01-01

    To investigate the effects of pyrrolidine dithiocarbamate (PDTC) on the proliferation and PCNA (proliferating cell nuclear antigen) expression of cultured human retinal pigment epithelium cells, human retinal pigment epithelium cells (RPE) were cultured from normal adults who died accidentally. The effects of PDTC on the proliferation of RPE cells were examined by using methyl thiazlyl tetrazolium (MTT) assay. The effects of PDTC on the PCNA expression of RPE cells were immunohistochemically examined by employing biological image analysis system (BIAS). After treatment with PDTC of various of concentration ranging from 0.062 to 1 g/L for 24 h, or concentrations ranging from 0. 031 to 1 g/L, the proliferation of RPE cells decreased in a dose-dependent manner. After treatment with PDTC of concentration varying from 0. 062 to 1 g/L for 24 h, the PCNA expression was also suppressed in a dose-dependent manner. It is concluded that PDTC can inhibit the proliferation of RPE cells in vitro in a dose-and time-dependent manner, at least in part,by down-regulating the expression of PCNA. PDTC may be used to prevent and treat the proliferative vitreoretinopathy (PVR).

  17. Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution.

    Science.gov (United States)

    Parichy, David M; Spiewak, Jessica E

    2015-01-01

    Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage, and mate choice and have played important roles in speciation. Here, we review studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post-embryonic, peripheral nerve-associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow-orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns.

  18. Action spectrum for photochemical retinal pigment epithelium (RPE) disruption in an in vivo monkey model

    Science.gov (United States)

    Zhang, Jie; Sabarinathan, Ranjani; Bubel, Tracy; Williams, David R.; Hunter, Jennifer J.

    2016-03-01

    Observations of RPE disruption and autofluorescence (AF) photobleaching at light levels below the ANSI photochemical maximum permissible exposure (MPE) (Morgan et al., 2008) indicates a demand to modify future light safety standards to protect the retina from harm. To establish safe light exposures, we measured the visible light action spectrum for RPE disruption in an in vivo monkey model with fluorescence adaptive optics retinal imaging. Using this high resolution imaging modality can provide insight into the consequences of light on a cellular level and allow for longitudinal monitoring of retinal changes. The threshold retinal radiant exposures (RRE) for RPE disruption were determined for 4 wavelengths (460, 488, 544, and 594 nm). The anaesthetized macaque retina was exposed to a uniform 0.5° × 0.5° field of view (FOV). Imaging within a 2° × 2° FOV was performed before, immediately after and at 2 week intervals for 10 weeks. At each wavelength, multiple RREs were tested with 4 repetitions each to determine the threshold for RPE disruption. For qualitative analysis, RPE disruption is defined as any detectable change from the pre exposure condition in the cell mosaic in the exposed region relative to the corresponding mosaic in the immediately surrounding area. We have tested several metrics to evaluate the RPE images obtained before and after exposure. The measured action spectrum for photochemical RPE disruption has a shallower slope than the current ANSI photochemical MPE for the same conditions and suggests that longer wavelength light is more hazardous than other measurements would suggest.

  19. Spatial pattern of cell geometry and cell-division orientation in zebrafish lens epithelium

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    Toshiaki Mochizuki

    2014-09-01

    Full Text Available Cell proliferation is a key regulator of tissue morphogenesis. We examined cell proliferation and cell division in zebrafish lens epithelium by visualizing cell-cycle phases and nuclear positions, using fluorescent-labeled geminin and histone proteins. Proliferation was low in the anterior region of lens epithelium and higher in the marginal zone anterior to the equator, suggesting that the proliferation zone, called the germinative zone, is formed in zebrafish lens. Interestingly, cell-division orientation was biased longitudinally in the anterior region, shifted from longitudinal to circumferential along the anterior–posterior axis of lens sphere, and was biased circumferentially in the peripheral region. These data suggest that cell-division orientation is spatially regulated in zebrafish lens epithelium. The Hertwig rule indicates that cells tend to divide along their long axes. Orientation of long axes and cell division were biased similarly in zebrafish lens epithelium, suggesting that cell geometry correlates with cell-division orientation. A cell adhesion molecule, E-cadherin, is expressed in lens epithelium. In a zebrafish e-cadherin mutant, the long axes and cell-division orientation were shifted more longitudinally. These data suggest that E-cadherin is required for the spatial pattern of cell geometry and cell-division orientation in zebrafish lens epithelium.

  20. Transplante autólogo do epitélio pigmentado da retina na degeneração macular relacionada com a idade Autologous transplantation of retinal pigment epithelium in age related macular degeneration

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    Rubens Camargo Siqueira

    2009-02-01

    thought to induce age-related macular degeneration in susceptible individuals. In the past 20 years, a huge amount of research has been conducted in the area of transplantation of RPE. This technique aims to restore the subretinal anatomy and reestablish the critical interaction between the retinal pigment epithelium and the photoreceptor, which is fundamental to sight. Retinal pigment epithelial transplantation has been performed with two different techniques: retinal pigment epithelial suspension and autologous full-thickness retinal pigment epithelial-choroid transplantation in some cases of the age-related macular degeneration (AMD. Despite the feasibility of this technique, search for a cell source to replace autologous retinal pigment epithelium such as embryonic stem cells, marrow-derived stem cells and umbilical cord-derived cells continues. The combination of cell transplantation with other modalities of treatment such as gene transfer remains an exciting future prospect.

  1. Angiotensin-2-mediated Ca2+ signaling in the retinal pigment epithelium: role of angiotensin-receptor-associated-protein and TRPV2 channel.

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    Rene Barro-Soria

    Full Text Available Angiotensin II (AngII receptor (ATR is involved in pathologic local events such as neovascularisation and inflammation including in the brain and retina. The retinal pigment epithelium (RPE expresses ATR in its AT1R form, angiotensin-receptor-associated protein (Atrap, and transient-receptor-potential channel-V2 (TRPV2. AT1R and Atrap co-localize to the basolateral membrane of the RPE, as shown by immunostaining. Stimulation of porcine RPE (pRPE cells by AngII results in biphasic increases in intracellular free Ca(2+inhibited by losartan. Xestospongin C (xest C and U-73122, blockers of IP3R and PLC respectively, reduced AngII-evoked Ca(2+response. RPE cells from Atrap(-/- mice showed smaller AngII-evoked Ca(2+peak (by 22% and loss of sustained Ca(2+elevation compared to wild-type. The TRPV channel activator cannabidiol (CBD at 15 µM stimulates intracellular Ca(2+-rise suggesting that porcine RPE cells express TRPV2 channels. Further evidence supporting the functional expression of TRPV2 channels comes from experiments in which 100 µM SKF96365 (a TRPV channel inhibitor reduced the cannabidiol-induced Ca(2+-rise. Application of SKF96365 or reduction of TRPV2 expression by siRNA reduced the sustained phase of AngII-mediated Ca(2+transients by 53%. Thus systemic AngII, an effector of the local renin-angiotensin system stimulates biphasic Ca(2+transients in the RPE by releasing Ca(2+from cytosolic IP3-dependent stores and activating ATR/Atrap and TRPV2 channels to generate a sustained Ca(2+elevation.

  2. 不同波长的光照射对视网膜色素上皮细胞生长及其分泌生长因子的影响%Effects of different wave-length lights on proliferation and secretion of growth factors in human retinal pigment epithelium cells

    Institute of Scientific and Technical Information of China (English)

    郑晓汾; 康玉国; 褚仁远

    2011-01-01

    异均有统计学意义(P<0.05)。RT-PCR结果显示,不同波长光照射后RPE细胞中HGF mRNA的表达水平不同,蓝光下培养的RPE细胞HGF mRNA表达量最少,白光组、红光组和蓝光组HGF mRNA的表达量(A490)与对照组比较差异均有统计学意义( P<0.05)。透射电子显微镜下红光组、白光组人胚RPE细胞与对照组相比超微结构均无明显变化,但蓝光组RPE细胞核染色质稀疏变淡,细胞器减少,细胞界膜不清或消失。结论不同波长的光照射可影响人RPE细胞的增生及其分泌HGF、bFGF和TGF-β的功能,提示近视的形成可能与不同波长的光相互作用有关。%Background The study of myopia development is always the hotspot worldwide. Recently,scientist found that some growth factor secreted by retinal nerve epithelium cells and retinal pigment epithelium(RPE)cells are associated with the development of myopia. Whenever, the absorption of RPE cells to different wave-length lights is different. ObjectiveThis study was to investigate the effects of different wave-lengths lights on the proliferation of human RPE cells, and explore the influence of different wave-lengths lights on RPE cells secreting hepatocyte growth factor(HGF) ,basic fibroblast growth factor(bFGF) and transforming growth factor-β(TGF-β).Methods The fourth to fifth passages of human embryonic RPE cells were exposed to blue light( λ =480 nm),red light( λ =775 nm) and white light. The cells of control group were harvested in normal condition. The proliferation and growth of RPE cells were assayed by MTT,and the ultrastructure of cells was examined under the transmission electron microscopy at 48 hours after light exposure of RPE cells. Enzyme linked immunosorbent assay(ELISA) was adopted to determine the concentrations of HGF,bFGF and TGF-β in the culture medium in 12,24,48,72 hours. The expression of HGF mRNA in RPE cells was detected by RT-PCR. This study was approved by Ethic committee of Fudan University. Results

  3. Quantification of PCNA+ cells within odontogenic jaw cyst epithelium.

    Science.gov (United States)

    Li, T J; Browne, R M; Matthews, J B

    1994-04-01

    The aim of this study was to investigate the reactivity of the epithelial linings of the three major types of odontogenic cyst with a monoclonal antibody to proliferating cell nuclear antigen (PCNA; clone PC10). PCNA expression was studied in odontogenic cysts (n = 31) and normal oral epithelium (n = 10) using a biotin-streptavidin method on routinely processed paraffin sections. PCNA+ cells were counted manually and related to the length of basement membrane (mm) and the epithelial area (mm2) as determined by TV image analysis. The epithelial linings of odontogenic keratocysts (OKC; n = 11) contained the highest number of PCNA+ cells, most of which were located in the suprabasal layers. The mean value of PCNA+ cells in OKC linings (94.4 +/- 22.7 cells/mm) was similar to that of oral epithelia (80.8 +/- 20.6 cells/mm), but both were significantly higher than that of dentigerous (n = 10, 5.1 +/- 3.0 cells/mm) and radicular (n = 10, 11.0 +/- 4.1 cells/mm) cyst linings (P < 0.005). The epithelial distribution of PCNA+ cells differed between groups with the basal/suprabasal PCNA+ cell ratio in OKC linings (0.05 +/- 0.02) being significantly lower than that of normal oral epithelium (0.5 +/- 0.14), dentigerous (1.6 +/- 1.23) and radicular (1.9 +/- 1.09) cyst linings respectively (P < 0.005). These results demonstrate differences in PCNA expression between the epithelial linings of the major odontogenic cyst types, indicating differences in proliferative and differentiation processes within these lesions.

  4. Cigarette smoke-related hydroquinone dysregulates MCP-1, VEGF and PEDF expression in retinal pigment epithelium in vitro and in vivo.

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    Marianne Pons

    Full Text Available BACKGROUND: Age-related macular degeneration (AMD is the leading cause of legal blindness in the elderly population. Debris (termed drusen below the retinal pigment epithelium (RPE have been recognized as a risk factor for dry AMD and its progression to wet AMD, which is characterized by choroidal neovascularization (CNV. The underlying mechanism of how drusen might elicit CNV remains undefined. Cigarette smoking, oxidative damage to the RPE and inflammation are postulated to be involved in the pathophysiology of the disease. To better understand the cellular mechanism(s linking oxidative stress and inflammation to AMD, we examined the expression of pro-inflammatory monocyte chemoattractant protein-1 (MCP-1, pro-angiogenic vascular endothelial growth factor (VEGF and anti-angiogenic pigment epithelial derived factor (PEDF in RPE from smoker patients with AMD. We also evaluated the effects of hydroquinone (HQ, a major pro-oxidant in cigarette smoke on MCP-1, VEGF and PEDF expression in cultured ARPE-19 cells and RPE/choroids from C57BL/6 mice. PRINCIPAL FINDINGS: MCP-1, VEGF and PEDF expression was examined by real-time PCR, Western blot, and ELISA. Low levels of MCP-1 protein were detected in RPE from AMD smoker patients relative to controls. Both MCP-1 mRNA and protein were downregulated in ARPE-19 cells and RPE/choroids from C57BL/6 mice after 5 days and 3 weeks of exposure to HQ-induced oxidative injury. VEGF protein expression was increased and PEDF protein expression was decreased in RPE from smoker patients with AMD versus controls resulting in increased VEGF/PEDF ratio. Treatment with HQ for 5 days and 3 weeks increased the VEGF/PEDF ratio in vitro and in vivo. CONCLUSION: We propose that impaired RPE-derived MCP-1-mediated scavenging macrophages recruitment and phagocytosis might lead to incomplete clearance of proinflammatory debris and infiltration of proangiogenic macrophages which along with increased VEGF/PEDF ratio favoring

  5. Alginate as a cell culture substrate for growth and differentiation of human retinal pigment epithelial cells.

    Science.gov (United States)

    Heidari, Razeih; Soheili, Zahra-Soheila; Samiei, Shahram; Ahmadieh, Hamid; Davari, Maliheh; Nazemroaya, Fatemeh; Bagheri, Abouzar; Deezagi, Abdolkhalegh

    2015-03-01

    The purpose of this study was to evaluate retinal pigment epithelium (RPE) cells' behavior in alginate beads that establish 3D environment for cellular growth and mimic extracellular matrix versus the conventional 2D monolayer culture. RPE cells were encapsulated in alginate beads by dripping alginate cell suspension into CaCl2 solution. Beads were suspended in three different media including Dulbecco's modified Eagle's medium (DMEM)/F12 alone, DMEM/F12 supplemented with 10 % fetal bovine serum (FBS), and DMEM/F12 supplemented with 30 % human amniotic fluid (HAF). RPE cells were cultivated on polystyrene under the same conditions as controls. Cell phenotype, cell proliferation, cell death, and MTT assay, immunocytochemistry, and real-time RT-PCR were performed to evaluate the effect of alginate on RPE cells characteristics and integrity. RPE cells can survive and proliferate in alginate matrixes. Immunocytochemistry analysis exhibited Nestin, RPE65, and cytokeratin expressions in a reasonable number of cultured cells in alginate beads. Real-time PCR data demonstrated high levels of Nestin, CHX10, RPE65, and tyrosinase gene expressions in RPE cells immobilized in alginate when compared to 2D monolayer culture systems. The results suggest that alginate can be used as a reliable scaffold for maintenance of RPE cells' integrity and in vitro propagation of human retinal progenitor cells for cell replacement therapies in retinal diseases.

  6. A constitutively active Gαi3 protein corrects the abnormal retinal pigment epithelium phenotype of Oa1-/- mice.

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    Alejandra Young

    Full Text Available PURPOSE: Ocular Albinism type 1 (OA1 is a disease caused by mutations in the OA1 gene and characterized by the presence of macromelanosomes in the retinal pigment epithelium (RPE as well as abnormal crossing of the optic axons at the optic chiasm. We showed in our previous studies in mice that Oa1 activates specifically Gαi3 in its signaling pathway and thus, hypothesized that a constitutively active Gαi3 in the RPE of Oa1-/- mice might keep on the Oa1 signaling cascade and prevent the formation of macromelanosomes. To test this hypothesis, we have generated transgenic mice that carry the constitutively active Gαi3 (Q204L protein in the RPE of Oa1-/- mice and are now reporting the effects that the transgene produced on the Oa1-/- RPE phenotype. METHODS: Transgenic mice carrying RPE-specific expression of the constitutively active Gαi3 (Q204L were generated by injecting fertilized eggs of Oa1-/- females with a lentivirus containing the Gαi3 (Q204L cDNA. PCR, Southern blots, Western blots and confocal microscopy were used to confirm the presence of the transgene in the RPE of positive transgenic mice. Morphometrical analyses were performed using electron microscopy to compare the size and number of melanosomes per RPE area in putative Oa1-/-, Gαi3 (Q204L transgenic mice with those of wild-type NCrl and Oa1-/- mice. RESULTS: We found a correlation between the presence of the constitutively active Gαi3 (Q204L transgene and the rescue of the normal phenotype of RPE melanosomes in Oa1-/-, Gαi3 (Q204L mice. These mice have higher density of melanosomes per RPE area and a larger number of small melanosomes than Oa1-/- mice, and their RPE phenotype is similar to that of wild-type mice. CONCLUSIONS: Our results show that a constitutively active Gαi3 protein can by-pass the lack of Oa1 protein in Oa1-/- mice and consequently rescue the RPE melanosomal phenotype.

  7. Understanding age-related macular degeneration (AMD): relationships between the photoreceptor/retinal pigment epithelium/Bruch's membrane/choriocapillaris complex.

    Science.gov (United States)

    Bhutto, Imran; Lutty, Gerard

    2012-08-01

    There is a mutualistic symbiotic relationship between the components of the photoreceptor/retinal pigment epithelium (RPE)/Bruch's membrane (BrMb)/choriocapillaris (CC) complex that is lost in AMD. Which component in the photoreceptor/RPE/BrMb/CC complex is affected first appears to depend on the type of AMD. In atrophic AMD (~85-90% of cases), it appears that large confluent drusen formation and hyperpigmentation (presumably dysfunction in RPE) are the initial insult and the resorption of these drusen and loss of RPE (hypopigmentation) can be predictive for progression of geographic atrophy (GA). The death and dysfunction of photoreceptors and CC appear to be secondary events to loss in RPE. In neovascular AMD (~10-15% of cases), the loss of choroidal vasculature may be the initial insult to the complex. Loss of CC with an intact RPE monolayer in wet AMD has been observed. This may be due to reduction in blood supply because of large vessel stenosis. Furthermore, the environment of the CC, basement membrane and intercapillary septa, is a proinflammatory milieu with accumulation of complement components as well as proinflammatory molecules like CRP during AMD. In this toxic milieu, CC die or become dysfunction making adjacent RPE hypoxic. These hypoxic cells then produce angiogenic substances like VEGF that stimulate growth of new vessels from CC, resulting in choroidal neovascularization (CNV). The loss of CC might also be a stimulus for drusen formation since the disposal system for retinal debris and exocytosed material from RPE would be limited. Ultimately, the photoreceptors die of lack of nutrients, leakage of serum components from the neovascularization, and scar formation. Therefore, the mutualistic symbiotic relationship within the photoreceptor/RPE/BrMb/CC complex is lost in both forms of AMD. Loss of this functionally integrated relationship results in death and dysfunction of all of the components in the complex.

  8. 色素上皮细胞源性因子的抗肿瘤活性%Anti-tumor effects of pigment epithelium-derived factor

    Institute of Scientific and Technical Information of China (English)

    任远; 张锡林

    2011-01-01

    色素上皮细胞源性因子(PEDF)是一种最早从人类胚胎视网膜色素上皮中发现的相对分子质量约为50 KDa的分泌糖蛋白.PEDF广泛存在于人体内多个器官和组织中,且其表达量与人体内多项病理生理过程密切相关.最近研究表明,PEDF在肿瘤的生长、侵袭和转移过程中发挥着重要作用.肿瘤组织中的微血管密度与肿瘤的生长速度呈正相关,作为目前已知的最强的内源性血管生成抑制因子,PEDF能够通过抑制肿瘤血管生成而抑制肿瘤的生长.此外,PEDF亦能通过激活多种复杂信号转导通路诱导肿瘤细胞的凋亡.%PEDF is a 50-kDa secreted glycoprotein first discovered as a factor secreted by the retina pigmented epithelium of the human foetal eye. PEDF is widely spread in human tissues and organs, and its expression is related to the function of human body. Recent studies have shown that PEDF plays an important role in tumor growth, invasion, and metastasis. As we know, microvessel density is correlated with the rapid growth of tumor cells. As the most potent endogenous angiogenesis inhibitor, PEDF can suppress tumor growth by inhibiting angiogenesis. In addition, PEDF can also induce apoptosis through activating complex signal transduction pathways.

  9. Establishment of a blue light damage model of human retinal pigment epithelial cells in vitro.

    Science.gov (United States)

    Su, G; Cai, S J; Gong, X; Wang, L L; Li, H H; Wang, L M

    2016-06-24

    To establish a blue-light damage model of human retinal pigment epithelium (RPE). Fourth-generation human RPE cells were randomly divided into two groups. In group A, cells were exposed to blue light (2000 ± 500 lux) for 0 (control), 3, 6, 9, and 12 h, and cell culture was stopped after 12 h. In group B, cells were exposed to blue light at the same intensity and time periods, but cell culture was stopped after 24 h. TdT-mediated dUTP nick-end labeling (TUNEL) assay was performed to determine the most suitable illuminating time with apoptotic index. Flow cytometry was used to determine apoptotic ratio of RPEs. In group A, the apoptotic index of cells that received 6, 9 and 12 h of blue light was higher than that of control. The apoptotic index of cells receiving 9 and 12 h was higher than that of 6 h (P = 0.000). In group B, the apoptotic index and RPE cell apoptosis ratio of cells exposed to 6, 9 and 12 h of blue light were higher than that of 3 h (P = 0.000); and cells receiving 9 and 12 h had higher values than that of 6 h. This study demonstrated that the best conditions to establish a blue light damage model of human retinal pigment epithelial cells in vitro are 2000 ± 500 lux light intensity for 6 h, with 24 h of cell culture post-exposure.

  10. Primary Adult Human Retinal Pigment Epithelial Cell Cultures on Human Amniotic Membranes

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    Singhal Shweta

    2005-01-01

    Full Text Available Purpose: Retinal pigment epithelial (RPE cells grow well on surfaces that provide an extracellular matrix. Our aim was to establish primary adult human RPE cell cultures that retain their epithelial morphology in vitro using human amniotic membrane (hAM as substrate. Materials and Methods: Human cadaver eyeballs (16 were obtained from the eye bank after corneal trephination. RPE cells were harvested by a mechanical dissection of the inner choroid surface (10, group 1 or by b enzymatic digestion using 0.25% Trypsin/0.02% EDTA (6, group 2. The cells were explanted onto de-epithelialized hAM, nourished using DMEM/HAMS F-12 media and monitored for growth under the phase contrast microscope. Cell cultures were characterised by whole mount studies and paraffin sections. Growth data in the two groups were compared using the students′ ′t′ test. Results: Eleven samples (68.75% showed positive cultures with small, hexagonal cells arising from around the explant which formed a confluent and progressively pigmented monolayer. Whole mounts showed closely placed polygonal cells with heavily pigmented cytoplasm and indistinct nuclei. The histologic sections showed monolayers of cuboidal epithelium with variable pigmentation within the cytoplasm. Growth was seen by day 6-23 (average 11.5 days in the mechanical group, significantly earlier ( P Conclusions: Primary adult human RPE cell cultures retain epithelial morphology in vitro when cultured on human amniotic membranes . Mechanical dissection of the inner choroid surface appears to be an effective method of isolating RPE cells and yields earlier growth in cultures as compared to isolation by enzymatic digestion

  11. GABA maintains the proliferation of progenitors in the developing chick ciliary marginal zone and non-pigmented ciliary epithelium.

    Directory of Open Access Journals (Sweden)

    Henrik Ring

    Full Text Available GABA is more than the main inhibitory neurotransmitter found in the adult CNS. Several studies have shown that GABA regulates the proliferation of progenitor and stem cells. This work examined the effects of the GABA(A receptor system on the proliferation of retinal progenitors and non-pigmented ciliary epithelial (NPE cells. qRT-PCR and whole-cell patch-clamp electrophysiology were used to characterize the GABA(A receptor system. To quantify the effects on proliferation by GABA(A receptor agonists and antagonists, incorporation of thymidine analogues was used. The results showed that the NPE cells express functional extrasynaptic GABA(A receptors with tonic properties and that low concentration of GABA is required for a baseline level of proliferation. Antagonists of the GABA(A receptors decreased the proliferation of dissociated E12 NPE cells. Bicuculline also had effects on progenitor cell proliferation in intact E8 and E12 developing retina. The NPE cells had low levels of the Cl-transporter KCC2 compared to the mature retina, suggesting a depolarising role for the GABA(A receptors. Treatment with KCl, which is known to depolarise membranes, prevented some of the decreased proliferation caused by inhibition of the GABA(A receptors. This supported the depolarising role for the GABA(A receptors. Inhibition of L-type voltage-gated Ca(2+ channels (VGCCs reduced the proliferation in the same way as inhibition of the GABA(A receptors. Inhibition of the channels increased the expression of the cyclin-dependent kinase inhibitor p27(KIP1, along with the reduced proliferation. These results are consistent with that when the membrane potential indirectly regulates cell proliferation with hyperpolarisation of the membrane potential resulting in decreased cell division. The increased expression of p27(KIP1 after inhibition of either the GABA(A receptors or the L-type VGCCs suggests a link between the GABA(A receptors, membrane potential, and

  12. Combined Hamartoma of the Retina and Retinal Pigment Epithelium in a Patient with Gorlin Syndrome: Spontaneous Partial Resolution of Traction Caused by Epiretinal Membrane

    Science.gov (United States)

    Sánchez-Vicente, José L.; Rueda, Trinidad; Rodríguez de la Rúa-Franch, Enrique; Molina-Socola, Fredy E.; Vital-Berral, Cristina; Alfaro-Juárez, Asunción; López-Herrero, Fernando; Muñoz-Morales, Ana

    2016-01-01

    Purpose. To describe the case of spontaneous resolution of epiretinal membrane in a patient with Combined Hamartoma of the Retina and Retinal Pigment Epithelium (CHR-RPE), in the clinical context of Gorlin Syndrome (GS). Methods. Observational case report of a 12-year-old female patient is presented. The diagnosis of CHRRPE was made by OCT and fundus examination, which showed a mound of disorganized tissue originating from retina and retinal pigment epithelium. Epiretinal membrane (EM) was also detected. Genetic study was performed to confirm the diagnosis of GS. Results. The patient was observed for 39 months, showing spontaneous resolution of the traction caused by the EM and improvement in visual acuity (VA), which was 20/80 at initial presentation, rising to 20/40 after follow-up period. Conclusions. The presence of EM in CHR-REP is a cause of reduction of visual acuity. Management of this condition is controversial; however, we would like to highlight that spontaneous resolution of the traction caused by EM is possible, resulting in recovery of VA. PMID:27595027

  13. Regional variations of cell surface carbohydrates in human oral stratified epithelium

    DEFF Research Database (Denmark)

    Vedtofte, P; Dabelsteen, Erik; Hakomori, S

    1984-01-01

    such as non-keratinized, parakeratinized, and orthokeratinized stratified squamous epithelium. The material included buccal and palatal epithelium from 20 persons with blood group A or O, gingival, and alveolar epithelium from 10 persons with blood group A or B, and buccal metaplastically keratinized......-acetyllactosamine by murine monoclonal antibodies. Each antigen showed a similar staining pattern in buccal and alveolar epithelium (non-keratinized) which differed considerably from that seen in palatal and gingival epithelium (ortho- and parakeratinized). The expression of blood group antigens A or B and the precursor...... antigen H type 2 chains in metaplastically keratinized buccal epithelium was found to differ significantly from that seen in normal non-keratinized buccal epithelium. The regional variations demonstrated in cell surface carbohydrates are suggested to reflect differences in tissue differentiation....

  14. The adult retinal stem cell is a rare cell in the ciliary epithelium whose progeny can differentiate into photoreceptors

    Directory of Open Access Journals (Sweden)

    Brian G. Ballios

    2012-02-01

    Self-renewing, multipotential retinal stem cells (RSCs reside in the pigmented ciliary epithelium of the peripheral retina in adult mammals. RSCs can give rise to rhodopsin positive-cells, which can integrate into early postnatal retina, and represent a potentially useful option for cellular therapy. The ability to purify a stem cell population and direct the differentiation toward a particular cell lineage is a challenge facing the application of stem cells in regenerative medicine. Here we use cell sorting to prospectively enrich mouse RSCs based on size, granularity and low expression of P-cadherin and demonstrate that only rare cells with defined properties proliferate to form colonies. We show that clonally-derived mouse and human RSC progeny are multipotent and can differentiate into mature rhodopsin-positive cells with high efficiency using combinations of exogenous culture additives known to influence neural retinal development, including taurine and retinoic acid. This directed RSC differentiation follows the temporal sequence of photoreceptor differentiation in vivo, and the cells exhibit morphology, protein and gene expression consistent with primary cultures of rods in vitro. These results demonstrate that the RSC, an adult stem cell, can be enriched and directed to produce photoreceptors as a first step toward a targeted cell replacement strategy to treat retinal degenerative disease.

  15. Bone morphogenetic protein-4 enhances vascular endothelial growth factor secretion by human retinal pigment epithelial cells.

    Science.gov (United States)

    Vogt, Rhonda R; Unda, Richard; Yeh, Lee-Chuan C; Vidro, Eileen K; Lee, John C; Tsin, Andrew T

    2006-08-01

    Retinal pigment epithelial (RPE) cells secrete vascular endothelial growth factor (VEGF), a cytokine known to promote angiogenesis. Results from RNase protection assays (RPAs) show that RPE from non-diabetic human donors and from adult retinal pigment epithelium-19 (ARPE-19) cells expressed significant bone morphogenetic protein-4 (BMP-4) message. In addition, ARPE-19 cells cultured in high glucose (25 mM), compared to those in physiological glucose (5.5 mM) released significantly more BMP-4 into the conditioned media (CM). However, the effect of BMP-4 on the release of VEGF by ARPE-19 cells has not been studied. Accordingly, ARPE-19 cells were treated with BMP-4 to determine VEGF secretion. BMP-4 and VEGF levels in the CM and cell lysates were measured by enzyme-linked immunosorbent assay (ELISA). Cells treated with exogenous BMP-4 had higher VEGF in the CM and this treatment effect was dose- and time-dependent, while cell lysates had low levels of VEGF. Addition of cycloheximide (CHX) or actinomycin-D (ACT) significantly reduced VEGF secretion from cells treated with BMP-4, suggesting that the BMP-4-induced secretion of VEGF requires new RNA and protein synthesis. Our results suggest that BMP-4 may play a role in the regulation of ocular angiogenesis associated with diabetic retinopathy (DR) by stimulating VEGF release from RPE cells.

  16. Histological and electrophysiological changes in the retinal pigment epithelium after injection of sodium iodate in the orbital venus plexus of pigmented rats

    Directory of Open Access Journals (Sweden)

    Hamid Aboutaleb Kadkhodaeian

    2016-01-01

    Conclusion: NaIO3injection into the retrobulbar venous plexus of pigmented rats can result in significant and progressive damage to the RPE and subsequently to the neuroretina of the injected eye, and may serve as a model of retinal degeneration.

  17. Cross-talk between ciliary epithelium and trabecular meshwork cells in-vitro: a new insight into glaucoma.

    Directory of Open Access Journals (Sweden)

    Natalie Lerner

    Full Text Available PURPOSE: It is assumed that the non-pigmented ciliary epithelium plays a role in regulating intraocular pressure via its neuroendocrine activities. To test this hypothesis, we investigated the effect on a human trabecular meshwork (TM cell line (NTM of co-culture with a human non-pigmented ciliary epithelium cell line (ODM-2. METHODS: The cellular cross-talk between ODM-2 and NTM cells was studied in a co-culture system in which the two cell types were co-cultured for 5 to 60 min or 2, 4 and 8h and then removed from the co-culture and analyzed. Analyses of the ERK and p38 mitogen-activated protein kinase (MAPK pathways and of the activity of TM phosphatases and matrix metalloproteins (MMPs were performed. Acid and alkaline phosphatase activity was determined by the DiFMUP (6, 8-difluoro-4-methylumbelliferyl phosphate assay. MMP levels were determined by gelatin zymography. RESULTS: Exposure of NTM cells to ODM-2 cells led to the activation of the MAPK signal transduction pathways in NTM cells within 5 min of co-culture. Phosphorylation of ERK1/ERK2 and p38 peaked at 10 and 15 min and then decreased over time. Interaction between ODM-2 and NTM cells promoted the expression of MMP-9 in the NTM cells after 4h of co-culture. CONCLUSIONS: Our findings provide support for the hypothesis that crosstalk does indeed take place between ODM-2 and NTM cells. Future studies should be designed to determine the relationship between the MMP system, MAPK kinases and phosphatases. Manipulation of these signaling molecules and the related NTM signal transduction pathways may provide targets for developing improved treatments for glaucoma.

  18. HAIR CELL-LIKE CELL GENERATION INDUCED BY NATURE CULTURE OF ADULT RAT AUDITORY EPITHELIUM

    Institute of Scientific and Technical Information of China (English)

    Liu Hui; Zhu Hongliang; Li Shengli; Yao Xiaobao; Wang Xiaoxia

    2006-01-01

    Objective To establish adult rat auditory epithelial cell culture and try to find precursor cells of auditory hair cells in vitro. Methods With refinement of culture media and techniques, cochlear sensory epithelial cells of adult rat were cultured. Immunocytochemistry and Bromodeoxyuridine (BrdU)labeling were used to detect properties and mitotic status of cultured cells. Results The cultured auditory epithelial cells showed a large, flat epithelial morphotype and expressed F-actin and cytokeratin, a subset of cells generated from auditory epithelium were labeled by calretinin, a specific marker of early hair cell. Conclusion Adult rat auditory epithelium can be induced to generate hair cell-like cells by nature culture, this phenomenon suggests that progenitor cells may exist in rat cochlea and they may give birth to new hair cells. Whether these progenitor cells are tissue specific stem cells is still need more study.

  19. Multiphoton absorption is probably not the primary threshold damage mechanism for femtosecond laser pulse exposures in the retinal pigment epithelium

    Science.gov (United States)

    Glickman, Randolph D.; Johnson, Thomas E.

    2004-07-01

    Laser induced breakdown has the lowest energy threshold in the femtosecond domain, and is responsible for production of threshold ocular lesions. It has been proposed that multiphoton absorption may also contribute to ultrashort-pulse tissue damage, based on the observation that 33 fs, 810 nm pulse laser exposures caused more DNA breakage in cultured, primary RPE cells, compared to CW laser exposures delivering the same average power. Subsequent studies, demonstrating two-photon excitation of fluorescence in isolated RPE melanosomes, appeared to support the role of multiphoton absorption, but mainly at suprathreshold irradiance. Additional experiments have not found a consistent difference in the DNA strand breakage produced by ultrashort and CW threshold exposures. DNA damage appears to be dependent on the amount of melanin pigmentation in the cells, rather than the pulsewidth of the laser; current studies have found that, at threshold, CW and ultrashort pulse laser exposures produce almost identical amounts of DNA breakage. A theoretical analysis suggest that the number of photons delivered to the RPE melanosome during a single 33-fsec pulse at the ED50 irradiance is insufficient to produce multiphoton excitation. This result appears to exclude the melanosome as a locus for two- or three-photon excitation; however, a structure with a larger effective absorption cross-section than the melanosome may interact with the laser pulses. One possibility is that the nuclear chromatin acts as a unit absorber of photons resulting in DNA damage, but this does not explain the near equivalence of ultrashort and CW exposures in the comet assay model. This equivalence indicated that multiphoton absorption is not a major contributor to the ultrashort pulse laser damage threshold in the near infrared.

  20. Coordinate reduction in cell proliferation and cell death in mouse olfactory epithelium from birth to maturity

    NARCIS (Netherlands)

    Fung, KM; Peringa, J; Venkatachalam, S; Lee, VMY; Trojanowski, JQ

    1997-01-01

    We investigated cell proliferation and cell death in the olfactory epithelium (OE) of mice from birth to maturity using bromodeoxyuridine and terminal deoxynucleotidyl transferase nick end labeling. We show that cell death events and proliferative activity diminish concomitantly with age in the OE.

  1. Coordinate reduction in cell proliferation and cell death in mouse olfactory epithelium from birth to maturity

    NARCIS (Netherlands)

    Fung, KM; Peringa, J; Venkatachalam, S; Lee, VMY; Trojanowski, JQ

    1997-01-01

    We investigated cell proliferation and cell death in the olfactory epithelium (OE) of mice from birth to maturity using bromodeoxyuridine and terminal deoxynucleotidyl transferase nick end labeling. We show that cell death events and proliferative activity diminish concomitantly with age in the OE.

  2. Generation of corneal epithelial cells from induced pluripotent stem cells derived from human dermal fibroblast and corneal limbal epithelium.

    Directory of Open Access Journals (Sweden)

    Ryuhei Hayashi

    Full Text Available Induced pluripotent stem (iPS cells can be established from somatic cells. However, there is currently no established strategy to generate corneal epithelial cells from iPS cells. In this study, we investigated whether corneal epithelial cells could be differentiated from iPS cells. We tested 2 distinct sources: human adult dermal fibroblast (HDF-derived iPS cells (253G1 and human adult corneal limbal epithelial cells (HLEC-derived iPS cells (L1B41. We first established iPS cells from HLEC by introducing the Yamanaka 4 factors. Corneal epithelial cells were successfully induced from the iPS cells by the stromal cell-derived inducing activity (SDIA differentiation method, as Pax6(+/K12(+ corneal epithelial colonies were observed after prolonged differentiation culture (12 weeks or later in both the L1B41 and 253G1 iPS cells following retinal pigment epithelial and lens cell induction. Interestingly, the corneal epithelial differentiation efficiency was higher in L1B41 than in 253G1. DNA methylation analysis revealed that a small proportion of differentially methylated regions still existed between L1B41 and 253G1 iPS cells even though no significant difference in methylation status was detected in the specific corneal epithelium-related genes such as K12, K3, and Pax6. The present study is the first to demonstrate a strategy for corneal epithelial cell differentiation from human iPS cells, and further suggests that the epigenomic status is associated with the propensity of iPS cells to differentiate into corneal epithelial cells.

  3. Evaluation of ultraviolet light toxicity on cultured retinal pigment epithelial and retinal ganglion cells

    Directory of Open Access Journals (Sweden)

    Sankarathi Balaiya

    2010-01-01

    Full Text Available Sankarathi Balaiya, Ravi K Murthy, Vikram S Brar, Kakarla V ChalamDepartment of Ophthalmology, University of Florida College of Medicine, Jacksonville, FL, USAPurpose: Our study is aimed at evaluating the role of UVB light in inducing cytotoxicity in an in vitro model.Methods: RGC-5 and ARPE-19 cells were exposed to different time periods of UVB light: 0, 15, 30, and 45 min. They were subsequently examined for changes in cell morphology, cell viability (neutral red uptake assay, generation of reactive oxygen species (ROS, expression of bax, bcl-2 and cytochome C by reverse transcriptase polymerase chain reaction and western blot, respectively.Results: Dose-dependent reduction in cell viability to UVB light was demonstrated with parallel increase in ROS. Increased duration of exposure (>15 minutes, was associated with increased expression of bax and cytochrome C, and absence of bcl-2 expression.Conclusion: UVB light exposure results in cell cytotoxicity. The concomitant generation of ROS and expression of apoptotic markers suggests the role of oxidative stress in UVB-mediated apoptosis in an in vitro model of retinal ganglion and pigment epithelial cells.Keywords: ultraviolet light, retinal pigment epithelium, retinal ganglion cell, reactive oxygen species, cytochrome C

  4. Lutein Inhibits the Migration of Retinal Pigment Epithelial Cells via Cytosolic and Mitochondrial Akt Pathways (Lutein Inhibits RPE Cells Migration

    Directory of Open Access Journals (Sweden)

    Ching-Chieh Su

    2014-08-01

    Full Text Available During the course of proliferative vitreoretinopathy (PVR, the retinal pigment epithelium (RPE cells will de-differentiate, proliferate, and migrate onto the surfaces of the sensory retina. Several studies have shown that platelet-derived growth factor (PDGF can induce migration of RPE cells via an Akt-related pathway. In this study, the effect of lutein on PDGF-BB-induced RPE cells migration was examined using transwell migration assays and Western blot analyses. We found that both phosphorylation of Akt and mitochondrial translocation of Akt in RPE cells induced by PDGF-BB stimulation were suppressed by lutein. Furthermore, the increased migration observed in RPE cells with overexpressed mitochondrial Akt could also be suppressed by lutein. Our results demonstrate that lutein can inhibit PDGF-BB induced RPE cells migration through the inhibition of both cytoplasmic and mitochondrial Akt activation.

  5. Bimonthly half-dose ranibizumab in large pigment epithelial detachment and retinal angiomatous proliferation with high risk of retinal pigment epithelium tear: a case report

    Directory of Open Access Journals (Sweden)

    Monés J

    2013-06-01

    Full Text Available Jordi Monés,1,2 Marc Biarnés,1 Josep Badal11Institut de la Màcula i de la Retina, Barcelona, Spain; 2Barcelona Macula Foundation, Barcelona, SpainIntroduction: The management of large pigment epithelial detachments (PEDs associated with retinal angiomatous proliferation (RAP remains a challenge due to the high risk of retinal pigment epithelial (RPE tear. We describe the successful progressive anatomical result and the maintenance of visual acuity to bimonthly, half-dose ranibizumab in a patient with this condition.Purpose: To describe the management of a large PED secondary to RAP with bimonthly, half-dose ranibizumab.Method: Case report.Patient: A 71-year-old woman presented with visual symptoms due to an enlarged PED, compared with previous visits, secondary to a RAP lesion, with a visual acuity of 20/32. To reduce the risk of an RPE tear and a significant decrease in vision, we discussed with the patient the possibility of treating the lesion in a progressive manner, with more frequent but smaller doses of ranibizumab. The patient was treated biweekly with 0.25 mg of ranibizumab until flattening of the PED.Results: The large PED flattened progressively, and visual acuity was preserved with no adverse events.Discussion: The use of half-dose antiangiogenic therapy may be useful in managing large vascularized PED associated with RAP, in an attempt to reduce the risk of RPE tear.Keywords: age-related macular degeneration, pigment epithelial detachment, ranibizumab, retinal angiomatous proliferation, RPE tear

  6. Mechanism of retinal pigment epithelium tear formation following intravitreal anti-vascular endothelial growth factor therapy revealed by spectral-domain optical coherence tomography

    DEFF Research Database (Denmark)

    Nagiel, Aaron; Freund, K Bailey; Spaide, Richard F;

    2013-01-01

    PURPOSE: To demonstrate the mechanism by which retinal pigment epithelium (RPE) tears occur in eyes with neovascular age-related macular degeneration (AMD) treated with intravitreal anti-vascular endothelial growth factor (VEGF) agents using spectral-domain optical coherence tomography (OCT......). DESIGN: Retrospective observational case series. METHODS: OCT images of 8 eyes that developed RPE tears following the administration of intravitreal anti-VEGF agents for neovascular AMD were evaluated. Pretear and posttear images were compared in order to elucidate the mechanism by which RPE tears occur...... to the retracted RPE. In all eyes, the RPE ruptured along a segment of bare RPE not in contact with the CNV or Bruch membrane. CONCLUSIONS: Eyes with vascularized PEDs secondary to AMD may show specific OCT findings that increase the risk for RPE tear following intravitreal anti-VEGF injection. Rapid involution...

  7. Limited Restoration of Cystic Fibrosis Lung Epithelium In Vivo with Adult Bone Marrow–derived Cells

    OpenAIRE

    Loi, Roberto; Beckett, Travis; Goncz, Kaarin K.; Suratt, Benjamin T.; Weiss, Daniel J.

    2005-01-01

    Rationale: Recent literature suggests that adult bone marrow–derived cells can localize to lung and acquire immunophenotypic characteristics of lung epithelial cells. We speculated this might be a potential therapeutic approach for correcting defective lung epithelium in cystic fibrosis.

  8. Enhanced generation of retinal progenitor cells from human retinal pigment epithelial cells induced by amniotic fluid

    Directory of Open Access Journals (Sweden)

    Sanie-Jahromi Fatemeh

    2012-04-01

    Full Text Available Abstract Background Retinal progenitor cells are a convenient source of cell replacement therapy in retinal degenerative disorders. The purpose of this study was to evaluate the expression patterns of the homeobox genes PAX6 and CHX10 (retinal progenitor markers during treatment of human retinal pigment epithelium (RPE cells with amniotic fluid (AF, RPE cells harvested from neonatal cadaver globes were cultured in a mixture of DMEM and Ham's F12 supplemented with 10% FBS. At different passages, cells were trypsinized and co-cultured with 30% AF obtained from normal fetuses of 1416 weeks gestational age. Results Compared to FBS-treated controls, AF-treated cultures exhibited special morphological changes in culture, including appearance of spheroid colonies, improved initial cell adhesion and ordered cell alignment. Cell proliferation assays indicated a remarkable increase in the proliferation rate of RPE cells cultivated in 30% AF-supplemented medium, compared with those grown in the absence of AF. Immunocytochemical analyses exhibited nuclear localization of retinal progenitor markers at a ratio of 33% and 27% for CHX10 and PAX6, respectively. This indicated a 3-fold increase in retinal progenitor markers in AF-treated cultures compared to FBS-treated controls. Real-time PCR data of retinal progenitor genes (PAX6, CHX10 and VSX-1 confirmed these results and demonstrated AF's capacity for promoting retinal progenitor cell generation. Conclusion Taken together, the results suggest that AF significantly promotes the rate of retinal progenitor cell generation, indicating that AF can be used as an enriched supplement for serum-free media used for the in vitro propagation of human progenitor cells.

  9. Cotransport of H+, lactate, and H2O in porcine retinal pigment epithelial cells

    DEFF Research Database (Denmark)

    Hamann, Steffen; Kiilgaard, Jens Folke; la Cour, Morten

    2003-01-01

    The retinal pigment epithelium (RPE) of the eye transports water and lactate ions in the direction from retina to choroid. The water transport is important in maintenance of retinal adhesion and the transport of lactate ions serves to regulate the lactate levels and pH of the subretinal space....... This study investigates by means of a non-invasive technique the mechanism of coupling between transport of H(+), lactate ion, and water in the monocarboxylate transporter (MCT1) located in the apical (retinal) membrane of a mammalian RPE. Primary cultures of porcine RPE cells were grown to confluence...... using the fluorescent dye BCECF. In lactate-free solutions, mannitol addition to the retinal bath caused intracellular acidification and cell shrinkage, given by a single osmotic water permeability of 1.2+/-0.1 x 10(-4)cmsec(-1) (osmoll(-1))(-1). In solutions containing 50 mmoll(-1) lactate, however...

  10. Epithelial cell extrusion leads to breaches in the intestinal epithelium.

    Science.gov (United States)

    Liu, Julia J; Davis, Elisabeth M; Wine, Eytan; Lou, Yuefei; Rudzinski, Jan K; Alipour, Misagh; Boulanger, Pierre; Thiesen, Aducio L; Sergi, Consolato; Fedorak, Richard N; Muruve, Daniel; Madsen, Karen L; Irvin, Randall T

    2013-04-01

    Two distinct forms of intestinal epithelial cell (IEC) extrusion are described: 1 with preserved epithelial integrity and 1 that introduced breaches in the epithelial lining. In this study, we sought to determine the mechanism underlying the IEC extrusion that alters the permeability of the gut epithelium. IEC extrusions in polarized T84 monolayer were induced with nigericin. Epithelial permeability was assessed with transepithelial electrical resistance and movements of latex microspheres and green fluorescent protein-transfected Escherichia coli across the monolayer. In vivo IEC extrusion was modulated in wild-type and a colitic (interleukin-10 knock-out) mouse model with caspase-1 activation and inhibition. Luminal aspirates and mucosal biopsies from control patients and patients with inflammatory bowel disease were analyzed for caspase-1 and caspase-3&7 activation. Caspase-1-induced IEC extrusion in T84 monolayers resulted in dose-dependent and time-dependent barrier dysfunction, reversible with caspase-1 inhibition. Moreover, the movements of microspheres and microbes across the treated epithelial monolayers were observed. Increased caspase-1-mediated IEC extrusion in interleukin-10 knock-out mice corresponded to enhanced permeation of dextran, microspheres, and translocation of E. coli compared with wild type. Caspase-1 inhibition in interleukin-10 knock-out mice resulted in a time-dependent reduction in cell extrusion and normalization of permeability to microspheres. Increased IEC extrusion in wild-type mice was induced with caspase-1 activation. In human luminal aspirates, the ratio of positively stained caspase-1 to caspase-3&7 cells were 1:1 and 2:1 in control patients and patients with inflammatory bowel disease, respectively; these observations were confirmed by cytochemical analysis of mucosal biopsies. IEC extrusion mediated by caspase-1 activation contributes to altered intestinal permeability in vitro and in vivo.

  11. Putative epidermal stem cell convert into corneal epithelium-like cell under corneal tissue in vitro

    Institute of Scientific and Technical Information of China (English)

    GAO Nan; CUI GuangHui; WANG ZhiChong; HUANG Bing; GE Jian; LU Rong; ZHANG KeFei; FAN ZhiGang; LU Li; PENG Zhan

    2007-01-01

    Rhesus putative epidermal stem cells are being investigated for their potential use in regenerative corneal epithelium-like cells, which may provide a practical source of autologous seed cells for the construction of bioengineered corneas. The goal of this study was to investigate the potential of epidermal stem cells for trans-differentiation into corneal epithelium-like cells. Rhesus putative epidermal stem cells were isolated by type IV collagen attachment method. Flow cytometry analysis, immunohistology and RT-PCR were conducted to identify the expression of specific markers (β1, α6 integrin, K15, K1/K10, K3/K12 and CD71) on the isolated rapid attaching cells. The isolated cells were cocultured with human corneal limbal stroma and corneal epithelial cells. After coculture, the expression of the same specific markers was evaluated in order to identify expression difference caused by the coculture conditions. K3/K12 expression was analyzed in coculture cells on day 2, 4, 6, 8 and 10. Putative epidermal stem cells in conditioned culture media were used as control. Putative epidermal stem cells were predominant in rapid attaching cells by type IV collagen attachment isolation. Before being cocultured, the rhesus putative epidermal stem cells expressed K15, α6 and β1 integrin, but no CD71, K1/K10 and K3/K12. After coculture, these cells expressed K3/K12 (a marker of corneal epithelial cells), K15 and β 1 integrin, but no K1/K10. Cells being not coculture converted into terminally differentiated cells expressing K1/K10. These results indicate that rhesus putative epidermal stem cells can trans-differentiate into corneal epithelium-like cells and, therefore, may have potential therapeutic application as autologous seed cells for the construction of bioengineered corneas.

  12. Putative epidermal stem cell convert into corneal epithelium-like cell under corneal tissue in vitro

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Rhesus putative epidermal stem cells are being investigated for their potential use in regenerative corneal epithelium-like cells, which may provide a practical source of autologous seed cells for the construction of bioengineered corneas. The goal of this study was to investigate the potential of epi-dermal stem cells for trans-differentiation into corneal epithelium-like cells. Rhesus putative epidermal stem cells were isolated by type IV collagen attachment method. Flow cytometry analysis, immuno-histology and RT-PCR were conducted to identify the expression of specific markers (β1, α6 integrin, K15, K1/K10, K3/K12 and CD71) on the isolated rapid attaching cells. The isolated cells were cocultured with human corneal limbal stroma and corneal epithelial cells. After coculture, the expression of the same specific markers was evaluated in order to identify expression difference caused by the coculture conditions. K3/K12 expression was analyzed in coculture cells on day 2, 4, 6, 8 and 10. Putative epi-dermal stem cells in conditioned culture media were used as control. Putative epidermal stem cells were predominant in rapid attaching cells by type IV collagen attachment isolation. Before being co-cultured, the rhesus putative epidermal stem cells expressed K15, α6 and β1 integrin, but no CD71, K1/K10 and K3/K12. After coculture, these cells expressed K3/K12 (a marker of corneal epithelial cells), K15 and β 1 integrin, but no K1/K10. Cells being not coculture converted into terminally differentiated cells expressing K1/K10. These results indicate that rhesus putative epidermal stem cells can trans-differentiate into corneal epithelium-like cells and, therefore, may have potential therapeutic application as autologous seed cells for the construction of bioengineered corneas.

  13. Topical retinoic acid changes the epidermal cell surface glycosylation pattern towards that of a mucosal epithelium

    DEFF Research Database (Denmark)

    Griffiths, C E; Dabelsteen, Erik; Voorhees, J J

    1996-01-01

    in the epidermis and in oral mucosal epithelium. Although type 1 chain structures were not demonstrated in any of the samples, the distribution of type 2 and 3 chain structures in RA-treated epidermis was altered towards that seen in a mucosal epithelium. T antigen, a mucin-type cell surface carbohydrate structure...... normally expressed throughout the epidermis, was only observed in the granular layer of RA-treated epidermis--a feature of mucosal epithelia. Ley, normally only seen in non-keratinized buccal epithelium, was strongly expressed in RA-treated epidermis. In contrast, the glycosylation pattern of the SLS......-treated epidermis was not significantly different from that observed after vehicle treatment. Thus, RA treatment converts normal stratified epithelium towards the phenotype of mucosal epithelium with a decrease in T antigen and a concomitant increase in Ley. These changes are not observed following treatment...

  14. Slit2基因转染对人视网膜色素上皮细胞VEGF表达的影响及其作用机制%Effect of Slit2 gene transfection on vascular endothelial growth factor in retinal pigment epithelium cells and its mechanism

    Institute of Scientific and Technical Information of China (English)

    梅雨; 周希瑗

    2014-01-01

    目的:研究Slit2基因对人视网膜色素上皮(retinal pigment epithelium,RPE)细胞表达血管内皮生长因子(vascular endothelial growth factor,VEGF)的影响,并探讨丝裂原激活(mitogen-activated,MEK)/细胞外信号调节蛋白激酶(extracellular signal regulated protein kinase,ERK)和磷脂酰肌醇-3激酶(phosphatidylinositol 3-kinase,PI3K)/丝氨酸苏氨酸蛋白激酶(serine-threonine kinase,AKT)这2条信号通路在此过程中的作用.方法:(1)体外培养人RPE细胞株RPE-19; (2)将腺病毒介导的Slit2(adenovirus-mediated Slit2,Ad-Slit2)转染RPE细胞,培养12、24 h及48 h;(3)转染前将MEK信号通路阻断剂PD98059、PI3K 信号通路阻断剂LY294002预处理RPE细胞1 h;(4)用real-time PCR及酶联免疫吸附试验(enzyme linked immunosorbent assay,ELISA)检测VEGF的表达水平,用Western blot检测磷酸化ERK、磷酸化AKT的表达情况.结果:Slit2转染的RPE细胞后,real-time PCR结果显示不同时间之间VEGF mRNA表达有差别(F=12.789,P=0.018),组别和时间之间存在交互作用(F=13.375,P=0.017),不同组别有差别(F=16.855,P=0.015),在24 h与48 h,Ad-Slit2组高于空腺病毒组(P4 h=0.002,P48 h=0.018).ELISA结果显示不同时间之间VEGF蛋白表达有差别(F=24.886,P=0.000),组别和时间之间存在交互作用(F=23.524,P=0.000),不同组别有差别(F=28.250,P=0.006),在48 h,Ad-Slit2组高于空腺病毒组(P=0.003).Western blot结果可见p-ERK及p-AKT的蛋白表达水平增加,阻断剂PD98059及LY294002分别能降低ERK、AKT的磷酸化水平,并与Ad-Slit2组相比较,real-time PCR结果显示VEGF mRNA表达水平在不同时间有差别(F=32.202,P=0.000),组别和时间之间存在交互作用(F=8.372,P=0.006);不同组别存在差别(F=15.062,P=0.001),ELISA结果显示VEGF蛋白表达水平在不同时间之间有差别(F=90.703,P=0.000),组别和时间之间存在交互作用(F=4.968,P=0.005),不同组别存在差别(F=69.636,P=0.000).结论:PI3K/AKT以及MEK/ERK这

  15. Macrophages are required for dendritic cell uptake of respiratory syncytial virus from an infected epithelium.

    Science.gov (United States)

    Ugonna, Kelechi; Bingle, Colin D; Plant, Karen; Wilson, Kirsty; Everard, Mark L

    2014-01-01

    We have previously shown that the respiratory syncytial virus [RSV] can productively infect monocyte derived dendritic cells [MoDC] and remain dormant within the same cells for prolonged periods. It is therefore possible that infected dendritic cells act as a reservoir within the airways of individuals between annual epidemics. In the present study we explored the possibility that sub-epithelial DCs can be infected with RSV from differentiated bronchial epithelium and that in turn RSV from DCs can infect the epithelium. A dual co-culture model was established in which a differentiated primary airway epithelium on an Air Liquid Interface (ALI) was cultured on a transwell insert and MoDCs were subsequently added to the basolateral membrane of the insert. Further experiments were undertaken using a triple co-culture model in which in which macrophages were added to the apical surface of the differentiated epithelium. A modified RSV [rr-RSV] expressing a red fluorescent protein marker of replication was used to infect either the MoDCs or the differentiated epithelium and infection of the reciprocal cell type was assessed using confocal microscopy. Our data shows that primary epithelium became infected when rr-RSV infected MoDCs were introduced onto the basal surface of the transwell insert. MoDCs located beneath the epithelium did not become infected with virus from infected epithelial cells in the dual co-culture model. However when macrophages were present on the apical surface of the primary epithelium infection of the basal MoDCs occurred. Our data suggests that RSV infected dendritic cells readily transmit infection to epithelial cells even when they are located beneath the basal layer. However macrophages appear to be necessary for the transmission of infection from epithelial cells to basal dendritic cells.

  16. Pigmented basal cell carcinoma of the eyelid in Hispanics

    Directory of Open Access Journals (Sweden)

    Lily Koo Lin

    2008-10-01

    Full Text Available Lily Koo Lin1, Han Lee2, Eli Chang11Department of Oculoplastics, Doheny Eye Institute, Los Angeles, CA, USA; 2Department of Dermatology, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USABackground: Pigmented basal cell carcinoma (PBCC of the eyelid has not been well cited in the literature, and is often overlooked in the differential diagnosis of pigmented eyelid lesions. We aim to describe PBCC of the eyelid in Hispanic patients.Methods: Retrospective review of patients with eyelid skin cancer who presented to the Department of Dermatology at the Keck School of Medicine of the University of Southern California and the Doheny Eye Institute from January 2002 to November 2005.Results: Sixty-nine of the 79 patients with eyelid skin cancer had basal cell carcinoma. Eight of these patients were Hispanic. Four of the eight Hispanic patients had PBCC.Conclusions: Although eyelid PBCC is regarded as a rare condition, it may occur more commonly in the Hispanic population and should be remembered in the differential diagnosis of pigmented eyelid lesions.Keywords: pigmented basal cell carcinoma, eyelid, skin cancer, lesions

  17. Tooth regeneration from newly established cell lines from a molar tooth germ epithelium.

    Science.gov (United States)

    Komine, Akihiko; Suenaga, Momoko; Nakao, Kazuhisa; Tsuji, Takashi; Tomooka, Yasuhiro

    2007-04-13

    In order to investigate tooth development, several cell lines of the dental epithelium and ectomesenchyme have been established. However, no attempt has been reported to regenerate teeth with cell lines. Here, we have established several clonal cell lines of the dental epithelium from a p53-deficient fetal mouse. They expressed specific markers of the dental epithelium such as ameloblastin and amelogenin. A new method has been developed to bioengineer tooth germs with dental epithelial and mesenchymal cells. Reconstructed tooth germs with cell lines and fetal mesenchymal cells were implanted under kidney capsule. The germs regenerated teeth with well-calcified structures as seen in natural tooth. Germs without the cell lines developed bone. This is the first success to regenerate teeth with dental epithelial cell lines. They are useful models in vitro for investigation of mechanisms in morphogenesis and of cell lineage in differentiation, and for clinical application for tooth regeneration.

  18. Origins and consequences of hyperosmolar stress in retinal pigmented epithelial cells.

    Science.gov (United States)

    Willermain, François; Libert, Sarah; Motulsky, Elie; Salik, Dany; Caspers, Laure; Perret, Jason; Delporte, Christine

    2014-01-01

    The retinal pigmented epithelium (RPE) is composed of retinal pigmented epithelial cells joined by tight junctions and represents the outer blood-retinal barrier (BRB). The inner BRB is made of endothelial cells joined by tight junctions and glial extensions surrounding all the retinal blood vessels. One of the functions of the RPE is to maintain an osmotic transepithelial gradient created by ionic pumps and channels, avoiding paracellular flux. Under such physiological conditions, transcellular water movement follows the osmotic gradient and flows normally from the retina to the choroid through the RPE. Several diseases, such as diabetic retinopathy, are characterized by the BRB breakdown leading to leakage of solutes, proteins, and fluid from the retina and the choroid. The prevailing hypothesis explaining macular edema formation during diabetic retinopathy incriminates the inner BRB breakdown resulting in increased osmotic pressure leading in turn to massive water accumulation that can affect vision. Under these conditions, it has been hypothesized that RPE is likely to be exposed to hyperosmolar stress at its apical side. This review summarizes the origins and consequences of osmotic stress in the RPE. Ongoing and further research advances will clarify the mechanisms, at the molecular level, involved in the response of the RPE to osmotic stress and delineate potential novel therapeutic targets and tools.

  19. Pigment cell differentiation in sea urchin blastula-derived primary cell cultures.

    Science.gov (United States)

    Ageenko, Natalya V; Kiselev, Konstantin V; Dmitrenok, Pavel S; Odintsova, Nelly A

    2014-06-27

    The quinone pigments of sea urchins, specifically echinochrome and spinochromes, are known for their effective antioxidant, antibacterial, antifungal, and antitumor activities. We developed in vitro technology for inducing pigment differentiation in cell culture. The intensification of the pigment differentiation was accompanied by a simultaneous decrease in cell proliferation. The number of pigment cells was two-fold higher in the cells cultivated in the coelomic fluids of injured sea urchins than in those intact. The possible roles of the specific components of the coelomic fluids in the pigment differentiation process and the quantitative measurement of the production of naphthoquinone pigments during cultivation were examined by MALDI and electrospray ionization mass spectrometry. Echinochrome A and spinochrome E were produced by the cultivated cells of the sand dollar Scaphechinus mirabilis in all tested media, while only spinochromes were found in the cultivated cells of another sea urchin, Strongylocentrotus intermedius. The expression of genes associated with the induction of pigment differentiation was increased in cells cultivated in the presence of shikimic acid, a precursor of naphthoquinone pigments. Our results should contribute to the development of new techniques in marine biotechnology, including the generation of cell cultures producing complex bioactive compounds with therapeutic potential.

  20. Tea pigments induce cell-cycle arrest and apoptosis in HepG2 cells

    Institute of Scientific and Technical Information of China (English)

    Xu-Dong Jia; Chi Han; Jun-Shi Chen

    2005-01-01

    AIM: To investigate the molecular mechanisms by which tea pigments exert preventive effects on liver carcinogenesis.METHODS: HepG2 cells were seeded at a density of 5×105/well in six-well culture dishes and incubated overnight. The cells then were treated with various concentrations of tea pigments over 3 d, harvested by trypsinization, and counted using a hemocytometer. Flow cytometric analysis was performed by a flow cytometer after propidium iodide labeling. Bcl-2 and p21WAF1 proteins were determined by Western blotting. In addition, DNA laddering assay was performed on treated and untreated cultured HepG2 cells.RESULTS: Tea pigments inhibited the growth of HepG2 cells in a dose-dependent manner. Flow-cytometric analysis showed that tea pigments arrested cell cycle progression at G1 phase. DNA laddering was used to investigate apoptotic cell death, and the result showed that 100 mg/L of tea pigments caused typical DNA laddering. Our study also showed that tea pigments induced upregulation of p21WAF1 protein and downregulation of Bcl-2 protein.CONCLUSION: Tea pigments induce cell-cycle arrest and apoptosis. Tea pigments may be used as an ideal chemopreventive agent.

  1. Postnatal epithelium and mesenchyme stem/progenitor cells in bioengineered amelogenesis and dentinogenesis.

    Science.gov (United States)

    Jiang, Nan; Zhou, Jian; Chen, Mo; Schiff, Michael D; Lee, Chang H; Kong, Kimi; Embree, Mildred C; Zhou, Yanheng; Mao, Jeremy J

    2014-02-01

    Rodent incisors provide a classic model for studying epithelial-mesenchymal interactions in development. However, postnatal stem/progenitor cells in rodent incisors have not been exploited for tooth regeneration. Here, we characterized postnatal rat incisor epithelium and mesenchyme stem/progenitor cells and found that they formed enamel- and dentin-like tissues in vivo. Epithelium and mesenchyme cells were harvested separately from the apical region of postnatal 4-5 day rat incisors. Epithelial and mesenchymal phenotypes were confirmed by immunocytochemistry, CFU assay and/or multi-lineage differentiation. CK14+, Sox2+ and Lgr5+ epithelium stem cells from the cervical loop enhanced amelogenin and ameloblastin expression upon BMP4 or FGF3 stimulation, signifying their differentiation towards ameloblast-like cells, whereas mesenchyme stem/progenitor cells upon BMP4, BMP7 and Wnt3a treatment robustly expressed Dspp, a hallmark of odontoblastic differentiation. We then control-released microencapsulated BMP4, BMP7 and Wnt3a in transplants of epithelium and mesenchyme stem/progenitor cells in the renal capsule of athymic mice in vivo. Enamel and dentin-like tissues were generated in two integrated layers with specific expression of amelogenin and ameloblastin in the newly formed, de novo enamel-like tissue, and DSP in dentin-like tissue. These findings suggest that postnatal epithelium and mesenchyme stem/progenitor cells can be primed towards bioengineered tooth regeneration.

  2. Semi-automated discrimination of retinal pigmented epithelial cells in two-photon fluorescence images of mouse retinas

    Science.gov (United States)

    Alexander, Nathan S.; Palczewska, Grazyna; Palczewski, Krzysztof

    2015-01-01

    Automated image segmentation is a critical step toward achieving a quantitative evaluation of disease states with imaging techniques. Two-photon fluorescence microscopy (TPM) has been employed to visualize the retinal pigmented epithelium (RPE) and provide images indicating the health of the retina. However, segmentation of RPE cells within TPM images is difficult due to small differences in fluorescence intensity between cell borders and cell bodies. Here we present a semi-automated method for segmenting RPE cells that relies upon multiple weak features that differentiate cell borders from the remaining image. These features were scored by a search optimization procedure that built up the cell border in segments around a nucleus of interest. With six images used as a test, our method correctly identified cell borders for 69% of nuclei on average. Performance was strongly dependent upon increasing retinosome content in the RPE. TPM image analysis has the potential of providing improved early quantitative assessments of diseases affecting the RPE. PMID:26309765

  3. Nonvisual ganglion cells, circuits and nonvisual pigments

    Institute of Scientific and Technical Information of China (English)

    Ali Akbar Kashani; WANG Huai-zhou; WANG Ning-li

    2009-01-01

    @@ To the editor: WANG and his colleagues provided the evidence that "both melanopsin-containing and superior collicular retinal ganglion cells were damaged by chronic ocular hypertension, indicating that glaucomatous neural degeneration involves the non-image-forming visual pathway".

  4. Pigment developed to protect spacecraft/solar cells from Sun's harmful rays.

    Science.gov (United States)

    1995-01-01

    A pigment (phthalocyanine) is studied at the Marshall Materials and Processes Lab. The pigment has the ability to protect spacecraft against the harmful effects of the Sun's ultraviolet rays, and to increase the efficiency and life of solar cells.

  5. Effects of modified LDL and HDL on retinal pigment epithelial cells: a role in diabetic retinopathy?

    Science.gov (United States)

    Du, M; Wu, M; Fu, D; Yang, S; Chen, J; Wilson, K; Lyons, T J

    2013-10-01

    Blood-retina barrier leakage in diabetes results in extravasation of plasma lipoproteins. Intra-retinal modified LDLs have been implicated in diabetic retinopathy (DR), but their effects on retinal pigment epithelial (RPE) cells and the added effects of extravasated modified HDLs are unknown. In human retinas from individuals with and without diabetes and DR, immunohistochemistry was used to detect ApoB, ApoA1 and endoplasmic reticulum (ER) stress markers. In cell culture, human RPE cells were treated with native LDL (N-LDL) or heavily-oxidised glycated LDL (HOG-LDL) with or without pretreatment with native HDL (N-HDL) or heavily-oxidised glycated HDL (HOG-HDL). Cell viability, oxidative stress, ER stress, apoptosis and autophagy were assessed by Cell Counting Kit-8 assay, dichlorofluorescein assay, western blotting, immunofluorescence and TUNEL assay. In separate experiments, RPE cells were treated with lipid oxidation products, 7-ketocholesterol (7-KC, 5-40 μmol/l) or 4-hydroxynonenal (4-HNE, 5-80 μmol/l), with or without pretreatment with N-HDL or HOG-HDL. ApoB, ApoA1 staining and RPE ER stress were increased in the presence of DR. HOG-LDL but not N-LDL significantly decreased RPE cell viability and increased reactive oxygen species generation, ER stress, apoptosis and autophagy. Similarly, 4-HNE and 7-KC decreased viability and induced ER stress. Pretreatment with N-HDL mitigated these effects, whereas HOG-HDL was less effective by most, but not all, measures. In DR, extravascular modified LDL may promote RPE injury through oxidative stress, ER stress, autophagy and apoptosis. N-HDL has protective effects, but HOG-HDL is less effective. Extravasation and modification of HDL may modulate the injurious effects of extravasated modified LDL on the retinal pigment epithelium.

  6. Lactoferrin at basal side of mouse mammary epithelium derives in part from stroma cells.

    Science.gov (United States)

    Pecorini, Chiara; Delpal, Serge; Truchet, Sandrine; Le Provost, Fabienne; Baldi, Antonella; Ollivier-Bousquet, Michèle

    2009-11-01

    Lactoferrin is synthesized by glandular epithelial cells and neutrophils and is also present on both sides of the mammary epithelium. We have studied the origin of lactoferrin detected in the various compartments of mouse mammary tissue. As revealed by immunogold electron microscopy, lactoferrin is present in mammary epithelial cells and in the basal region of the epithelium, associated with connective tissue and stroma cells at all physiological stages studied. A perturbation of protein synthesis or transport after in vitro treatment with cycloheximide or brefeldin A does not abrogate lactoferrin labelling in the basal region of the epithelium. The expression of lactoferrin has also been observed in the fat pads of mammary glands from mice surgically depleted of epithelial cells. The sealing of one teat for 24 h is accompanied by an increase in both the number of stroma cells and the labelling of myoepithelial cells. Thus, the lactoferrin present in the interstitial space of the mouse mammary epithelium originates in part from stroma cells. Possible roles of lactoferrin at the basal side of the mammary epithelium are discussed.

  7. Comparison of Progression Rate of Retinal Pigment Epithelium Loss in Patients with Neovascular Age-Related Macular Degeneration Treated with Ranibizumab and Aflibercept

    Directory of Open Access Journals (Sweden)

    Juliana Wons

    2017-01-01

    Full Text Available Purpose. Retinal pigment epithelium (RPE loss in neovascular age-related macular degeneration (nAMD seem to have a linear progression but might be influenced by the treatment. The purpose of the study is the comparison of RPE loss over three years in patients treated with intravitreal ranibizumab to patients who were switched to aflibercept. Methods. A retrospective analysis with 96 eyes switched to aflibercept was conducted. The progression rate of RPE loss was evaluated in patients who showed atrophy one year prior to switch (n=17 or on switch date (n=19. The RPE loss was evaluated by spectral domain optical coherence tomography (SD-OCT. Further, 22 eyes from patients treated with ranibizumab were compared. Results. The median yearly progression of RPE loss after square root transformation showed no significant difference in the year prior to switch compared to the year after switch (p=0.854. In patients who received only ranibizumab, the median yearly progression of RPE loss was 0.15 mm/y, for aflibercept patients, 0.13 mm/y. This difference was not statistically significant (p=0.172. Conclusions. There seems to be a linear progression rate of RPE loss in patients treated with ranibizumab as well as in patients with aflibercept. No significant increase of progression rate was found after switch to aflibercept.

  8. Down-regulation of pigment epithelium-derived factor in uveitic lesion associates with focal vascular endothelial growth factor expression and breakdown of the blood-retinal barrier.

    Science.gov (United States)

    Deeg, Cornelia A; Altmann, Frank; Hauck, Stefanie M; Schoeffmann, Stephanie; Amann, Barbara; Stangassinger, Manfred; Ueffing, Marius

    2007-05-01

    Spontaneous equine recurrent uveitis (ERU) is an incurable autoimmune disease affecting the eye. Identifying biological markers or pathways associated with this disease may allow the understanding of its pathogenesis at a molecular level. The vitreous is the body fluid closest to the disease-affected tissue and possibly also an effector of pathological processes relevant for ERU. Surgical removal of vitreous leads to cessation of relapses in spontaneous uveitis of both man and horse, therefore vitreous composites are likely to contribute to disease progression. Uveitic vitreous is likely to contain potential biomarkers in relatively undiluted quantities. With the goal to identify these markers, we systematically compared vitreous from healthy and disease-affected eyes by proteomic profiling. Nine differentially expressed proteins were identified, that are functionally related to immune response, inflammation, and maintenance of the blood-retinal barrier. One of these, pigment epithelium-derived factor, a protein involved in maintaining a proper blood-retina barrier as well as protecting from neoangiogenesis was additionally found to be down-regulated within uveitic retinal lesions whereas, conversely, vascular endothelial growth factor was found to be up-regulated at these sites. Together, these changes point to as of yet undiscovered biological pathways involved in the pathogenesis of this autoimmune disease.

  9. Detection of a novel stem cell probably involved in normal turnover of the lung airway epithelium.

    Science.gov (United States)

    Ortega-Martínez, Marta; Rodríguez-Flores, Laura E; de-la-Garza-González, Carlos; Ancer-Rodríguez, Jesús; Jaramillo-Rangel, Gilberto

    2015-11-01

    Regeneration of the lung airway epithelium after injury has been extensively studied. In contrast, analysis of its turnover in healthy adulthood has received little attention. In the classical view, this epithelium is maintained in the steady-state by the infrequent proliferation of basal or Clara cells. The intermediate filament protein nestin was initially identified as a marker for neural stem cells, but its expression has also been detected in other stem cells. Lungs from CD1 mice at the age of 2, 6, 12, 18 or 24 months were fixed in neutral-buffered formalin and paraffin-embedded. Nestin expression was examined by an immunohistochemical peroxidase-based method. Nestin-positive cells were detected in perivascular areas and in connective tissue that were in close proximity of the airway epithelium. Also, nestin-positive cells were found among the cells lining the airway epithelium. These findings suggest that nestin-positive stem cells circulate in the bloodstream, transmigrate through blood vessels and localize in the lung airway epithelium to participate in its turnover. We previously reported the existence of similar cells able to differentiate into lung chondrocytes. Thus, the stem cell reported here might be a bone marrow-derived mesenchymal stem cell (BMDMSC) able to generate several types of lung tissues. In conclusion, our findings indicate that there exist a BMDMSC in healthy adulthood that participates in the turnover of the lung airway epithelium. These findings may improve our knowledge about the lung stem cell biology and also provide novel approaches to therapy for devastating pulmonary diseases.

  10. Rotating pigment cells exhibit an intrinsic chirality.

    Science.gov (United States)

    Yamanaka, Hiroaki; Kondo, Shigeru

    2015-01-01

    In multicellular organisms, cell properties, such as shape, size and function are important in morphogenesis and physiological functions. Recently, 'cellular chirality' has attracted attention as a cellular property because it can cause asymmetry in the bodies of animals. In recent in vitro studies, the left-right bias of cellular migration and of autonomous arrangement of cells under some specific culture conditions were discovered. However, it is difficult to identify the molecular mechanism underlying their intrinsic chirality because the left-right bias observed to date is subtle or is manifested in the stable orientation of cells. Here, we report that zebrafish (Danio rerio) melanophores exhibit clear cellular chirality by unidirectional counterclockwise rotational movement under isolated conditions without any special settings. The chirality is intrinsic to melanophores because the direction of the cellular rotation was not affected by the type of extracellular matrix. We further found that the cellular rotation was generated as a counter action of the clockwise movement of actin cytoskeleton. It suggested that the mechanism that directs actin cytoskeleton in the clockwise direction is pivotal for determining cellular chirality.

  11. Study and retina allotransplantation of porcine ciliary epithelium (CE)-derived cells

    NARCIS (Netherlands)

    Cogliati, Tiziana Paola

    2012-01-01

    This thesis reports the isolation, characterization and allotransplantation in porcine retina of ciliary epithelium (CE)-derived cells, also known as retinal stem cells (RSCs). The self-renewal capacity and differentiation potential of these cells in vitro and in vivo makes them candidate donors in

  12. 色素上皮衍生因子在肿瘤中的研究进展%The progression in the study of pigmented epithelium-derived factor in tumors

    Institute of Scientific and Technical Information of China (English)

    苏宏伟; 杨澄; 任慧文; 李宏伟

    2014-01-01

    色素上皮衍生因子(PEDF)作为丝氨酸蛋白酶抑制剂超家族成员,通过抑制内皮细胞的增殖和迁移、诱导相关的凋亡信号通路和增加肿瘤细胞分化程度,从而发挥抑制肿瘤发生、发展及其转移的生物学功能.研究表明,PEDF在骨骼的正常生理和病理过程发挥重要调节作用.PEDF为基础的免疫治疗方法可以成功的用于治疗骨肉瘤(OS),并极大抑制了OS的进展和控制肺部转移.%Pigmented epithelium-derived factor(PEDF),a member of the serine protease inhibitor family,could inhibit the occurrence,development and metastasis of tumors through controlling proliferation of endothelial cells,inducing apoptosis,and promoting the differentiation of tumor cells.Studies have showed that PEDF plays regulatory effects in physiological and pathological processes of the bone.PEDF-based immunotherapy could efficiently restrain the development of osteosarcoma (OS) and its lung metastusis.

  13. Repair of tracheal epithelium by basal cells after chlorine-induced injury

    Directory of Open Access Journals (Sweden)

    Musah Sadiatu

    2012-11-01

    Full Text Available Abstract Background Chlorine is a widely used toxic compound that is considered a chemical threat agent. Chlorine inhalation injures airway epithelial cells, leading to pulmonary abnormalities. Efficient repair of injured epithelium is necessary to restore normal lung structure and function. The objective of the current study was to characterize repair of the tracheal epithelium after acute chlorine injury. Methods C57BL/6 mice were exposed to chlorine and injected with 5-ethynyl-2′-deoxyuridine (EdU to label proliferating cells prior to sacrifice and collection of tracheas on days 2, 4, 7, and 10 after exposure. Airway repair and restoration of a differentiated epithelium were examined by co-localization of EdU labeling with markers for the three major tracheal epithelial cell types [keratin 5 (K5 and keratin 14 (K14 for basal cells, Clara cell secretory protein (CCSP for Clara cells, and acetylated tubulin (AcTub for ciliated cells]. Morphometric analysis was used to measure proliferation and restoration of a pseudostratified epithelium. Results Epithelial repair was fastest and most extensive in proximal trachea compared with middle and distal trachea. In unexposed mice, cell proliferation was minimal, all basal cells expressed K5, and K14-expressing basal cells were absent from most sections. Chlorine exposure resulted in the sloughing of Clara and ciliated cells from the tracheal epithelium. Two to four days after chlorine exposure, cell proliferation occurred in K5- and K14-expressing basal cells, and the number of K14 cells was dramatically increased. In the period of peak cell proliferation, few if any ciliated or Clara cells were detected in repairing trachea. Expression of ciliated and Clara cell markers was detected at later times (days 7–10, but cell proliferation was not detected in areas in which these differentiated markers were re-expressed. Fibrotic lesions were observed at days 7–10 primarily in distal trachea. Conclusion

  14. Human retinal pigment epithelial cell-induced apoptosis in activated T cells

    DEFF Research Database (Denmark)

    Jørgensen, A; Wiencke, A K; la Cour, M

    1998-01-01

    human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction...... of apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...... induced apoptosis in several activated T-cell populations and T-cell lines, including T-cell antigen receptor (TCR)-CD3-negative T-cell lines. In contrast, RPE cells induced little or no apoptosis in resting peripheral T cells. Major histocompatibility complex (MHC) class II monoclonal antibodies, which...

  15. Tyrosinase-Cre-Mediated Deletion of the Autophagy Gene Atg7 Leads to Accumulation of the RPE65 Variant M450 in the Retinal Pigment Epithelium of C57BL/6 Mice

    Science.gov (United States)

    Sukseree, Supawadee; Chen, Ying-Ting; Laggner, Maria; Gruber, Florian; Petit, Valérie; Nagelreiter, Ionela-Mariana; Mlitz, Veronika; Rossiter, Heidemarie; Pollreisz, Andreas; Schmidt-Erfurth, Ursula; Larue, Lionel; Tschachler, Erwin

    2016-01-01

    Targeted gene knockout mouse models have helped to identify roles of autophagy in many tissues. Here, we investigated the retinal pigment epithelium (RPE) of Atg7f/f Tyr-Cre mice (on a C57BL/6 background), in which Cre recombinase is expressed under the control of the tyrosinase promoter to delete the autophagy gene Atg7. In line with pigment cell-directed blockade of autophagy, the RPE and the melanocytes of the choroid showed strong accumulation of the autophagy adaptor and substrate, sequestosome 1 (Sqstm1)/p62, relative to the levels in control mice. Immunofluorescence and Western blot analysis demonstrated that the RPE, but not the choroid melanocytes, of Atg7f/f Tyr-Cre mice also had strongly increased levels of retinoid isomerohydrolase RPE65, a pivotal enzyme for the maintenance of visual perception. In contrast to Sqstm1, genes involved in retinal regeneration, i.e. Lrat, Rdh5, Rgr, and Rpe65, were expressed at higher mRNA levels. Sequencing of the Rpe65 gene showed that Atg7f/f and Atg7f/f Tyr-Cre mice carry a point mutation (L450M) that is characteristic for the C57BL/6 mouse strain and reportedly causes enhanced degradation of the RPE65 protein by an as-yet unknown mechanism. These results suggest that the increased abundance of RPE65 M450 in the RPE of Atg7f/f Tyr-Cre mice is, at least partly, mediated by upregulation of Rpe65 transcription; however, our data are also compatible with the hypothesis that the RPE65 M450 protein is degraded by Atg7-dependent autophagy in Atg7f/f mice. Further studies in mice of different genetic backgrounds are necessary to determine the relative contributions of these mechanisms. PMID:27537685

  16. Hemosiderotic clear-cell acanthoma: A pigmented mimicker

    Directory of Open Access Journals (Sweden)

    Leonardo Bugatti

    2011-01-01

    Full Text Available The authors report on a case of a 65-year-old man with pigmented clear-cell acanthoma located on the right thigh. Dermoscopy disclosed a peculiar picture consisting of diffuse black pigmentation with a superficial greyish veil in the central portion, dotted-to-globular dark red-black structures mainly located at the periphery with a homogenous regular reticular arrangement; peripheral translucid desquamation. Dermoscopic features are correlated with the histology, where hemosiderin deposits present in a sheet-like arrangement in the perivascular papillary dermis and in a band-like disposition in the reticular dermis at the base of the lesion can account for the pigmented picture. The lesion arose on a trauma-prone skin site; thus the authors believe that traumatic irritation may be responsible for the clinical and dermoscopic pictures, giving rise to a reaction similar in a way to the Auspitz′s sign provocated by trauma for psoriasis. Red blood cells extravasation from extremely superficialized capillaries may have led to hemosiderin deposition in the papillary and the reticular dermis.

  17. Identification of an Alternative Splicing Product of the Otx2 Gene Expressed in the Neural Retina and Retinal Pigmented Epithelial Cells.

    Science.gov (United States)

    Kole, Christo; Berdugo, Naomi; Da Silva, Corinne; Aït-Ali, Najate; Millet-Puel, Géraldine; Pagan, Delphine; Blond, Frédéric; Poidevin, Laetitia; Ripp, Raymond; Fontaine, Valérie; Wincker, Patrick; Zack, Donald J; Sahel, José-Alain; Poch, Olivier; Léveillard, Thierry

    2016-01-01

    To investigate the complexity of alternative splicing in the retina, we sequenced and analyzed a total of 115,706 clones from normalized cDNA libraries from mouse neural retina (66,217) and rat retinal pigmented epithelium (49,489). Based upon clustering the cDNAs and mapping them with their respective genomes, the estimated numbers of genes were 9,134 for the mouse neural retina and 12,050 for the rat retinal pigmented epithelium libraries. This unique collection of retinal of messenger RNAs is maintained and accessible through a web-base server to the whole community of retinal biologists for further functional characterization. The analysis revealed 3,248 and 3,202 alternative splice events for mouse neural retina and rat retinal pigmented epithelium, respectively. We focused on transcription factors involved in vision. Among the six candidates suitable for functional analysis, we selected Otx2S, a novel variant of the Otx2 gene with a deletion within the homeodomain sequence. Otx2S is expressed in both the neural retina and retinal pigmented epithelium, and encodes a protein that is targeted to the nucleus. OTX2S exerts transdominant activity on the tyrosinase promoter when tested in the physiological environment of primary RPE cells. By overexpressing OTX2S in primary RPE cells using an adeno associated viral vector, we identified 10 genes whose expression is positively regulated by OTX2S. We find that OTX2S is able to bind to the chromatin at the promoter of the retinal dehydrogenase 10 (RDH10) gene.

  18. Identification of an Alternative Splicing Product of the Otx2 Gene Expressed in the Neural Retina and Retinal Pigmented Epithelial Cells

    Science.gov (United States)

    Kole, Christo; Berdugo, Naomi; Da Silva, Corinne; Aït-Ali, Najate; Millet-Puel, Géraldine; Pagan, Delphine; Blond, Frédéric; Poidevin, Laetitia; Ripp, Raymond; Fontaine, Valérie; Wincker, Patrick; Zack, Donald J.; Sahel, José-Alain; Poch, Olivier; Léveillard, Thierry

    2016-01-01

    To investigate the complexity of alternative splicing in the retina, we sequenced and analyzed a total of 115,706 clones from normalized cDNA libraries from mouse neural retina (66,217) and rat retinal pigmented epithelium (49,489). Based upon clustering the cDNAs and mapping them with their respective genomes, the estimated numbers of genes were 9,134 for the mouse neural retina and 12,050 for the rat retinal pigmented epithelium libraries. This unique collection of retinal of messenger RNAs is maintained and accessible through a web-base server to the whole community of retinal biologists for further functional characterization. The analysis revealed 3,248 and 3,202 alternative splice events for mouse neural retina and rat retinal pigmented epithelium, respectively. We focused on transcription factors involved in vision. Among the six candidates suitable for functional analysis, we selected Otx2S, a novel variant of the Otx2 gene with a deletion within the homeodomain sequence. Otx2S is expressed in both the neural retina and retinal pigmented epithelium, and encodes a protein that is targeted to the nucleus. OTX2S exerts transdominant activity on the tyrosinase promoter when tested in the physiological environment of primary RPE cells. By overexpressing OTX2S in primary RPE cells using an adeno associated viral vector, we identified 10 genes whose expression is positively regulated by OTX2S. We find that OTX2S is able to bind to the chromatin at the promoter of the retinal dehydrogenase 10 (RDH10) gene. PMID:26985665

  19. Cell-cell junctions: a target of acoustic overstimulation in the sensory epithelium of the cochlea

    Directory of Open Access Journals (Sweden)

    Zheng Guiliang

    2012-06-01

    Full Text Available Abstract Background Exposure to intense noise causes the excessive movement of the organ of Corti, stretching the organ and compromising sensory cell functions. We recently revealed changes in the transcriptional expression of multiple adhesion-related genes during the acute phases of cochlear damage, suggesting that the disruption of cell-cell junctions is an early event in the process of cochlear pathogenesis. However, the functional state of cell junctions in the sensory epithelium is not clear. Here, we employed graded dextran-FITC, a macromolecule tracer that is impermeable to the organ of Corti under physiological conditions, to evaluate the barrier function of cell junctions in normal and noise-traumatized cochlear sensory epithelia. Results Exposure to an impulse noise of 155 dB (peak sound pressure level caused a site-specific disruption in the intercellular junctions within the sensory epithelium of the chinchilla cochlea. The most vulnerable sites were the junctions among the Hensen cells and between the Hensen and Deiters cells within the outer zone of the sensory epithelium. The junction clefts that formed in the reticular lamina were permeable to 40 and 500 but not 2,000 kDa dextran-FITC macromolecules. Moreover, this study showed that the interruption of junction integrity occurred in the reticular lamina and also in the basilar membrane, a site that had been considered to be resistant to acoustic injury. Finally, our study revealed a general spatial correlation between the site of sensory cell damage and the site of junction disruption. However, the two events lacked a strict one-to-one correlation, suggesting that the disruption of cell-cell junctions is a contributing, but not the sole, factor for initiating acute sensory cell death. Conclusions Impulse noise causes the functional disruption of intercellular junctions in the sensory epithelium of the chinchilla cochlea. This disruption occurs at an early phase of cochlear

  20. Maintenance of sweat glands by stem cells located in the acral epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Ohe, Shuichi [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Department of Dermatology, Kansai Medical University, Osaka 573-1010 (Japan); Tanaka, Toshihiro [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Third Department of Internal Medicine, Kansai Medical University, Osaka 573-1010 (Japan); Yanai, Hirotsugu [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Department of Surgery, Kansai Medical University, Osaka 573-1010 (Japan); Komai, Yoshihiro [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Department of Urology and Andrology, Kansai Medical University, Osaka 573-1010 (Japan); Omachi, Taichi [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Department of Pediatrics, Kansai Medical University, Osaka 573-1010 (Japan); Kanno, Shohei; Tanaka, Kiyomichi; Ishigaki, Kazuhiko; Saiga, Kazuho [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Nakamura, Naohiro [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Third Department of Internal Medicine, Kansai Medical University, Osaka 573-1010 (Japan); Ohsugi, Haruyuki [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Department of Urology and Andrology, Kansai Medical University, Osaka 573-1010 (Japan); Tokuyama, Yoko; Atsumi, Naho; Hisha, Hiroko; Yoshida, Naoko; Kumano, Keiki [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan); Yamazaki, Fumikazu; Okamoto, Hiroyuki [Department of Dermatology, Kansai Medical University, Osaka 573-1010 (Japan); Ueno, Hiroo, E-mail: hueno@hirakata.kmu.ac.jp [Department of Stem Cell Pathology, Kansai Medical University, Osaka 573-1010 (Japan)

    2015-10-23

    The skin is responsible for a variety of physiological functions and is critical for wound healing and repair. Therefore, the regenerative capacity of the skin is important. However, stem cells responsible for maintaining the acral epithelium had not previously been identified. In this study, we identified the specific stem cells in the acral epithelium that participate in the long-term maintenance of sweat glands, ducts, and interadnexal epidermis and that facilitate the regeneration of these structures following injury. Lgr6-positive cells and Bmi1-positive cells were found to function as long-term multipotent stem cells that maintained the entire eccrine unit and the interadnexal epidermis. However, while Lgr6-positive cells were rapidly cycled and constantly supplied differentiated cells, Bmi1-positive cells were slow to cycle and occasionally entered the cell cycle under physiological conditions. Upon irradiation-induced injury, Bmi1-positive cells rapidly proliferated and regenerated injured epithelial tissue. Therefore, Bmi1-positive stem cells served as reservoir stem cells. Lgr5-positive cells were rapidly cycled and maintained only sweat glands; therefore, we concluded that these cells functioned as lineage-restricted progenitors. Taken together, our data demonstrated the identification of stem cells that maintained the entire acral epithelium and supported the different roles of three cellular classes. - Highlights: • The acral epithelium have two types of stem cells. • Lgr6-positive cells are rapid-cycling, short-term stem cells. • Bmi1-positive cells are slow-cycling stem cells that act as reserver stem cells. • Lgr5 may be a useful sweat gland marker in mice.

  1. Cavitary Lung Cancer Lined with Normal Bronchial Epithelium and Cancer Cells

    OpenAIRE

    Goto, Taichiro; Maeshima, Arafumi; Oyamada, Yoshitaka; Kato, Ryoichi

    2011-01-01

    Reports of cavitary lung cancer are not uncommon, and the cavity generally contains either dilated bronchi or cancer cells. Recently, we encountered a surgical case of cavitary lung cancer whose cavity tended to enlarge during long-term follow-up, and was found to be lined with normal bronchial epithelium and adenocarcinoma cells.

  2. Multi-resolution cell orientation congruence descriptors for epithelium segmentation in endometrial histology images.

    Science.gov (United States)

    Li, Guannan; Raza, Shan E Ahmed; Rajpoot, Nasir M

    2017-04-01

    It has been recently shown that recurrent miscarriage can be caused by abnormally high ratio of number of uterine natural killer (UNK) cells to the number of stromal cells in human female uterus lining. Due to high workload, the counting of UNK and stromal cells needs to be automated using computer algorithms. However, stromal cells are very similar in appearance to epithelial cells which must be excluded in the counting process. To exclude the epithelial cells from the counting process it is necessary to identify epithelial regions. There are two types of epithelial layers that can be encountered in the endometrium: luminal epithelium and glandular epithelium. To the best of our knowledge, there is no existing method that addresses the segmentation of both types of epithelium simultaneously in endometrial histology images. In this paper, we propose a multi-resolution Cell Orientation Congruence (COCo) descriptor which exploits the fact that neighbouring epithelial cells exhibit similarity in terms of their orientations. Our experimental results show that the proposed descriptors yield accurate results in simultaneously segmenting both luminal and glandular epithelium.

  3. Wnt信号通路在视网膜色素上皮发育中的作用%The roles of Wnt signaling pathway in the development of retinal pigment epithelium

    Institute of Scientific and Technical Information of China (English)

    殷秋菊; 赵娉婷; 杨春波; 李筱荣

    2014-01-01

    Wnt signaling plays important roles in embryonic development and cell differentiation, especially during central nervous system (CNS) development. At the early stage of eye development, retinal pigment epithelium (RPE) in the dorsal optic vesicle shows intensive Wnt/β-catenin signaling activity, which is critical for the development of neural retina and RPE. This review focuses on recent advances in the fields of Wnt signaling pathway, Wnt protein family and the relationship between Wnt signaling and RPE development and differentiation.%Wnt(wingless-type MMTV integration site family members)信号通路与细胞的发育分化密切相关,尤其对动物胚胎期中枢神经系统的发育至关重要。在眼的早期发育中,视泡背部视网膜色素上皮细胞(RPE)Wnt/βcatenin信号通路高度活跃,对神经视网膜及RPE的发育调控起重要作用。本文结合目前该领域研究进展,综合评述Wnt信号通路、Wnt蛋白家族以及Wnt信号通路与RPE发育的关系。

  4. Maintenance of sweat glands by stem cells located in the acral epithelium.

    Science.gov (United States)

    Ohe, Shuichi; Tanaka, Toshihiro; Yanai, Hirotsugu; Komai, Yoshihiro; Omachi, Taichi; Kanno, Shohei; Tanaka, Kiyomichi; Ishigaki, Kazuhiko; Saiga, Kazuho; Nakamura, Naohiro; Ohsugi, Haruyuki; Tokuyama, Yoko; Atsumi, Naho; Hisha, Hiroko; Yoshida, Naoko; Kumano, Keiki; Yamazaki, Fumikazu; Okamoto, Hiroyuki; Ueno, Hiroo

    2015-10-23

    The skin is responsible for a variety of physiological functions and is critical for wound healing and repair. Therefore, the regenerative capacity of the skin is important. However, stem cells responsible for maintaining the acral epithelium had not previously been identified. In this study, we identified the specific stem cells in the acral epithelium that participate in the long-term maintenance of sweat glands, ducts, and interadnexal epidermis and that facilitate the regeneration of these structures following injury. Lgr6-positive cells and Bmi1-positive cells were found to function as long-term multipotent stem cells that maintained the entire eccrine unit and the interadnexal epidermis. However, while Lgr6-positive cells were rapidly cycled and constantly supplied differentiated cells, Bmi1-positive cells were slow to cycle and occasionally entered the cell cycle under physiological conditions. Upon irradiation-induced injury, Bmi1-positive cells rapidly proliferated and regenerated injured epithelial tissue. Therefore, Bmi1-positive stem cells served as reservoir stem cells. Lgr5-positive cells were rapidly cycled and maintained only sweat glands; therefore, we concluded that these cells functioned as lineage-restricted progenitors. Taken together, our data demonstrated the identification of stem cells that maintained the entire acral epithelium and supported the different roles of three cellular classes.

  5. Apico-basal forces exerted by apoptotic cells drive epithelium folding.

    Science.gov (United States)

    Monier, Bruno; Gettings, Melanie; Gay, Guillaume; Mangeat, Thomas; Schott, Sonia; Guarner, Ana; Suzanne, Magali

    2015-02-12

    Epithelium folding is a basic morphogenetic event that is essential in transforming simple two-dimensional epithelial sheets into three-dimensional structures in both vertebrates and invertebrates. Folding has been shown to rely on apical constriction. The resulting cell-shape changes depend either on adherens junction basal shift or on a redistribution of myosin II, which could be driven by mechanical signals. Yet the initial cellular mechanisms that trigger and coordinate cell remodelling remain largely unknown. Here we unravel the active role of apoptotic cells in initiating morphogenesis, thus revealing a novel mechanism of epithelium folding. We show that, in a live developing tissue, apoptotic cells exert a transient pulling force upon the apical surface of the epithelium through a highly dynamic apico-basal myosin II cable. The apoptotic cells then induce a non-autonomous increase in tissue tension together with cortical myosin II apical stabilization in the surrounding tissue, eventually resulting in epithelium folding. Together our results, supported by a theoretical biophysical three-dimensional model, identify an apoptotic myosin-II-dependent signal as the initial signal leading to cell reorganization and tissue folding. This work further reveals that, far from being passively eliminated as generally assumed (for example, during digit individualization), apoptotic cells actively influence their surroundings and trigger tissue remodelling through regulation of tissue tension.

  6. Subretinal Pigment Epithelial Deposition of Drusen Components Including Hydroxyapatite in a Primary Cell Culture Model

    Science.gov (United States)

    Pilgrim, Matthew G.; Lengyel, Imre; Lanzirotti, Antonio; Newville, Matt; Fearn, Sarah; Emri, Eszter; Knowles, Jonathan C.; Messinger, Jeffrey D.; Read, Russell W.; Guidry, Clyde; Curcio, Christine A.

    2017-01-01

    Purpose Extracellular deposits containing hydroxyapatite, lipids, proteins, and trace metals that form between the basal lamina of the RPE and the inner collagenous layer of Bruch's membrane are hallmarks of early AMD. We examined whether cultured RPE cells could produce extracellular deposits containing all of these molecular components. Methods Retinal pigment epithelium cells isolated from freshly enucleated porcine eyes were cultured on Transwell membranes for up to 6 months. Deposit composition and structure were characterized using light, fluorescence, and electron microscopy; synchrotron x-ray diffraction and x-ray fluorescence; secondary ion mass spectroscopy; and immunohistochemistry. Results Apparently functional primary RPE cells, when cultured on 10-μm-thick inserts with 0.4-μm-diameter pores, can produce sub-RPE deposits that contain hydroxyapatite, lipids, proteins, and trace elements, without outer segment supplementation, by 12 weeks. Conclusions The data suggest that sub-RPE deposit formation is initiated, and probably regulated, by the RPE, as well as the loss of permeability of the Bruch's membrane and choriocapillaris complex associated with age and early AMD. This cell culture model of early AMD lesions provides a novel system for testing new therapeutic interventions against sub-RPE deposit formation, an event occurring well in advance of the onset of vision loss. PMID:28146236

  7. Chronic intermittent hypoxia increases encoding pigment epithelium-derived factor gene expression, although not that of the protein itself, in the temporal cortex of rats,

    Directory of Open Access Journals (Sweden)

    Guilherme Silva Julian

    2015-02-01

    Full Text Available Objective: Obstructive sleep apnea syndrome is mainly characterized by intermittent hypoxia (IH during sleep, being associated with several complications. Exposure to IH is the most widely used animal model of sleep apnea, short-term IH exposure resulting in cognitive and neuronal impairment. Pigment epithelium-derived factor (PEDF is a hypoxia-sensitive factor acting as a neurotrophic, neuroprotective, and antiangiogenic agent. Our study analyzed performance on learning and cognitive tasks, as well as PEDF gene expression and PEDF protein expression in specific brain structures, in rats exposed to long-term IH. Methods: Male Wistar rats were exposed to IH (oxygen concentrations of 21-5% for 6 weeks-the chronic IH (CIH group-or normoxia for 6 weeks-the control group. After CIH exposure, a group of rats were allowed to recover under normoxic conditions for 2 weeks (the CIH+N group. All rats underwent the Morris water maze test for learning and memory, PEDF gene expression and PEDF protein expression in the hippocampus, frontal cortex, and temporal cortex being subsequently assessed. Results: The CIH and CIH+N groups showed increased PEDF gene expression in the temporal cortex, PEDF protein expression remaining unaltered. PEDF gene expression and PEDF protein expression remained unaltered in the frontal cortex and hippocampus. Long-term exposure to IH did not affect cognitive function. Conclusions: Long-term exposure to IH selectively increases PEDF gene expression at the transcriptional level, although only in the temporal cortex. This increase is probably a protective mechanism against IH-induced injury.

  8. Pigment epithelium-derived factor and diabetic nephropathy%色素上皮衍生因子与糖尿病肾病

    Institute of Scientific and Technical Information of China (English)

    李珍瑾; 李竞

    2008-01-01

    色素上皮衍生因子(PEDF)是一种高效、天然的血管增生抑制剂,具有神经营养保护、调节血管通透性和高效抑制血管生成等作用.近年来有研究表明,PEDF的减少与糖尿病肾病(DN)有密切关系,PEDF可抑制转化生长因子-β1(TGF-β1)和结缔组织生长因子(CTGF)的表达,抑制细胞外基质(ECM)的聚积,提示其具有抗纤维化活性,同时可通过调节肾脏脉管系统发展和维持肾自身稳态来发挥对DN的保护作用.PEDF可抑制DN的发生、发展,可能成为DN治疗的一种新方向.%Pigment epithelium-derived factor(PEDF)is an efficient natural angiogenic inhibitor that can protect neuronal nutrition,regulate vascular permeability and antiangiogenie activity.Recent studies show that the decrease of PEDF levels may be closely involved in diabetic nephmpathy(DN).PEDF inhibits the expression of TGF-β1 and CTGF,and suppresses the production of ECM protein in diabetic kidney,suggesting it has antifibrogenic activity.Meanwhile,PEDF phys a role in regulating the development of renal vasculature and maintenance of renal homeostasis,and may be responsible for its salutary effect in DN.PEDF can inhibit the occurrence and development of DN,and may become a new target for the treatment of DN.

  9. Augmented expression and secretion of adipose-derived pigment epithelium-derived factor does not alter local angiogenesis or contribute to the development of systemic metabolic derangements.

    Science.gov (United States)

    Lakeland, Thomas V; Borg, Melissa L; Matzaris, Maria; Abdelkader, Amany; Evans, Roger G; Watt, Matthew J

    2014-06-15

    Impaired coupling of adipose tissue expansion and vascularization is proposed to lead to adipocyte hypoxia and inflammation, which in turn contributes to systemic metabolic derangements. Pigment epithelium-derived factor (PEDF) is a powerful antiangiogenic factor that is secreted by adipocytes, elevated in obesity, and implicated in the development of insulin resistance. We explored the angiogenic and metabolic role of adipose-derived PEDF through in vivo studies of mice with overexpression of PEDF in adipocytes (PEDF-aP2). PEDF expression in white adipocytes and PEDF secretion from adipose tissue was increased in transgenic mice, but circulating levels of PEDF were not increased. Overexpression of PEDF did not alter vascularization, the partial pressure of O2, cellular hypoxia, or gene expression of inflammatory markers in adipose tissue. Energy expenditure and metabolic substrate utilization, body mass, and adiposity were not altered in PEDF-aP2 mice. Whole body glycemic control was normal as assessed by glucose and insulin tolerance tests, and adipocyte-specific glucose uptake was unaffected by PEDF overexpression. Adipocyte lipolysis was increased in PEDF-aP2 mice and associated with increased adipose triglyceride lipase and decreased perilipin 1 expression. Experiments conducted in mice rendered obese by high-fat feeding showed no differences between PEDF-aP2 and wild-type mice for body mass, adiposity, whole body energy expenditure, glucose tolerance, or adipose tissue oxygenation. Together, these data indicate that adipocyte-generated PEDF enhances lipolysis but question the role of PEDF as a major antiangiogenic or proinflammatory mediator in adipose tissue in vivo. Copyright © 2014 the American Physiological Society.

  10. Increased Abundance of M Cells in the Gut Epithelium Dramatically Enhances Oral Prion Disease Susceptibility.

    Science.gov (United States)

    Donaldson, David S; Sehgal, Anuj; Rios, Daniel; Williams, Ifor R; Mabbott, Neil A

    2016-12-01

    Many natural prion diseases of humans and animals are considered to be acquired through oral consumption of contaminated food or pasture. Determining the route by which prions establish host infection will identify the important factors that influence oral prion disease susceptibility and to which intervention strategies can be developed. After exposure, the early accumulation and replication of prions within small intestinal Peyer's patches is essential for the efficient spread of disease to the brain. To replicate within Peyer's patches, the prions must first cross the gut epithelium. M cells are specialised epithelial cells within the epithelia covering Peyer's patches that transcytose particulate antigens and microorganisms. M cell-development is dependent upon RANKL-RANK-signalling, and mice in which RANK is deleted only in the gut epithelium completely lack M cells. In the specific absence of M cells in these mice, the accumulation of prions within Peyer's patches and the spread of disease to the brain was blocked, demonstrating a critical role for M cells in the initial transfer of prions across the gut epithelium in order to establish host infection. Since pathogens, inflammatory stimuli and aging can modify M cell-density in the gut, these factors may also influence oral prion disease susceptibility. Mice were therefore treated with RANKL to enhance M cell density in the gut. We show that prion uptake from the gut lumen was enhanced in RANKL-treated mice, resulting in shortened survival times and increased disease susceptibility, equivalent to a 10-fold higher infectious titre of prions. Together these data demonstrate that M cells are the critical gatekeepers of oral prion infection, whose density in the gut epithelium directly limits or enhances disease susceptibility. Our data suggest that factors which alter M cell-density in the gut epithelium may be important risk factors which influence host susceptibility to orally acquired prion diseases.

  11. In vitro culture of embryonic mouse intestinal epithelium: cell differentiation and introduction of reporter genes

    Directory of Open Access Journals (Sweden)

    Hornsey Mark A

    2006-05-01

    Full Text Available Abstract Background Study of the normal development of the intestinal epithelium has been hampered by a lack of suitable model systems, in particular ones that enable the introduction of exogenous genes. Production of such a system would advance our understanding of normal epithelial development and help to shed light on the pathogenesis of intestinal neoplasia. The criteria for a reliable culture system include the ability to perform real time observations and manipulations in vitro, the preparation of wholemounts for immunostaining and the potential for introducing genes. Results The new culture system involves growing mouse embryo intestinal explants on fibronectin-coated coverslips in basal Eagle's medium+20% fetal bovine serum. Initially the cultures maintain expression of the intestinal transcription factor Cdx2 together with columnar epithelial (cytokeratin 8 and mesenchymal (smooth muscle actin markers. Over a few days of culture, differentiation markers appear characteristic of absorptive epithelium (sucrase-isomaltase, goblet cells (Periodic Acid Schiff positive, enteroendocrine cells (chromogranin A and Paneth cells (lysozyme. Three different approaches were tested to express genes in the developing cultures: transfection, electroporation and adenoviral infection. All could introduce genes into the mesenchyme, but only to a small extent into the epithelium. However the efficiency of adenovirus infection can be greatly improved by a limited enzyme digestion, which makes accessible the lateral faces of cells bearing the Coxsackie and Adenovirus Receptor. This enables reliable delivery of genes into epithelial cells. Conclusion We describe a new in vitro culture system for the small intestine of the mouse embryo that recapitulates its normal development. The system both provides a model for studying normal development of the intestinal epithelium and also allows for the manipulation of gene expression. The explants can be cultured for up

  12. Structure and barrier properties of human embryonic stem cell-derived retinal pigment epithelial cells are affected by extracellular matrix protein coating.

    Science.gov (United States)

    Sorkio, Anni; Hongisto, Heidi; Kaarniranta, Kai; Uusitalo, Hannu; Juuti-Uusitalo, Kati; Skottman, Heli

    2014-02-01

    Extracellular matrix (ECM) interactions play a vital role in cell morphology, migration, proliferation, and differentiation of cells. We investigated the role of ECM proteins on the structure and function of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells during their differentiation and maturation from hESCs into RPE cells in adherent differentiation cultures on several human ECM proteins found in native human Bruch's membrane, namely, collagen I, collagen IV, laminin, fibronectin, and vitronectin, as well as on commercial substrates of xeno-free CELLstart™ and Matrigel™. Cell pigmentation, expression of RPE-specific proteins, fine structure, as well as the production of basal lamina by hESC-RPE on different protein coatings were evaluated after 140 days of differentiation. The integrity of hESC-RPE epithelium and barrier properties on different coatings were investigated by measuring transepithelial resistance. All coatings supported the differentiation of hESC-RPE cells as demonstrated by early onset of cell pigmentation and further maturation to RPE monolayers after enrichment. Mature RPE phenotype was verified by RPE-specific gene and protein expression, correct epithelial polarization, and phagocytic activity. Significant differences were found in the degree of RPE cell pigmentation and tightness of epithelial barrier between different coatings. Further, the thickness of self-assembled basal lamina and secretion of the key ECM proteins found in the basement membrane of the native RPE varied between hESC-RPE cultured on compared protein coatings. In conclusion, this study shows that the cell culture substrate has a major effect on the structure and basal lamina production during the differentiation and maturation of hESC-RPE potentially influencing the success of cell integrations and survival after cell transplantation.

  13. Effects of hypoxia on the expression of human retinal pigment epithelium cells cultured in vitro%缺氧对体外培养的人视网膜色素上皮细胞热休克蛋白47表达的影响

    Institute of Scientific and Technical Information of China (English)

    曾爱萍; 曾水清; 吕明良; 程扬

    2006-01-01

    目的:探讨缺氧对体外培养的人视网膜色素上皮(retinal pigment epitelium,RPE)细胞热休克蛋白47(heat shock protein 47,HSP47)表达的影响.方法:培养的人RPE细胞分为两组:缺氧组使用化学缺氧诱导剂CoCl2模拟RPE细胞缺氧环境来培养人RPE细胞,对照组置入正常环境中培养.采用半定量RT-PCR检测人RPE细胞中HSP47mRNA的表达,Western blot蛋白印迹分析检测人RPE细胞中蛋白水平.结果:缺氧组AHSP47/Aβ-actin比值为1.46±0.15与对照组比值0.94±0.13比较,差异有显著意义(P<0.05).同时缺氧组HSP47蛋白含量平均A值为728.03±38.15显著高于正常对照组平均A值571.47±26.95,差异有统计学意义(P<0.05).结论:HSP47在缺氧状态下异常高表达.

  14. Expression of the stem cell marker, SOX2, in ameloblastoma and dental epithelium.

    Science.gov (United States)

    Juuri, Emma; Isaksson, Sanna; Jussila, Maria; Heikinheimo, Kristiina; Thesleff, Irma

    2013-12-01

    Ameloblastomas are locally invasive odontogenic tumors that exhibit a high rate of recurrence and often associate with the third molars. They are suggested to originate from dental epithelium because the tumor cells resemble epithelial cells of developing teeth. Expression of the transcription factor SOX2 has been previously localized in epithelial stem and progenitor cells in developing teeth as well as in various tumors. Here, we show that SOX2 is expressed in the epithelial cells of follicular and plexiform ameloblastomas. SOX2 was localized in the dental lamina of developing human primary molars. It was also expressed in the fragmented dental lamina associated with the third molars and in the epithelium budding from its posterior aspect in mice. However, no SOX2 expression was detected in either Hertwig's epithelial root sheath directing the formation of roots or in the epithelial cell rests of Malassez covering the completed roots. SOX2 was associated with supernumerary tooth formation in odontoma-like tumors induced by Wnt signal activation in mice. We propose that SOX2 functions in maintaining the progenitor state of epithelium in ameloblastomas and that ameloblastomas may originate from SOX2-expressing dental lamina epithelium.

  15. Human retinal pigment epithelial cell-induced apoptosis in activated T cells

    DEFF Research Database (Denmark)

    Jørgensen, A; Wiencke, A K; la Cour, M;

    1998-01-01

    PURPOSE: The immune privilege of the eye has been thought to be dependent on physical barriers and absence of lymphatic vessels. However, the immune privilege may also involve active immunologic processes, as recent studies have indicated. The purpose of the present study was to investigate whether...... human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction...... of apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...

  16. Pigment cell interactions and differential xanthophore recruitment underlying zebrafish stripe reiteration and Danio pattern evolution.

    Science.gov (United States)

    Patterson, Larissa B; Bain, Emily J; Parichy, David M

    2014-11-06

    Fishes have diverse pigment patterns, yet mechanisms of pattern evolution remain poorly understood. In zebrafish, Danio rerio, pigment-cell autonomous interactions generate dark stripes of melanophores that alternate with light interstripes of xanthophores and iridophores. Here, we identify mechanisms underlying the evolution of a uniform pattern in D. albolineatus in which all three pigment cell classes are intermingled. We show that in this species xanthophores differentiate precociously over a wider area, and that cis regulatory evolution has increased expression of xanthogenic Colony Stimulating Factor-1 (Csf1). Expressing Csf1 similarly in D. rerio has cascading effects, driving the intermingling of all three pigment cell classes and resulting in the loss of stripes, as in D. albolineatus. Our results identify novel mechanisms of pattern development and illustrate how pattern diversity can be generated when a core network of pigment-cell autonomous interactions is coupled with changes in pigment cell differentiation.

  17. Mechanism of riboflavin uptake by cultured human retinal pigment epithelial ARPE-19 cells: possible regulation by an intracellular Ca2+-calmodulin-mediated pathway

    OpenAIRE

    Said, Hamid M.; Wang, S.L.; Ma, T Y

    2005-01-01

    In mammalian cells (including those of the ocular system), the water-soluble vitamin B-2 (riboflavin, RF) assumes an essential role in a variety of metabolic reactions and is critical for normal cellular functions, growth and development. Cells of the human retinal pigment epithelium (hRPE) play an important role in providing a sufficient supply of RF to the retina, but nothing is known about the mechanism of the vitamin uptake by these cells and its regulation. Our aim in the present study w...

  18. Anchor cell invasion into the vulval epithelium in C. elegans.

    Science.gov (United States)

    Sherwood, David R; Sternberg, Paul W

    2003-07-01

    An understanding of cell-invasive behavior has been limited by the lack of in vivo models where this activity can be clearly visualized and manipulated. We show that a single cell in the Caenorhabditis elegans gonad, the anchor cell (AC), initiates uterine-vulval contact through a cell invasion event. Using genetic analysis, laser ablations, and cell-specific markers, we demonstrate that AC invasion is predominantly stimulated by the 1 degrees vulval lineage cells, which generate a diffusible signal that promotes AC invasive behavior toward these cells and further targets invasive processes between the two central 1 degrees vulval lineage cells. We also show that AC invasion is regulated by the AC response to this cue, as well as a vulval-independent mechanism that weakly drives invasion. These studies dissect the regulatory mechanisms that underlie a simple cell-invasive behavior in vivo, and introduce AC invasion as a model for understanding key checkpoints controlling cell invasion.

  19. Unjamming and cell shape in the asthmatic airway epithelium

    Science.gov (United States)

    Park, Jin-Ah; Kim, Jae Hun; Bi, Dapeng; Mitchel, Jennifer A.; Qazvini, Nader Taheri; Tantisira, Kelan; Park, Chan Young; McGill, Maureen; Kim, Sae-Hoon; Gweon, Bomi; Notbohm, Jacob; Steward, Robert, Jr.; Burger, Stephanie; Randell, Scott H.; Kho, Alvin T.; Tambe, Dhananjay T.; Hardin, Corey; Shore, Stephanie A.; Israel, Elliot; Weitz, David A.; Tschumperlin, Daniel J.; Henske, Elizabeth P.; Weiss, Scott T.; Manning, M. Lisa; Butler, James P.; Drazen, Jeffrey M.; Fredberg, Jeffrey J.

    2015-10-01

    From coffee beans flowing in a chute to cells remodelling in a living tissue, a wide variety of close-packed collective systems--both inert and living--have the potential to jam. The collective can sometimes flow like a fluid or jam and rigidify like a solid. The unjammed-to-jammed transition remains poorly understood, however, and structural properties characterizing these phases remain unknown. Using primary human bronchial epithelial cells, we show that the jamming transition in asthma is linked to cell shape, thus establishing in that system a structural criterion for cell jamming. Surprisingly, the collapse of critical scaling predicts a counter-intuitive relationship between jamming, cell shape and cell-cell adhesive stresses that is borne out by direct experimental observations. Cell shape thus provides a rigorous structural signature for classification and investigation of bronchial epithelial layer jamming in asthma, and potentially in any process in disease or development in which epithelial dynamics play a prominent role.

  20. Remodeling of bovine oviductal epithelium by mitosis of secretory cells.

    Science.gov (United States)

    Ito, Sayaka; Kobayashi, Yoshihiko; Yamamoto, Yuki; Kimura, Koji; Okuda, Kiyoshi

    2016-11-01

    Two types of oviductal epithelial cells, secretory and ciliated, play crucial roles in the first days after fertilization in mammals. Secretory cells produce various molecules promoting embryo development, while ciliated cells facilitate transport of oocytes and zygotes by ciliary beating. The proportions of the two cell types change during the estrous cycle. The proportion of ciliated cells on the oviductal luminal surface is abundant at the follicular phase, whereas the proportion of secretory cells gradually increases with the formation of the corpus luteum. In the present study, we hypothesize that the proportions of ciliated and secretory epithelial cells are regulated by mitosis. The proportion of the cells being positive for FOXJ1 (a ciliated cell marker) or Ki67 (a mitosis marker) in epithelial cells during the estrous cycle were immunohistochemically examined. Ki67 and FOXJ1 or PAX8 (a secretory cell marker), were double-stained to clarify which types of epithelial cells undergo mitosis. In the ampulla, the percentage of FOXJ1-positive cells was highest at the day of ovulation (Day 0) and decreased by about 50 % by Days 8-12, while in the isthmus it did not change during the estrous cycle. The proportion of Ki67-positive cells was highest at around the time of ovulation in both the ampulla and isthmus. All the Ki67-positive cells were PAX8-positive and FOXJ1-negative in both the ampulla and isthmus. These findings suggest that epithelial remodeling, which is regulated by differentiation and/or proliferation of secretory cells of the oviduct, provides the optimal environment for gamete transport, fertilization and embryonic development.

  1. TR146 cells grown on filters as a model of human buccal epithelium

    DEFF Research Database (Denmark)

    Mørck Nielsen, H; Rømer Rassing, M; Nielsen, Hanne Mørck

    2000-01-01

    The objective of the present study was to characterise the TR146 cell culture model as an in vitro model of human buccal mucosa with respect to the enzyme activity in the tissues. For this purpose, the contents of aminopeptidase, carboxypeptidase and esterase in homogenate supernatants of the TR146...... cell culture model, and human and porcine buccal epithelium were compared. The esterase activity in the intact cell culture model and in the porcine buccal mucosa was compared. Further, the TR146 cell culture model was used to study the permeability rate and metabolism of leu-enkephalin. The activity...... of the three enzymes in the TR146 homogenate supernatants was in the same range as the activity in homogenate supernatants of human buccal epithelium. In the TR146 cell culture model, the activity of aminopeptidase (13.70+/-2.10 nmol/min per mg protein) was approx. four times the activity of carboxypeptidase...

  2. Epithelial Cell Damage Activates Bactericidal/Permeability Increasing-Protein (BPI Expression in Intestinal Epithelium

    Directory of Open Access Journals (Sweden)

    Arjun Balakrishnan

    2017-08-01

    Full Text Available As the first line of defense against invading pathogen, intestinal epithelium produces various antimicrobial proteins (AMP that help in clearance of pathogen. Bactericidal/permeability-increasing protein (BPI is a 55 kDa AMP that is expressed in intestinal epithelium. Dysregulation of BPI in intestinal epithelium is associated with various inflammatory diseases like Crohn’s Disease, Ulcerative colitis, and Infectious enteritis’s. In this paper, we report a direct correlation between intestinal damage and BPI expression. In Caco-2 cells, we see a significant increase in BPI levels upon membrane damage mediated by S. aureus infection and pore-forming toxins (Streptolysin and Listeriolysin. Cells detect changes in potassium level as a Danger-associated molecular pattern associated with cell damage and induce BPI expression in a p38 dependent manner. These results are further supported by in vivo findings that the BPI expression in murine intestinal epithelium is induced upon infection with bacteria which cause intestinal damage (Salmonella Typhimurium and Shigella flexneri whereas mutants that do not cause intestinal damage (STM ΔfliC and STM ΔinvC did not induce BPI expression. Our results suggest that epithelial damage associated with infection act as a signal to induce BPI expression.

  3. Differentiation of embryonic stem cells into corneal epithelium

    Institute of Scientific and Technical Information of China (English)

    WANG Zhichong; LIU Jingbo; GE Jian; HUANG Bing; GAO Qianying; LIU Bingqian; WANG Linghua; YU Ling; FAN Zhigang; LU Xiaoming

    2005-01-01

    Our project was to determine whether embryonic stem (ES) cells could be induced to differentiate into corneal epithelia by superficial corneoscleral limbal stroma. To achieve this goal, ES-GFP cell line D3 was pre-induced by retinoic acid (RA). The pre-induced cells were seeded on deepithelialized superficial corneoscleral slices (SCSS) to form a monolayer, and divided into three groups. Group 1 was cultured and passaged in vitro for direct detection. Group 2 was exposed to air-liquid interfaces for 10 days and implanted into the subcutaneous layer of nude mice for 2 weeks for further induction in vivo. Group 3 was cultured in vitro without any inducing factors for control. There were no teratomas found in nude mice which were implanted with differentiated ES cells after two weeks. The differentiated cells showed an appearance of epithelia both in vitro and in vivo. Expression of CK3, P63 and PCNA was detected by immunohistochemical staining in the differentiated cells in group 1 and 2. Microvillis and zonula occludens were observed on the surface of the differentiated cells under an electron microscope. In the control group, ES cells differentiated freely without any inducing factors. Most cells were shed and formed a neuronal dendrite-like structure, and a minority of cells appeared polymorphic. These results demonstrate that ES cells can differentiate into corneal epithelia on the surface of SCSS under the controlled condition. Differentiated ES cells could be used as epithelial seeding cells for the reconstruction of ocular surface and corneal tissue engineering in the future.

  4. Neuropilin 1 Receptor Is Up-Regulated in Dysplastic Epithelium and Oral Squamous Cell Carcinoma.

    Science.gov (United States)

    Shahrabi-Farahani, Shokoufeh; Gallottini, Marina; Martins, Fabiana; Li, Erik; Mudge, Dayna R; Nakayama, Hironao; Hida, Kyoko; Panigrahy, Dipak; D'Amore, Patricia A; Bielenberg, Diane R

    2016-04-01

    Neuropilins are receptors for disparate ligands, including proangiogenic factors such as vascular endothelial growth factor and inhibitory class 3 semaphorin (SEMA3) family members. Differentiated cells in skin epithelium and cutaneous squamous cell carcinoma highly express the neuropilin-1 (NRP1) receptor. We examined the expression of NRP1 in human and mouse oral mucosa. NRP1 was significantly up-regulated in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC). NRP1 receptor localized to the outer suprabasal epithelial layers in normal tongue, an expression pattern similar to the normal skin epidermis. However, dysplastic tongue epithelium and OSCC up-regulated NRP1 in basal and proliferating epithelial layers, a profile unseen in cutaneous squamous cell carcinoma. NRP1 up-regulation is observed in a mouse carcinogen-induced OSCC model and in human tongue OSCC biopsies. Human OSCC cell lines express NRP1 protein in vitro and in mouse tongue xenografts. Sites of capillary infiltration into orthotopic OSCC tumors correlate with high NRP1 expression. HSC3 xenografts, which express the highest NRP1 levels of the cell lines examined, showed massive intratumoral lymphangiogenesis. SEMA3A inhibited OSCC cell migration, suggesting that the NRP1 receptor was bioactive in OSCC. In conclusion, NRP1 is regulated in the oral epithelium and is selectively up-regulated during epithelial dysplasia. NRP1 may function as a reservoir to sequester proangiogenic ligands within the neoplastic compartment, thereby recruiting neovessels toward tumor cells.

  5. Neuropilin 1 Receptor Is Up-Regulated in Dysplastic Epithelium and Oral Squamous Cell Carcinoma

    Science.gov (United States)

    Shahrabi-Farahani, Shokoufeh; Gallottini, Marina; Martins, Fabiana; Li, Erik; Mudge, Dayna R.; Nakayama, Hironao; Hida, Kyoko; Panigrahy, Dipak; D'Amore, Patricia A.; Bielenberg, Diane R.

    2017-01-01

    Neuropilins are receptors for disparate ligands, including proangiogenic factors such as vascular endothelial growth factor and inhibitory class 3 semaphorin (SEMA3) family members. Differentiated cells in skin epithelium and cutaneous squamous cell carcinoma highly express the neuropilin-1 (NRP1) receptor. We examined the expression of NRP1 in human and mouse oral mucosa. NRP1 was significantly up-regulated in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC). NRP1 receptor localized to the outer suprabasal epithelial layers in normal tongue, an expression pattern similar to the normal skin epidermis. However, dysplastic tongue epithelium and OSCC up-regulated NRP1 in basal and proliferating epithelial layers, a profile unseen in cutaneous squamous cell carcinoma. NRP1 up-regulation is observed in a mouse carcinogen-induced OSCC model and in human tongue OSCC biopsies. Human OSCC cell lines express NRP1 protein in vitro and in mouse tongue xenografts. Sites of capillary infiltration into orthotopic OSCC tumors correlate with high NRP1 expression. HSC3 xenografts, which express the highest NRP1 levels of the cell lines examined, showed massive intratumoral lymphangiogenesis. SEMA3A inhibited OSCC cell migration, suggesting that the NRP1 receptor was bioactive in OSCC. In conclusion, NRP1 is regulated in the oral epithelium and is selectively up-regulated during epithelial dysplasia. NRP1 may function as a reservoir to sequester proangiogenic ligands within the neoplastic compartment, thereby recruiting neovessels toward tumor cells. PMID:26877262

  6. A method for the isolation and culture of adult rat retinal pigment epithelial (RPE cells to study retinal diseases

    Directory of Open Access Journals (Sweden)

    Janosch Peter Heller

    2015-11-01

    Full Text Available Diseases such as age-related macular degeneration (AMD affect the retinal pigment epithelium (RPE and lead to the death of the epithelial cells and ultimately blindness. RPE transplantation is currently a major focus of eye research and clinical trials using human stem cell-derived RPE cells are ongoing. However, it remains to be established to which extent the source of RPE cells for transplantation affects their therapeutic efficacy and this needs to be explored in animal models. Autotransplantation of RPE cells has attractions as a therapy, but existing protocols to isolate adult RPE cells from rodents are technically difficult, time-consuming, have a low yield and are not optimized for long-term cell culturing. Here, we report a newly devised protocol which facilitates reliable and simple isolation and culture of RPE cells from adult rats. Incubation of a whole rat eyeball in 20 U/ml papain solution for 50 minutes yielded 4 x 104 viable RPE cells. These cells were hexagonal and pigmented upon culture. Using immunostaining, we demonstrated that the cells expressed RPE cell-specific marker proteins including cytokeratin 18 and RPE65, similar to RPE cells in vivo. Additionally, the cells were able to produce and secrete Bruch’s membrane matrix components similar to in vivo situation. Similarly, the cultured RPE cells adhered to isolated Bruch’s membrane as has previously been reported. Therefore, the protocol described in this article provides an efficient method for the rapid and easy isolation of high quantities of adult rat RPE cells. This provides a reliable platform for studying the therapeutic targets, testing the effects of drugs in a preclinical setup and to perform in vitro and in vivo transplantation experiments to study retinal diseases.

  7. Specific interaction of Gαi3 with the Oa1 G-protein coupled receptor controls the size and density of melanosomes in retinal pigment epithelium.

    Directory of Open Access Journals (Sweden)

    Alejandra Young

    Full Text Available BACKGROUND: Ocular albinism type 1, an X-linked disease characterized by the presence of enlarged melanosomes in the retinal pigment epithelium (RPE and abnormal crossing of axons at the optic chiasm, is caused by mutations in the OA1 gene. The protein product of this gene is a G-protein-coupled receptor (GPCR localized in RPE melanosomes. The Oa1-/- mouse model of ocular albinism reproduces the human disease. Oa1 has been shown to immunoprecipitate with the Gαi subunit of heterotrimeric G proteins from human skin melanocytes. However, the Gαi subfamily has three highly homologous members, Gαi1, Gαi2 and Gαi3 and it is possible that one or more of them partners with Oa1. We had previously shown by in-vivo studies that Gαi3-/- and Oa1-/- mice have similar RPE phenotype and decussation patterns. In this paper we analyze the specificity of the Oa1-Gαi interaction. METHODOLOGY: By using the genetic mouse models Gαi1-/-, Gαi2-/-, Gαi3-/- and the double knockout Gαi1-/-, Gαi3-/- that lack functional Gαi1, Gαi2, Gαi3, or both Gαi1 and Gαi3 proteins, respectively, we show that Gαi3 is critical for the maintenance of a normal melanosomal phenotype and that its absence is associated with changes in melanosomal size and density. GST-pull-down and immunoprecipitation assays conclusively demonstrate that Gαi3 is the only Gαi that binds to Oa1. Western blots show that Gαi3 expression is barely detectable in the Oa1-/- RPE, strongly supporting a previously unsuspected role for Gαi3 in melanosomal biogenesis. CONCLUSION: Our results identify the Oa1 transducer Gαi3 as the first downstream component in the Oa1 signaling pathway.

  8. Actin capping protein alpha maintains vestigial-expressing cells within the Drosophila wing disc epithelium.

    Science.gov (United States)

    Janody, Florence; Treisman, Jessica E

    2006-09-01

    Tissue patterning must be translated into morphogenesis through cell shape changes mediated by remodeling of the actin cytoskeleton. We have found that Capping protein alpha (Cpa) and Capping protein beta (Cpb), which prevent extension of the barbed ends of actin filaments, are specifically required in the wing blade primordium of the Drosophila wing disc. cpa or cpb mutant cells in this region, but not in the remainder of the wing disc, are extruded from the epithelium and undergo apoptosis. Excessive actin filament polymerization is not sufficient to explain this phenotype, as loss of Cofilin or Cyclase-associated protein does not cause cell extrusion or death. Misexpression of Vestigial, the transcription factor that specifies the wing blade, both increases cpa transcription and makes cells dependent on cpa for their maintenance in the epithelium. Our results suggest that Vestigial specifies the cytoskeletal changes that lead to morphogenesis of the adult wing.

  9. Pigments and ultrastructures of pigment cells in xanthic sailfin mollies (Poecilia latipinna).

    Science.gov (United States)

    Blanchard, P D; Angus, R A; Morrison, R L; Frost-Mason, S K; Sheetz, J H

    1991-12-01

    Electron micrographs of skin from xanthic (gold) sailfin mollies revealed numerous xanthophores, as well as scattered melanophores. The melanophores were seen to contain premelanosomes in various stages of development. This is consistent with the fact that xanthic mollies have been shown to be tyrosinase positive. Melanosomes in xanthic mollies appear to develop by one of two pathways: 1) from an endoplasmic reticulum-derived vesicle which develops an internal lamellar framework, and 2) by fusion of multiple Golgi-derived vesicles which lack an internal lamellar framework. Analysis of the pigments in the skin of the xanthic mollies identified four colorless pteridine pigments (xanthopterin, isoxanthopterin, neopterin, and pterin) and a carotenoid with an absorbance spectrum similar to beta-carotene. It appears that, unlike some other poeciliid fishes, sailfin mollies do not use pteridine pigments for orange coloration. Rather, they appear to rely primarily on carotenoids.

  10. Generation of human female reproductive tract epithelium from human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Louie Ye

    Full Text Available BACKGROUND: Recent studies have identified stem/progenitor cells in human and mouse uterine epithelium, which are postulated to be responsible for tissue regeneration and proliferative disorders of human endometrium. These progenitor cells are thought to be derived from Müllerian duct (MD, the primordial female reproductive tract (FRT. METHODOLOGY/PRINCIPAL FINDINGS: We have developed a model of human reproductive tract development in which inductive neonatal mouse uterine mesenchyme (nMUM is recombined with green fluorescent protein (GFP-tagged human embryonic stem cells (hESCs; GFP-hESC (ENVY. We demonstrate for the first time that hESCs can be differentiated into cells with a human FRT epithelial cell phenotype. hESC derived FRT epithelial cells emerged from cultures containing MIXL1(+ mesendodermal precursors, paralleling events occurring during normal organogenesis. Following transplantation, nMUM treated embryoid bodies (EBs generated epithelial structures with a typical MD phenotype that expressed the MD markers PAX2, HOXA10. Functionally, the hESCs derived FRT epithelium responded to exogenous estrogen by proliferating and secreting uterine-specific glycodelin A (GdA. CONCLUSIONS/SIGNIFICANCE: These data show nMUM can induce differentiation of hESC to form the FRT epithelium. This may provide a model to study early developmental events of the human FRT.

  11. Identification of transcription factors that promote the differentiation of human pluripotent stem cells into lacrimal gland epithelium-like cells.

    Science.gov (United States)

    Hirayama, Masatoshi; Ko, Shigeru B H; Kawakita, Tetsuya; Akiyama, Tomohiko; Goparaju, Sravan K; Soma, Atsumi; Nakatake, Yuhki; Sakota, Miki; Chikazawa-Nohtomi, Nana; Shimmura, Shigeto; Tsubota, Kazuo; Ko, Minoru S H

    2017-01-01

    Dry eye disease is the most prevalent pathological condition in aging eyes. One potential therapeutic strategy is the transplantation of lacrimal glands, generated in vitro from pluripotent stem cells such as human embryonic stem cells, into patients. One of the preceding requirements is a method to differentiate human embryonic stem cells into lacrimal gland epithelium cells. As the first step for this approach, this study aims to identify a set of transcription factors whose overexpression can promote the differentiation of human embryonic stem cells into lacrimal gland epithelium-like cells. We performed microarray analyses of lacrimal glands and lacrimal glands-related organs obtained from mouse embryos and adults, and identified transcription factors enriched in lacrimal gland epithelium cells. We then transfected synthetic messenger RNAs encoding human orthologues of these transcription factors into human embryonic stem cells and examined whether the human embryonic stem cells differentiate into lacrimal gland epithelium-like cells by assessing cell morphology and marker gene expression. The microarray analysis of lacrimal glands tissues identified 16 transcription factors that were enriched in lacrimal gland epithelium cells. We focused on three of the transcription factors, because they are expressed in other glands such as salivary glands and are also known to be involved in the development of lacrimal glands. We tested the overexpression of various combinations of the three transcription factors and PAX6, which is an indispensable gene for lacrimal glands development, in human embryonic stem cells. Combining PAX6, SIX1, and FOXC1 caused significant changes in morphology, i.e., elongated cell shape and increased expression (both RNAs and proteins) of epithelial markers such as cytokeratin15, branching morphogenesis markers such as BARX2, and lacrimal glands markers such as aquaporin5 and lactoferrin. We identified a set of transcription factors enriched in

  12. Lipoxin A4 inhibits immune cell binding to salivary epithelium and vascular endothelium.

    Science.gov (United States)

    Chinthamani, Sreedevi; Odusanwo, Olutayo; Mondal, Nandini; Nelson, Joel; Neelamegham, Sriram; Baker, Olga J

    2012-04-01

    Lipoxins are formed by leukocytes during cell-cell interactions with epithelial or endothelial cells. Native lipoxin A(4) (LXA(4)) binds to the G protein-coupled lipoxin receptors formyl peptide receptor 2 (FPR2)/ALX and CysLT1. Furthermore, LXA(4) inhibits recruitment of neutrophils, by attenuating chemotaxis, adhesion, and transmigration across vascular endothelial cells. LXA(4) thus appears to serve as an endogenous "stop signal" for immune cell-mediated tissue injury (Serhan CN; Annu Rev Immunol 25: 101-137, 2007). The role of LXA(4) has not been addressed in salivary epithelium, and little is known about its effects on vascular endothelium. Here, we determined that interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) receptor activation in vascular endothelium and salivary epithelium upregulated the expression of adhesion molecules that facilitates the binding of immune cells. We hypothesize that the activation of the ALX/FPR2 and/or CysLT1 receptors by LXA(4) decreases this cytokine-mediated upregulation of cell adhesion molecules that enhance lymphocyte binding to both the vascular endothelium and salivary epithelium. In agreement with this hypothesis, we observed that nanomolar concentrations of LXA(4) blocked IL-1β- and TNF-α-mediated upregulation of E-selectin and intercellular cell adhesion molecule-1 (ICAM-1) on human umbilical vein endothelial cells (HUVECs). Binding of Jurkat cells to stimulated HUVECs was abrogated by LXA(4). Furthermore, LXA(4) preincubation with human submandibular gland cell line (HSG) also blocked TNF-α-mediated upregulation of vascular cell adhesion molecule-1 (VCAM-1) in these cells, and it reduced lymphocyte adhesion. These findings suggest that ALX/FPR2 and/or CysLT1 receptor activation in endothelial and epithelial cells blocks cytokine-induced adhesion molecule expression and consequent binding of lymphocytes, a critical event in the pathogenesis of Sjögren's syndrome (SS).

  13. Pigments from UV-resistant Antarctic bacteria as photosensitizers in Dye Sensitized Solar Cells.

    Science.gov (United States)

    Órdenes-Aenishanslins, N; Anziani-Ostuni, G; Vargas-Reyes, M; Alarcón, J; Tello, A; Pérez-Donoso, J M

    2016-09-01

    Here we report the use of pigments produced by UV-resistant Antarctic bacteria as photosensitizers in Dye Sensitized Solar Cells (DSSCs). Pigments were obtained from red and yellow colored psychrotolerant bacteria isolated from soils of King George Island, Antarctica. Based on metabolic characteristics and 16s DNA sequence, pigmented bacteria were identified as Hymenobacter sp. (red) and Chryseobacterium sp. (yellow). Pigments produced by these microorganisms were extracted and classified as carotenoids based on their spectroscopic and structural characteristics, determined by UV-Vis spectrophotometry and infrared spectroscopy (FTIR), respectively. With the purpose of develop green solar cells based on bacterial pigments, the photostability and capacity of these molecules as light harvesters in DSSCs were determined. Absorbance decay assays determined that bacterial carotenoids present high photostability. In addition, solar cells based on these photosensitizers exhibit an open circuit voltage (VOC) of 435.0 [mV] and a short circuit current density (ISC) of 0.2 [mA·cm(-2)] for the red pigment, and a VOC of 548.8 [mV] and a ISC of 0.13 [mA·cm(-2)] for the yellow pigment. This work constitutes the first approximation of the use of pigments produced by non-photosynthetic bacteria as photosensitizers in DSSCs. Determined photochemical characteristics of bacterial pigments, summed to their easy obtention and low costs, validates its application as photosensitizers in next-generation biological solar cells.

  14. Midgut epithelium in molting silkworm: A fine balance among cell growth, differentiation, and survival.

    Science.gov (United States)

    Franzetti, Eleonora; Casartelli, Morena; D'Antona, Paola; Montali, Aurora; Romanelli, Davide; Cappellozza, Silvia; Caccia, Silvia; Grimaldi, Annalisa; de Eguileor, Magda; Tettamanti, Gianluca

    2016-07-01

    The midgut of insects has attracted great attention as a system for studying intestinal stem cells (ISCs) as well as cell death-related processes, such as apoptosis and autophagy. Among insects, Lepidoptera represent a good model to analyze these cells and processes. In particular, larva-larva molting is an interesting developmental phase since the larva must deal with nutrient starvation and its organs are subjected to rearrangements due to proliferation and differentiation events. Several studies have analyzed ISCs in vitro and characterized key factors involved in their division and differentiation during molt. However, in vivo studies performed during larva-larva transition on these cells, and on the whole midgut epithelium, are fragmentary. In the present study, we analyzed the larval midgut epithelium of the silkworm, Bombyx mori, during larva-larva molting, focusing our attention on ISCs. Moreover, we investigated the metabolic changes that occur in the epithelium and evaluated the intervention of autophagy. Our data on ISCs proliferation and differentiation, autophagy activation, and metabolic and functional activities of the midgut cells shed light on the complexity of this organ during the molting phase.

  15. Selective impairment of a subset of Ran-GTP-binding domains of ran-binding protein 2 (Ranbp2) suffices to recapitulate the degeneration of the retinal pigment epithelium (RPE) triggered by Ranbp2 ablation.

    Science.gov (United States)

    Patil, Hemangi; Saha, Arjun; Senda, Eugene; Cho, Kyoung-in; Haque, MdEmdadul; Yu, Minzhong; Qiu, Sunny; Yoon, Dosuk; Hao, Ying; Peachey, Neal S; Ferreira, Paulo A

    2014-10-24

    Retinal pigment epithelium (RPE) degeneration underpins diseases triggered by disparate genetic lesions, noxious insults, or both. The pleiotropic Ranbp2 controls the expression of intrinsic and extrinsic pathological stressors impinging on cellular viability. However, the physiological targets and mechanisms controlled by Ranbp2 in tissue homeostasis, such as RPE, are ill defined. We show that mice, RPE-cre::Ranbp2(-/-), with selective Ranbp2 ablation in RPE develop pigmentary changes, syncytia, hypoplasia, age-dependent centrifugal and non-apoptotic degeneration of the RPE, and secondary leakage of choriocapillaris. These manifestations are accompanied by the development of F-actin clouds, metalloproteinase-11 activation, deregulation of expression or subcellular localization of critical RPE proteins, atrophic cell extrusions into the subretinal space, and compensatory proliferation of peripheral RPE. To gain mechanistic insights into what Ranbp2 activities are vital to the RPE, we performed genetic complementation analyses of transgenic lines of bacterial artificial chromosomes of Ranbp2 harboring loss of function of selective Ranbp2 domains expressed in a Ranbp2(-/-) background. Among the transgenic lines produced, only Tg(RBD2/3*-HA)::RPE-cre::Ranbp2(-/-)-expressing mutations, which selectively impair binding of RBD2/3 (Ran-binding domains 2 and 3) of Ranbp2 to Ran-GTP, recapitulate RPE degeneration, as observed with RPE-cre::Ranbp2(-/-). By contrast, Tg(RBD2/3*-HA) expression rescues the degeneration of cone photoreceptors lacking Ranbp2. The RPE of RPE-cre::Ranbp2(-/-) and Tg(RBD2/3*-HA)::RPE-cre::Ranbp2(-/-) share proteostatic deregulation of Ran GTPase, serotransferrin, and γ-tubulin and suppression of light-evoked electrophysiological responses. These studies unravel selective roles of Ranbp2 and its RBD2 and RBD3 in RPE survival and functions. We posit that the control of Ran GTPase by Ranbp2 emerges as a novel therapeutic target in diseases promoting

  16. Primary cell cultures of bovine colon epithelium: isolation and cell culture of colonocytes.

    Science.gov (United States)

    Föllmann, W; Weber, S; Birkner, S

    2000-10-01

    Epithelial cells from bovine colon were isolated by mechanical preparation combined with an enzymatic digestion from colon specimens derived from freshly slaughtered animals. After digestion with collagenase I, the isolated tissue was centrifuged on a 2% D-sorbitol gradient to separate epithelial crypts which were seeded in collagen I-coated culture flasks. By using colon crypts and omitting the seeding of single cells a contamination by fibroblasts was prevented. The cells proliferated under the chosen culture conditions and formed monolayer cultures which were maintained for several weeks, including subcultivation steps. A population doubling time of about 21 hr was estimated in the log phase of the corresponding growth curve. During the culture period the cells were characterized morphologically and enzymatically. By using antibodies against cytokeratine 7 and 13 the isolated cells were identified as cells of epithelial origin. Antibodies against vimentin served as negative control. Morphological features such as microvilli, desmosomes and tight junctions, which demonstrated the ability of the cultured cells to restore an epithelial like monolayer, were shown by ultrastructural investigations. The preservation of the secretory function of the cultured cells was demonstrated by mucine cytochemistry with alcian blue staining. A stable expression of enzyme activities over a period of 6 days in culture occurred for gamma-glutamyltranspeptidase, acid phosphatase and NADH-dehydrogenase activity under the chosen culture conditions. Activity of alkaline phosphatase decreased to about 50% of basal value after 6 days in culture. Preliminary estimations of the metabolic competence of these cells revealed cytochrome P450 1A1-associated EROD activity in freshly isolated cells which was stable over 5 days in cultured cells. Then activity decreased completely. This culture system with primary epithelial cells from the colon will be used further as a model for the colon

  17. Skin Pigmentation Disorders

    Science.gov (United States)

    Pigmentation means coloring. Skin pigmentation disorders affect the color of your skin. Your skin gets its color from a pigment called melanin. Special cells in the skin make melanin. When these cells become damaged or ...

  18. Lung endothelial cells strengthen, but brain endothelial cells weaken barrier properties of a human alveolar epithelium cell culture model.

    Science.gov (United States)

    Neuhaus, Winfried; Samwer, Fabian; Kunzmann, Steffen; Muellenbach, Ralf M; Wirth, Michael; Speer, Christian P; Roewer, Norbert; Förster, Carola Y

    2012-11-01

    The blood-air barrier in the lung consists of the alveolar epithelium, the underlying capillary endothelium, their basement membranes and the interstitial space between the cell layers. Little is known about the interactions between the alveolar and the blood compartment. The aim of the present study was to gain first insights into the possible interplay between these two neighbored cell layers. We established an in vitro Transwell model of the alveolar epithelium based on human cell line H441 and investigated the influence of conditioned medium obtained from human lung endothelial cell line HPMEC-ST1.6R on the barrier properties of the H441 layers. As control for tissue specificity H441 layers were exposed to conditioned medium from human brain endothelial cell line hCMEC/D3. Addition of dexamethasone was necessary to obtain stable H441 cell layers. Moreover, dexamethasone increased expression of cell type I markers (caveolin-1, RAGE) and cell type II marker SP-B, whereas decreased the transepithelial electrical resistance (TEER) in a concentration dependent manner. Soluble factors obtained from the lung endothelial cell line increased the barrier significantly proven by TEER values and fluorescein permeability on the functional level and by the differential expression of tight junctional proteins on the molecular level. In contrast to this, soluble factors derived from brain endothelial cells weakened the barrier significantly. In conclusion, soluble factors from lung endothelial cells can strengthen the alveolar epithelium barrier in vitro, which suggests communication between endothelial and epithelial cells regulating the integrity of the blood-air barrier.

  19. Damage to lens fiber cells causes TRPV4-dependent Src family kinase activation in the epithelium.

    Science.gov (United States)

    Shahidullah, M; Mandal, A; Delamere, N A

    2015-11-01

    The bulk of the lens consists of tightly packed fiber cells. Because mature lens fibers lack mitochondria and other organelles, lens homeostasis relies on a monolayer of epithelial cells at the anterior surface. The detection of various signaling pathways in lens epithelial cells suggests they respond to stimuli that influence lens function. Focusing on Src Family Kinases (SFKs) and Transient Receptor Potential Vanilloid 4 (TRPV4), we tested whether the epithelium can sense and respond to an event that occurs in fiber mass. The pig lens was subjected to localized freeze-thaw (FT) damage to fibers at posterior pole then the lens was incubated for 1-10 min in Krebs solution at 37 °C. Transient SFK activation in the epithelium was detectable at 1 min. Using a western blot approach, the ion channel TRPV4 was detected in the epithelium but was sparse or absent in fiber cells. Even though TRPV4 expression appears low at the actual site of FT damage to the fibers, SFK activation in the epithelium was suppressed in lenses subjected to FT damage then incubated with the TRPV4 antagonist HC067047 (10 μM). Na,K-ATPase activity was examined because previous studies report changes of Na,K-ATPase activity associated with SFK activation. Na,K-ATPase activity doubled in the epithelium removed from FT-damaged lenses and the response was prevented by HC067047 or the SFK inhibitor PP2 (10 μM). Similar changes were observed in response to fiber damage caused by injection of 5 μl hyperosmotic NaCl or mannitol solution beneath the surface of the posterior pole. The findings point to a TRPV4-dependent mechanism that enables the epithelial cells to detect remote damage in the fiber mass and respond within minutes by activating SFK and increasing Na,K-ATPase activity. Because TRPV4 channels are mechanosensitive, we speculate they may be stimulated by swelling of the lens structure caused by damage to the fibers. Increased Na,K-ATPase activity gives the lens greater capacity to

  20. Protective Effects of Human iPS-Derived Retinal Pigmented Epithelial Cells in Comparison with Human Mesenchymal Stromal Cells and Human Neural Stem Cells on the Degenerating Retina in rd1 mice.

    Science.gov (United States)

    Sun, Jianan; Mandai, Michiko; Kamao, Hiroyuki; Hashiguchi, Tomoyo; Shikamura, Masayuki; Kawamata, Shin; Sugita, Sunao; Takahashi, Masayo

    2015-05-01

    Retinitis pigmentosa (RP) is a group of visual impairments characterized by progressive rod photoreceptor cell loss due to a genetic background. Pigment epithelium-derived factor (PEDF) predominantly secreted by the retinal pigmented epithelium (RPE) has been reported to protect photoreceptors in retinal degeneration models, including rd1. In addition, clinical trials are currently underway outside Japan using human mesenchymal stromal cells and human neural stem cells to protect photoreceptors in RP and dry age-related macular degeneration, respectively. Thus, this study aimed to investigate the rescue effects of induced pluripotent stem (iPS)-RPE cells in comparison with those types of cells used in clinical trials on photoreceptor degeneration in rd1 mice. Cells were injected into the subretinal space of immune-suppressed 2-week-old rd1 mice. The results demonstrated that human iPS-RPE cells significantly attenuated photoreceptor degeneration on postoperative days (PODs) 14 and 21 and survived longer up to at least 12 weeks after operation than the other two types of graft cells with less immune responses and apoptosis. The mean PEDF concentration in the intraocular fluid in RPE-transplanted eyes was more than 1 µg/ml at PODs 14 and 21, and this may have contributed to the protective effect of RPE transplantation. Our findings suggest that iPS-RPE cells serve as a competent source to delay photoreceptor degeneration through stable survival in degenerating ocular environment and by releasing neuroprotective factors such as PEDF.

  1. Eya1 controls cell polarity, spindle orientation, cell fate and Notch signaling in distal embryonic lung epithelium.

    Science.gov (United States)

    El-Hashash, Ahmed H K; Turcatel, Gianluca; Al Alam, Denise; Buckley, Sue; Tokumitsu, Hiroshi; Bellusci, Saverio; Warburton, David

    2011-04-01

    Cell polarity, mitotic spindle orientation and asymmetric division play a crucial role in the self-renewal/differentiation of epithelial cells, yet little is known about these processes and the molecular programs that control them in embryonic lung distal epithelium. Herein, we provide the first evidence that embryonic lung distal epithelium is polarized with characteristic perpendicular cell divisions. Consistent with these findings, spindle orientation-regulatory proteins Insc, LGN (Gpsm2) and NuMA, and the cell fate determinant Numb are asymmetrically localized in embryonic lung distal epithelium. Interfering with the function of these proteins in vitro randomizes spindle orientation and changes cell fate. We further show that Eya1 protein regulates cell polarity, spindle orientation and the localization of Numb, which inhibits Notch signaling. Hence, Eya1 promotes both perpendicular division as well as Numb asymmetric segregation to one daughter in mitotic distal lung epithelium, probably by controlling aPKCζ phosphorylation. Thus, epithelial cell polarity and mitotic spindle orientation are defective after interfering with Eya1 function in vivo or in vitro. In addition, in Eya1(-/-) lungs, perpendicular division is not maintained and Numb is segregated to both daughter cells in mitotic epithelial cells, leading to inactivation of Notch signaling. As Notch signaling promotes progenitor cell identity at the expense of differentiated cell phenotypes, we test whether genetic activation of Notch could rescue the Eya1(-/-) lung phenotype, which is characterized by loss of epithelial progenitors, increased epithelial differentiation but reduced branching. Indeed, genetic activation of Notch partially rescues Eya1(-/-) lung epithelial defects. These findings uncover novel functions for Eya1 as a crucial regulator of the complex behavior of distal embryonic lung epithelium.

  2. GRHL2 coordinates regeneration of a polarized mucociliary epithelium from basal stem cells.

    Science.gov (United States)

    Gao, Xia; Bali, Aman S; Randell, Scott H; Hogan, Brigid L M

    2015-11-09

    Pseudostratified airway epithelium of the lung is composed of polarized ciliated and secretory cells maintained by basal stem/progenitor cells. An important question is how lineage choice and differentiation are coordinated with apical-basal polarity and epithelial morphogenesis. Our previous studies indicated a key integrative role for the transcription factor Grainyhead-like 2 (Grhl2). In this study, we present further evidence for this model using conditional gene deletion during the regeneration of airway epithelium and clonal organoid culture. We also use CRISPR/Cas9 genome editing in primary human basal cells differentiating into organoids and mucociliary epithelium in vitro. Loss of Grhl2 inhibits organoid morphogenesis and the differentiation of ciliated cells and reduces the expression of both notch and ciliogenesis genes (Mcidas, Rfx2, and Myb) with distinct Grhl2 regulatory sites. The genome editing of other putative target genes reveals roles for zinc finger transcription factor Znf750 and small membrane adhesion glycoprotein in promoting ciliogenesis and barrier function as part of a network of genes coordinately regulated by Grhl2.

  3. TR146 cells grown on filters as a model of human buccal epithelium

    DEFF Research Database (Denmark)

    Nielsen, Hanne Mørck; Verhoef, J C; Ponec, M

    1999-01-01

    The aim of the present study was to characterize the TR146 cell culture model as an in vitro model of human buccal epithelium with respect to the permeability of test substances with different molecular weights (M(w)). For this purpose, the apparent permeability (P(app)) values for mannitol...... and for fluorescein isothiocyanate (FITC)-labelled dextrans (FD) with various M(w) (4000-40000) were compared to the P(app) values obtained using porcine buccal mucosa as an in vitro model of the human buccal epithelium. The effect of 10 mM sodium glycocholate (GC) on the P(app) values was examined. To identify...... cell culture model is a suitable in vitro model for mechanistic permeability studies of human buccal drug permeability....

  4. [Human amniotic epithelium (HAE) as a possible source of stem cells (SC)].

    Science.gov (United States)

    García-López, Guadalupe; García-Castro, Irma Lydia; Avila-González, Daniela; Molina-Hernández, Anayansi; Flores-Herrera, Héctor; Merchant-Larios, Horacio; Díaz-Martínez, Fabián

    2015-01-01

    There have been major recent advances in the field of developmental biology due to the investigation on stem cells (SC). Stem cells are characterized by their capacity of auto-renewal and differentiation to different cellular phenotypes. Based on the developmental stage, they can be classified into two different types: embryonic SCs and adult SCs. It has been widely reported that several problems need to be resolved before their possible clinical applications. As a result, fetal membranes have been suggested as an alternative source of SCs. In the human amniotic epithelium, the presence of markers of pluripotent SC´s has been reported, and its capacity as a feeder layer for expansion of different SC types. Also, fetal membranes are a discarded product after delivery, and thus there are not any ethical issues related to its use. In conclusion, the human amniotic epithelium can be a strong candidate for regenerative medicine.

  5. Bacterial endotoxin activates retinal pigment epithelial cells and induces their degeneration through IL-6 and IL-8 autocrine signaling.

    Science.gov (United States)

    Leung, Kar Wah; Barnstable, Colin J; Tombran-Tink, Joyce

    2009-04-01

    Inflammation is a major contributing factor to many blinding disorders including uveitis, diabetic retinopathy, and age-related macular degeneration. Here we examined the response of the retinal pigment epithelium (RPE) to physiological levels of lipopolysaccharide (LPS) to understand the role of this epithelium in inflammatory retinal conditions. Expression of a group of inflammatory mediators was identified by gene array analysis and confirmed by PCR and immunocytochemistry in primary human RPE cultures and ARPE19. The effects of LPS on the expression of these cytokines and RPE survival were examined by PCR, Luminex bead, and MTT assays. RPE cells express many cytokine receptors including IL-1R, -4R, -6R, -8RA, IFNAR1, IFNGR1/2 and secrete a range of pro- and anti-inflammatory cytokines including IL-4, -6, -8, -10, -17, IFN-gamma, MCP-1, and VEGF. LPS increases IL-13RA1 and IFNAR1, and decreases IL-7R receptor expression. It also increases RPE secretion of IL-4, -6, -8, -10, IFN-gamma and MCP-1, and is toxic to RPE cells at LC(50)=17.7 microg/ml. LPS toxicity is mediated by IL-6 and IL-8 through an autocrine feedback loop. Silencing IL-6R and IL-8RA gene expression by siRNA blocks death by their respective ligands or LPS. These findings imply that RPE cells are acutely sensitive to inflammatory stress and that over secretion of IL-6 and IL-8 by this epithelium during inflammatory stimulus may be an underlying factor in the progression of some retinal pathologies.

  6. TR146 cells grown on filters as a model of human buccal epithelium

    DEFF Research Database (Denmark)

    Nielsen, Hanne Mørck; Rassing, M R

    1999-01-01

    The aim of the present study was to evaluate the TR146 cell culture model as an in vitro model of human buccal epithelium with respect to the permeability enhancement by different pH values, different osmolality values or bile salts. For this purpose, the increase in the apparent permeability (P...... for efficacy studies and mechanistic studies of enhancers with potential use in human buccal drug delivery....

  7. The Bacillus thuringiensis vegetative insecticidal protein Vip3A lyses midgut epithelium cells of susceptible insects.

    OpenAIRE

    Yu, C G; Mullins, M A; Warren, G W; Koziel, M G; Estruch, J J

    1997-01-01

    The Vip3A protein is a member of a newly discovered class of vegetative insecticidal proteins with activity against a broad spectrum of lepidopteran insects. Histopathological observations indicate that Vip3A ingestion by susceptible insects such as the black cutworm (Agrotis ipsilon) and fall armyworm (Spodoptera frugiperda) causes gut paralysis at concentrations as low as 4 ng/cm2 of diet and complete lysis of gut epithelium cells resulting in larval death at concentrations above 40 ng/cm2....

  8. Cytotoxic effects of curcumin in human retinal pigment epithelial cells.

    Directory of Open Access Journals (Sweden)

    Margrit Hollborn

    Full Text Available BACKGROUND: Curcumin from turmeric is an ingredient in curry powders. Due to its antiinflammatory, antioxidant and anticarcinogenic effects, curcumin is a promising drug for the treatment of cancer and retinal diseases. We investigated whether curcumin alters the viability and physiological properties of human retinal pigment epithelial (RPE cells in vitro. METHODOLOGY/PRINCIPAL FINDINGS: Cellular proliferation was investigated with a bromodeoxy-uridine immunoassay, and chemotaxis was investigated with a Boyden chamber assay. Cell viability was determined by trypan blue exclusion. Apoptosis and necrosis rates were determined with a DNA fragmentation ELISA. Gene expression was determined by real-time PCR, and secretion of VEGF and bFGF was examined with ELISA. The phosphorylation level of proteins was revealed by Western blotting. The proliferation of RPE cells was slightly increased by curcumin at 10 µM and strongly reduced by curcumin above 50 µM. Curcumin at 50 µM increased slightly the chemotaxis of the cells. Curcumin reduced the expression and secretion of VEGF under control conditions and abolished the VEGF secretion induced by PDGF and chemical hypoxia. Whereas low concentrations of curcumin stimulated the expression of bFGF and HGF, high concentrations caused downregulation of both factors. Curcumin decreased dose-dependently the viability of RPE cells via induction of early necrosis (above 10 µM and delayed apoptosis (above 1 µM. The cytotoxic effect of curcumin involved activation of caspase-3 and calpain, intracellular calcium signaling, mitochondrial permeability, oxidative stress, increased phosphorylation of p38 MAPK and decreased phosphorylation of Akt protein. CONCLUSION: It is concluded that curcumin at concentrations described to be effective in the treatment of tumor cells and in inhibiting death of retinal neurons (∼10 µM has adverse effects on RPE cells. It is suggested that, during the intake of curcumin as

  9. Cytotoxic Effects of Curcumin in Human Retinal Pigment Epithelial Cells

    Science.gov (United States)

    Hollborn, Margrit; Chen, Rui; Wiedemann, Peter; Reichenbach, Andreas; Bringmann, Andreas; Kohen, Leon

    2013-01-01

    Backround Curcumin from turmeric is an ingredient in curry powders. Due to its antiinflammatory, antioxidant and anticarcinogenic effects, curcumin is a promising drug for the treatment of cancer and retinal diseases. We investigated whether curcumin alters the viability and physiological properties of human retinal pigment epithelial (RPE) cells in vitro. Methodology/Principal Findings Cellular proliferation was investigated with a bromodeoxy-uridine immunoassay, and chemotaxis was investigated with a Boyden chamber assay. Cell viability was determined by trypan blue exclusion. Apoptosis and necrosis rates were determined with a DNA fragmentation ELISA. Gene expression was determined by real-time PCR, and secretion of VEGF and bFGF was examined with ELISA. The phosphorylation level of proteins was revealed by Western blotting. The proliferation of RPE cells was slightly increased by curcumin at 10 µM and strongly reduced by curcumin above 50 µM. Curcumin at 50 µM increased slightly the chemotaxis of the cells. Curcumin reduced the expression and secretion of VEGF under control conditions and abolished the VEGF secretion induced by PDGF and chemical hypoxia. Whereas low concentrations of curcumin stimulated the expression of bFGF and HGF, high concentrations caused downregulation of both factors. Curcumin decreased dose-dependently the viability of RPE cells via induction of early necrosis (above 10 µM) and delayed apoptosis (above 1 µM). The cytotoxic effect of curcumin involved activation of caspase-3 and calpain, intracellular calcium signaling, mitochondrial permeability, oxidative stress, increased phosphorylation of p38 MAPK and decreased phosphorylation of Akt protein. Conclusion It is concluded that curcumin at concentrations described to be effective in the treatment of tumor cells and in inhibiting death of retinal neurons (∼10 µM) has adverse effects on RPE cells. It is suggested that, during the intake of curcumin as concomitant therapy of

  10. Near Equilibrium Calculus of Stem Cells in Application to the Airway Epithelium Lineage

    Science.gov (United States)

    Sun, Zheng; Plikus, Maksim V.; Komarova, Natalia L.

    2016-01-01

    Homeostatic maintenance of tissues is orchestrated by well tuned networks of cellular signaling. Such networks regulate, in a stochastic manner, fates of all cells within the respective lineages. Processes such as symmetric and asymmetric divisions, differentiation, de-differentiation, and death have to be controlled in a dynamic fashion, such that the cell population is maintained at a stable equilibrium, has a sufficiently low level of stochastic variation, and is capable of responding efficiently to external damage. Cellular lineages in real tissues may consist of a number of different cell types, connected by hierarchical relationships, albeit not necessarily linear, and engaged in a number of different processes. Here we develop a general mathematical methodology for near equilibrium studies of arbitrarily complex hierarchical cell populations, under regulation by a control network. This methodology allows us to (1) determine stability properties of the network, (2) calculate the stochastic variance, and (3) predict how different control mechanisms affect stability and robustness of the system. We demonstrate the versatility of this tool by using the example of the airway epithelium lineage. Recent research shows that airway epithelium stem cells divide mostly asymmetrically, while the so-called secretory cells divide predominantly symmetrically. It further provides quantitative data on the recovery dynamics of the airway epithelium, which can include secretory cell de-differentiation. Using our new methodology, we demonstrate that while a number of regulatory networks can be compatible with the observed recovery behavior, the observed division patterns of cells are the most optimal from the viewpoint of homeostatic lineage stability and minimizing the variation of the cell population size. This not only explains the observed yet poorly understood features of airway tissue architecture, but also helps to deduce the information on the still largely hypothetical

  11. The injury of serotonin on intestinal epithelium cell renewal of weaned diarrhoea mice

    Directory of Open Access Journals (Sweden)

    Y. Dong

    2016-12-01

    Full Text Available Diarrhoea is a common cause of death in children and weaned animals. Recent research has found that serotonin (5-HT in the gastrointestinal tract plays an important role in regulating growth and the maintenance of mucosa, which protect against diarrhoea. To determine the influence of 5-HT on intestinal epithelium cell renewal under weaned stress diarrhoea, a weaned-stress diarrhoea mouse model was established with senna infusion (15 mL/Kg via intragastric administration and stress restraint (SR. Mice with an increase in 5-HT were induced by intraperitoneal injection with citalopram hydrobromide (CH, 10 mg/Kg. The results demonstrated that compared with the control animals, diarrhoea appeared in weaned stress mice and the 5-HT content in the small intestine was significantly increased (P<0.05. Further, the caspase-3 cells and cells undergoing apoptosis in the small intestine were significantly increased, but the VH (villus height, V/C (villus height /crypt depth, and PCNA-positive rate significantly decreased. Compared with the control animals, CH increased the intestinal 5-HT content, caspase-3 cells and cells undergoing apoptosis but decreased the VH and V/C. Compared with both control and weaned stress animals, weaned stress animals that were pre-treated with CH showed higher 5-HT concentrations, positive caspase-3 cells and cells undergoing apoptosis but lower VH, V/C and PCNA-positive rate. In vitro, a low concentration of 5-HT inhibit, IEC-6 cell line apoptosis but a higher concentration of 5-HT promoted it. Therefore, weaned stress diarrhoea mice were accompanied by a 5-HT increase in the small intestine and vice versa, and the increase in 5-HT induced by CH caused diarrhoea. In brief, 5-HT and diarrhoea slowed the intestinal epithelium cell renewal and injured the abortion function and mucosal barrier by decreasing VH, V/C and proliferation and increasing epithelium cell apoptosis.

  12. In vitro culture and phagocytosis of human embryonic retinal pigment epithelium%人胚胎视网膜色素上皮细胞的体外培养和吞噬作用

    Institute of Scientific and Technical Information of China (English)

    靳晓亮; 徐国彤; 张文芳; 鲁建华

    2011-01-01

    Objective To analyze the culturing characteristics and phagocytosis of the retinal pigment epithelium (RPE) from human embryo, and to provide the cellular basis for the further research of RPE related diseases. Methods Fresh human embryonic eyeballs (13~15 weeks) were collected, and RPE cells were separated by mechanical and trypsin digestion after microdissec-tion. Human embryonic RPE phagocytosis of retinal outer segments was investigated by using immunofluorescence. Results After the human embryo had developed for 13~15 weeks, the RPE cells could be cultured in vitro according to standard culturing methods. Based on the growth curve, the RPE cells in generations 2~6 were collected for essays and showed the ability of phagocytosis afterwards. Conclusion The method of culturing human embryonic RPE cells is improved, and phagocytosis ability of human embryonic RPE cells is also proved in vitro according to this study.%目的 探讨人胚胎视网膜色素上皮(RPE)细胞分离培养的特性及其吞噬作用.方法 取发育至13~15周的新鲜人胚胎眼球,显微解剖后采用机械胰酶消化法分离培养RPE细胞,应用免疫荧光法观察人胚胎RPE细胞吞噬视网膜光感受细胞外节膜盘.结果 人胚胎发育至13~15周后,RPE细胞可应用标准的培养方法进行体外培养和传代.根据测定的人胚胎RPE细胞生长曲线,取2~6代细胞用于实验培养的人胚胎RPE细胞具备吞噬功能.结论 改进了人胚胎RPE细胞的培养方法,证明人胚胎RPE细胞在体外具有吞噬能力.

  13. Retinal pigment epithelium protein of 65 kDA gene-linked retinal degeneration is not modulated by chicken acidic leucine-rich epidermal growth factor-like domain containing brain protein/Neuroglycan C/ chondroitin sulfate proteoglycan 5.

    Science.gov (United States)

    Cottet, Sandra; Jüttner, René; Voirol, Nathalie; Chambon, Pierre; Rathjen, Fritz G; Schorderet, Daniel F; Escher, Pascal

    2013-01-01

    To analyze in vivo the function of chicken acidic leucine-rich epidermal growth factor-like domain containing brain protein/Neuroglycan C (gene symbol: Cspg5) during retinal degeneration in the Rpe65⁻/⁻ mouse model of Leber congenital amaurosis. We resorted to mice with targeted deletions in the Cspg5 and retinal pigment epithelium protein of 65 kDa (Rpe65) genes (Cspg5⁻/⁻/Rpe65⁻/⁻). Cone degeneration was assessed with cone-specific peanut agglutinin staining. Transcriptional expression of rhodopsin (Rho), S-opsin (Opn1sw), M-opsin (Opn1mw), rod transducin α subunit (Gnat1), and cone transducin α subunit (Gnat2) genes was assessed with quantitative PCR from 2 weeks to 12 months. The retinal pigment epithelium (RPE) was analyzed at P14 with immunodetection of the retinol-binding protein membrane receptor Stra6. No differences in the progression of retinal degeneration were observed between the Rpe65⁻/⁻ and Cspg5⁻/⁻/Rpe65⁻/⁻ mice. No retinal phenotype was detected in the late postnatal and adult Cspg5⁻/⁻ mice, when compared to the wild-type mice. Despite the previously reported upregulation of Cspg5 during retinal degeneration in Rpe65⁻/⁻ mice, no protective effect or any involvement of Cspg5 in disease progression was identified.

  14. Treatment of tenosynovial giant cell tumor and pigmented villonodular synovitis.

    Science.gov (United States)

    Ravi, Vinod; Wang, Wei-Lien; Lewis, Valerae O

    2011-07-01

    To review recent developments in the molecular pathogenesis of tenosynovial giant cell tumor (TGCT) or pigmented villonodular synovitis (PVNS) and its therapeutic implications. TGCT or PVNS is a benign clonal neoplastic proliferation arising from the synovium characterized by a minor population of intratumoral cells that harbor a recurrent translocation. These cells overexpress CSF1, resulting in recruitment of CSF1R-bearing macrophages that are polyclonal and make up the bulk of the tumor. Inhibition of CSF1R using small molecule inhibitors such as imatinib, nilotinib or sunitinib can result in clinical, radiological and functional improvement in the affected joint. Currently, surgery remains the treatment of choice for patients with TGCT/PVNS. Localized TGCT/PVNS is managed by marginal excision. Recurrences occur in 8-20% of patients and are easily managed by re-excision. Diffuse TGCT/PVNS tends to recur more often (33-50%) and has a much more aggressive clinical course. Patients are often symptomatic and require multiple surgical procedures during their lifetime. For patients with unresectable disease or multiple recurrences, systemic therapy using CSF1R inhibitors may help delay or avoid surgical procedures and improve functional outcomes.

  15. Detection of human papillomavirus in Chinese esophageal squamous cell carcinoma and its adjacent normal epithelium

    Institute of Scientific and Technical Information of China (English)

    Xiao-Bo Zhou; Mei Guo; Lan-Ping Quan; Wei Zhang; Zhe-Ming Lu; Quan-Hong Wang; Yang Ke; Ning-Zhi Xu

    2003-01-01

    AIM: To investigate the putative role of human papillomavirus (HPV) infection in the carcinogenesis of esophageal squamous cell carcinoma in China.METHODS: Twenty-three esophageal squamous cell carcinoma samples and the distal normal epithelium from Shanxi Province, and 25 more esophageal squamous cell carcinoma samples from Anyang city, two areas with a high incidence of esophageal cancer in China, were detected for the existence of HPV-16 DNA by PCR, mRNA in situ hybridization (ISH) and immunohistochemistry (IHC) targeting HPV-16 E6 gene. RESULTS: There were approximately 64 % (31/48) patients having HPV-16 DNA in tumor samples, among them nearly twothirds (19/31) samples were detected with mRNA expression of HPV-16 E6. However, in the normal esophageal epithelium from cancer patients, the DNA and mRNA of HPV-16 were found with much less rate: 34.7 % (8/23) and 26.1% (6/23) respectively.In addition, at protein level detected by IHC assay, 27.1% (13/48) tumor samples had virus oncoprotein E6 expression, while only one case of normal epithelium was found positive.CONCLUSION: HPV infection, especially type 16, should be considered as a risk factor for esophageal malignancies in China.

  16. Comparative proteomic analysis of cell lines and scrapings of the human intestinal epithelium

    Directory of Open Access Journals (Sweden)

    Renes Johan

    2007-04-01

    Full Text Available Abstract Background In vitro models are indispensable study objects in the fields of cell and molecular biology, with advantages such as accessibility, homogeneity of the cell population, reproducibility, and growth rate. The Caco-2 cell line, originating from a colon carcinoma, is a widely used in vitro model for small intestinal epithelium. Cancer cells have an altered metabolism, making it difficult to infer their representativity for the tissue from which they are derived. This study was designed to compare the protein expression pattern of Caco-2 cells with the patterns of intestinal epithelial cells from human small and large intestine. HT-29 intestinal cells, Hep G2 liver cells and TE 671 muscle cells were included too, the latter two as negative controls. Results Two-dimensional gel electrophoresis was performed on each tissue and cell line protein sample. Principal component and cluster analysis revealed that global expression of intestinal epithelial scrapings differed from that of intestinal epithelial cell lines. Since all cultured cell lines clustered together, this finding was ascribed to an adaptation of cells to culture conditions and their tumor origin, and responsible proteins were identified by mass spectrometry. When investigating the profiles of Caco-2 cells and small intestinal cells in detail, a considerable overlap was observed. Conclusion Numerous proteins showed a similar expression in Caco-2 cells, HT-29 cells, and both the intestinal scrapings, of which some appear to be characteristic to human intestinal epithelium in vivo. In addition, several biologically significant proteins are expressed at comparable levels in Caco-2 cells and small intestinal scrapings, indicating the usability of this in vitro model. Caco-2 cells, however, appear to over-express as well as under-express certain proteins, which needs to be considered by scientists using this cell line. Hence, care should be taken to prevent misinterpretation of

  17. Remodeling of endogenous mammary epithelium by breast cancer stem cells.

    Science.gov (United States)

    Parashurama, Natesh; Lobo, Neethan A; Ito, Ken; Mosley, Adriane R; Habte, Frezghi G; Zabala, Maider; Smith, Bryan R; Lam, Jessica; Weissman, Irving L; Clarke, Michael F; Gambhir, Sanjiv S

    2012-10-01

    Poorly regulated tissue remodeling results in increased breast cancer risk, yet how breast cancer stem cells (CSC) participate in remodeling is unknown. We performed in vivo imaging of changes in fluorescent, endogenous duct architecture as a metric for remodeling. First, we quantitatively imaged physiologic remodeling of primary branches of the developing and regenerating mammary tree. To assess CSC-specific remodeling events, we isolated CSC from MMTV-Wnt1 (mouse mammary tumor virus long-term repeat enhancer driving Wnt1 oncogene) breast tumors, a well studied model in which tissue remodeling affects tumorigenesis. We confirm that CSC drive tumorigenesis, suggesting a link between CSC and remodeling. We find that normal, regenerating, and developing gland maintain a specific branching pattern. In contrast, transplantation of CSC results in changes in the branching patterns of endogenous ducts while non-CSC do not. Specifically, in the presence of CSC, we identified an increased number of branches, branch points, ducts which have greater than 40 branches (5/33 for CSC and 0/39 for non-CSC), and histological evidence of increased branching. Moreover, we demonstrate that only CSC implants invade into surrounding stroma with structures similar to developing mammary ducts (nine for CSC and one for non-CSC). Overall, we demonstrate a novel approach for imaging physiologic and pathological remodeling. Furthermore, we identify unique, CSC-specific, remodeling events. Our data suggest that CSC interact with the microenvironment differently than non-CSC, and that this could eventually be a therapeutic approach for targeting CSC.

  18. Functional and Molecular Characterization of Rod-like Cells from Retinal Stem Cells Derived from the Adult Ciliary Epithelium

    OpenAIRE

    Gian Carlo Demontis; Claudia Aruta; Antonella Comitato; Anna De Marzo; Valeria Marigo

    2012-01-01

    In vitro generation of photoreceptors from stem cells is of great interest for the development of regenerative medicine approaches for patients affected by retinal degeneration and for high throughput drug screens for these diseases. In this study, we show unprecedented high percentages of rod-fated cells from retinal stem cells of the adult ciliary epithelium. Molecular characterization of rod-like cells demonstrates that they lose ciliary epithelial characteristics but acquire photoreceptor...

  19. Expression of Pigment Cell-Specific Genes in the Ontogenesis of the Sea Urchin Strongylocentrotus intermedius

    Directory of Open Access Journals (Sweden)

    Natalya V. Ageenko

    2011-01-01

    Full Text Available One of the polyketide compounds, the naphthoquinone pigment echinochrome, is synthesized in sea urchin pigment cells. We analyzed polyketide synthase (pks and sulfotransferase (sult gene expression in embryos and larvae of the sea urchin Strongylocentrotus intermedius from various stages of development and in specific tissues of the adults. We observed the highest level of expression of the pks and sult genes at the gastrula stage. In unfertilized eggs, only trace amounts of the pks and sult transcripts were detected, whereas no transcripts of these genes were observed in spermatozoids. The addition of shikimic acid, a precursor of naphthoquinone pigments, to zygotes and embryos increased the expression of the pks and sult genes. Our findings, including the development of specific conditions to promote pigment cell differentiation of embryonic sea urchin cells in culture, represent a definitive study on the molecular signaling pathways that are involved in the biosynthesis of pigments during sea urchin development.

  20. Cell polarity and spindle orientation in the distal epithelium of embryonic lung.

    Science.gov (United States)

    El-Hashash, Ahmed H; Warburton, David

    2011-02-01

    A proper balance between self-renewal and differentiation of lung-specific progenitors at the distal epithelial tips is absolutely required for normal lung morphogenesis. Cell polarity and mitotic spindle orientation play a critical role in the self-renewal/differentiation of epithelial cells and can impact normal physiological processes, including epithelial tissue branching and differentiation. Therefore, understanding the behavior of lung distal epithelial progenitors could identify innovative solutions to restoring normal lung morphogenesis. Yet little is known about cell polarity, spindle orientation, and segregation of cell fate determinant in the embryonic lung epithelium, which contains progenitor cells. Herein, we provide the first evidence that embryonic lung distal epithelium is polarized and highly mitotic with characteristic perpendicular cell divisions. Consistent with these findings, mInsc, LGN, and NuMA polarity proteins, which control spindle orientation, are asymmetrically localized in mitotic distal epithelial progenitors of embryonic lungs. Furthermore, the cell fate determinant Numb is asymmetrically distributed at the apical side of distal epithelial progenitors and segregated to one daughter cell in most mitotic cells. These findings provide evidence for polarity in distal epithelial progenitors of embryonic lungs and provide a framework for future translationally oriented studies in this area.

  1. Biosynthesis of Monascus pigments by resting cell submerged culture in nonionic surfactant micelle aqueous solution.

    Science.gov (United States)

    Wang, Bo; Zhang, Xuehong; Wu, Zhenqiang; Wang, Zhilong

    2016-08-01

    Growing cell submerged culture is usually applied for fermentative production of intracellular orange Monascus pigments, in which accumulation of Monascus pigments is at least partially associated to cell growth. In the present work, extractive fermentation in a nonionic surfactant micelle aqueous solution was utilized as a strategy for releasing of intracellular Monascus pigments. Those mycelia with low content of intracellular Monascus pigments were utilized as biocatalyst in resting cell submerged culture. By this means, resting cell submerged culture for production of orange Monascus pigments was carried out successfully in the nonionic surfactant micelle aqueous solution, which exhibited some advantages comparing with the corresponding conventional growing cell submerged culture, such as non-sterilization operation, high cell density (24 g/l DCW) leading to high productivity (14 AU of orange Monascus pigments at 470 nm per day), and recycling of cells as biocatalyst leading to high product yield (approximately 1 AU of orange Monascus pigments at 470 nm per gram of glucose) based on energy metabolism.

  2. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2012-02-01

    BACKGROUND: Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. RESULTS: Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. CONCLUSION: Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  3. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2011-08-22

    Abstract Background Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. Results Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. Conclusion Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  4. Changes in retinal pigment epithelium related to cigarette smoke: possible relevance to smoking as a risk factor for age-related macular degeneration.

    Directory of Open Access Journals (Sweden)

    Ai Ling Wang

    Full Text Available Age-related Macular Degeneration (AMD is a major cause of central vision loss in the elderly and smoking is a primary risk factor associated with the prevalence and incidence of AMD. To better understand the cellular and molecular bases for the association between smoking and AMD, we determined the effects of Benzo(aPyrene (B(aP, a toxic element in cigarette smoke, on cultured retinal pigment epithelia (RPE and we examined the RPE/choroid from mice exposed to chronic cigarette smoke. We measured: mitochondrial DNA (mtDNA damage, phagocytic activity, lysosomal enzymes, exosome markers and selected complement pathway components. In the presence of a non-cytotoxic dose of B(aP, there was extensive mtDNA damage but no nuclear DNA damage. RPE phagocytic activity was not altered but there were increased lysosomal activity, exocytotic activity and complement pathway components. Retinas from mice exposed to cigarette smoke contained markers for mtDNA damage, exosomes and complement pathway components surrounding Bruch's membrane. Markers for these processes are found in drusen from AMD patients. Thus, smoking may cause damage to mtDNA and increased degradative processes in the RPE. These altered cell biological processes in the RPE may contribute to the formation of drusen in individuals who are cigarette smokers and underlie susceptibility to genetic mutations associated with AMD.

  5. Cyclophilin A is a new M cell marker of bovine intestinal epithelium.

    Science.gov (United States)

    Hondo, Tetsuya; Someya, Shunsuke; Nagasawa, Yuya; Terada, Shunsuke; Watanabe, Hitoshi; Chen, Xiangning; Watanabe, Kouichi; Ohwada, Shyuichi; Kitazawa, Haruki; Rose, Michael T; Nochi, Tomonori; Aso, Hisashi

    2016-06-01

    Microfold (M) cells in the follicle-associated epithelium (FAE) of Peyer's patches contribute to the mucosal immune response by the transcytosis of microorganisms. The mechanism by which M cells take up microorganisms, and the functional proteins by which they do this, are not clear. In order to explore one such protein, we developed a 2H5-F3 monoclonal antibody (2H5-F3 mAb) through its binding to bovine M cells, and identified the antibody reactive molecule as cyclophilin A (Cyp-A). The localization patterns of Cyp-A were very similar to the localization pattern of cytokeratin (CK) 18-positive M cells. Cyp-A was identified at the luminal surface of CK18-positive M cells in bovine jejunal and ileal FAE. The membranous localization of Cyp-A in the bovine intestinal cell line (BIE cells) increased as cells differentiated toward M cells, as determined by flow cytometry analysis. Additionally, BIE cells released Cyp-A to the extracellular space and the differentiation of BIE cells to M cells increased the secretion of Cyp-A, as determined by western blotting. Accordingly, Cyp-A may be localized in M cells in the small intestinal epithelium of cattle. The rise of the membranous localization and secretion of Cyp-A by differentiation toward M cells indicates that Cyp-A has an important role in the function of M cells. While Cyp-A of the M cell membrane may contribute to the uptake of viruses with peptidyl-prolyl cis-trans isomerase activity, in the extracellular space Cyp-A may work as a chemokine and contribute to the distribution of immuno-competent cells.

  6. A2E induces IL-1ß production in retinal pigment epithelial cells via the NLRP3 inflammasome.

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    Owen A Anderson

    Full Text Available AIMS: With ageing extracellular material is deposited in Bruch's membrane, as drusen. Lipofuscin is deposited in retinal pigment epithelial cells. Both of these changes are associated with age related macular degeneration, a disease now believed to involve chronic inflammation at the retinal-choroidal interface. We hypothesise that these molecules may act as danger signals, causing the production of inflammatory chemokines and cytokines by the retinal pigment epithelium, via activation of pattern recognition receptors. METHODS: ARPE-19 cells were stimulated in vitro with the following reported components of drusen: amyloid-ß (1-42, Carboxyethylpyrrole (CEP modified proteins (CEP-HSA, Nε-(Carboxymethyllysine (CML modified proteins and aggregated vitronectin. The cells were also stimulated with the major fluorophore of lipofuscin: N-retinylidene-N-retinylethanolamine (A2E. Inflammatory chemokine and cytokine production was assessed using Multiplex assays and ELISA. The mechanistic evaluation of the NLRP3 inflammasome pathway was assessed in a stepwise fashion. RESULTS: Of all the molecules tested only A2E induced inflammatory chemokine and cytokine production. 25 µM A2E induced the production of significantly increased levels of the chemokines IL-8, MCP-1, MCG and MIP-1α, the cytokines IL-1ß, IL-2, IL-6, and TNF-α, and the protein VEGF-A. The release of IL-1ß was studied further, and was determined to be due to NLRP3 inflammasome activation. The pathway of activation involved endocytosis of A2E, and the three inflammasome components NLRP3, ASC and activated caspase-1. Immunohistochemical staining of ABCA4 knockout mice, which show progressive accumulation of A2E levels with age, showed increased amounts of IL-1ß proximal to the retinal pigment epithelium. CONCLUSIONS: A2E has the ability to stimulate inflammatory chemokine and cytokine production by RPE cells. The pattern recognition receptor NLRP3 is involved in this process. This

  7. Depression of Intraocular Pressure Following Inactivation of Connexin43 in the Nonpigmented Epithelium of the Ciliary Body

    Science.gov (United States)

    Calera, Mónica R.; Wang, Zhao; Sanchez-Olea, Roberto; Paul, David L.; Civan, Mortimer M.; Goodenough, Daniel A.

    2010-01-01

    Purpose Conditional inactivation of connexin43 (Cx43) in the pigmented epithelium of the mouse eye results in a reduction in aqueous humor production and complete loss of the vitreous chamber. It was proposed that gap junctions between pigmented and nonpigmented epithelia of the ciliary body are critical for the production of the aqueous humor. To form such junctions, Cx43 in the pigmented epithelium must interact with connexin(s) present in the adjacent cells of the nonpigmented epithelium. The importance of Cx43 expression in the nonpigmented epithelium for the establishment of gap junctions and the regulation of intraocular pressure was tested. Methods To inactivate Cx43 in the nonpigmented epithelium of the mouse eye, a mouse line was crossed with a floxed Cx43 locus (Cx43flox/flox) and a transgenic mouse line expressing cre recombinase under the control of the Pax6α promoter. General eye structure was evaluated by light microscopy, gap junctions were analyzed by electron microscopy, and intraocular pressure was directly assessed with micropipettes. Results In Pax6α-cre/Cx43flox/flox mice, Cx43 was partially inactivated in the nonpigmented epithelium of the ciliary body and iris. Animals developed dilatations between the pigmented and nonpigmented epithelia and displayed a significant reduction in intraocular pressure. However, gap junctions between the ciliary epithelial layers were decreased but not eliminated. Conclusions Cx43 expression in the nonpigmented epithelium of the ciliary body contributes to the formation of gap junctions with the cells of the pigmented epithelium. These gap junctions play a critical role in maintaining the physical integrity of the ciliary body epithelium. Although the partial loss of Cx43 from the nonpigmented epithelium was correlated with a measurable drop in intraocular pressure, possible changes in Cx43 in the aqueous outflow pathway may provide an additional contribution to the observed phenotype. PMID:19168903

  8. Trop2 marks transient gastric fetal epithelium and adult regenerating cells after epithelial damage.

    Science.gov (United States)

    Fernandez Vallone, Valeria; Leprovots, Morgane; Strollo, Sandra; Vasile, Gabriela; Lefort, Anne; Libert, Frederick; Vassart, Gilbert; Garcia, Marie-Isabelle

    2016-05-01

    Mouse fetal intestinal progenitors lining the epithelium prior to villogenesis grow as spheroids when cultured ex vivo and express the transmembrane glycoprotein Trop2 as a marker. Here, we report the characterization of Trop2-expressing cells from fetal pre-glandular stomach, growing as immortal undifferentiated spheroids, and their relationship with gastric development and regeneration. Trop2(+) cells generating gastric spheroids differed from adult glandular Lgr5(+) stem cells, but appeared highly related to fetal intestinal spheroids. Although they shared a common spheroid signature, intestinal and gastric fetal spheroid-generating cells expressed organ-specific transcription factors and were committed to intestinal and glandular gastric differentiation, respectively. Trop2 expression was transient during glandular stomach development, being lost at the onset of gland formation, whereas it persisted in the squamous forestomach. Undetectable under homeostasis, Trop2 was strongly re-expressed in glands after acute Lgr5(+) stem cell ablation or following indomethacin-induced injury. These highly proliferative reactive adult Trop2(+) cells exhibited a transcriptome displaying similarity with that of gastric embryonic Trop2(+) cells, suggesting that epithelium regeneration in adult stomach glands involves the partial re-expression of a fetal genetic program.

  9. Similar Squamous Cell Carcinoma Epithelium microRNA Expression in Never Smokers and Ever Smokers.

    Science.gov (United States)

    Kolokythas, Antonia; Zhou, Yalu; Schwartz, Joel L; Adami, Guy R

    2015-01-01

    The incidence of oral tumors in patients who never used mutagenic agents such as tobacco is increasing. In an effort to better understand these tumors we studied microRNA (miRNA) expression in tumor epithelium of never tobacco users, tumor epithelium of ever tobacco users, and nonpathological control oral epithelium. A comparison of levels among 372 miRNAs in 12 never tobacco users with oral squamous cell carcinoma (OSCC) versus 10 healthy controls was made using the reverse transcription quantitative polymerase chain reaction. A similar analysis was done with 8 ever tobacco users with OSCC. These comparisons revealed miR-10b-5p, miR-196a-5p, and miR-31-5p as enriched in the tumor epithelium in OSCC of both never and ever tobacco users. Examination of The Cancer Genome Atlas (TCGA) project miRNA data on 305 OSCCs and 30 controls revealed 100% of those miRNAs enriched in never smoker OSCCs in this patient group were also enriched in ever smoker OSCCs. Nonsupervised clustering of TCGA OSCCs was suggestive of two or four subgroups of tumors based on miRNA levels with limited evidence for differences in tobacco exposure among the groups. Results from both patient groups together stress the importance of miR196a-5p in OSCC malignancy in both never and ever smokers, and emphasize the overall similarity of miRNA expression in OSCCs in these two risk groups. It implies that there may be great similarity in etiology of OSCC in never and ever smokers and that classifying OSCC based on tobacco exposure may not be helpful in the clinic.

  10. Similar Squamous Cell Carcinoma Epithelium microRNA Expression in Never Smokers and Ever Smokers.

    Directory of Open Access Journals (Sweden)

    Antonia Kolokythas

    Full Text Available The incidence of oral tumors in patients who never used mutagenic agents such as tobacco is increasing. In an effort to better understand these tumors we studied microRNA (miRNA expression in tumor epithelium of never tobacco users, tumor epithelium of ever tobacco users, and nonpathological control oral epithelium. A comparison of levels among 372 miRNAs in 12 never tobacco users with oral squamous cell carcinoma (OSCC versus 10 healthy controls was made using the reverse transcription quantitative polymerase chain reaction. A similar analysis was done with 8 ever tobacco users with OSCC. These comparisons revealed miR-10b-5p, miR-196a-5p, and miR-31-5p as enriched in the tumor epithelium in OSCC of both never and ever tobacco users. Examination of The Cancer Genome Atlas (TCGA project miRNA data on 305 OSCCs and 30 controls revealed 100% of those miRNAs enriched in never smoker OSCCs in this patient group were also enriched in ever smoker OSCCs. Nonsupervised clustering of TCGA OSCCs was suggestive of two or four subgroups of tumors based on miRNA levels with limited evidence for differences in tobacco exposure among the groups. Results from both patient groups together stress the importance of miR196a-5p in OSCC malignancy in both never and ever smokers, and emphasize the overall similarity of miRNA expression in OSCCs in these two risk groups. It implies that there may be great similarity in etiology of OSCC in never and ever smokers and that classifying OSCC based on tobacco exposure may not be helpful in the clinic.

  11. Retinoic acid signaling regulates Krt5 and Krt14 independently of stem cell markers in submandibular salivary gland epithelium.

    Science.gov (United States)

    Abashev, Timur M; Metzler, Melissa A; Wright, Diana M; Sandell, Lisa L

    2017-02-01

    Retinoic acid (RA), the active metabolite of vitamin A, has been demonstrated to be important for growth and branching morphogenesis of mammalian embryonic salivary gland epithelium. However, it is not known whether RA functions directly within epithelial cells or in associated tissues that influence morphogenesis of salivary epithelium. Moreover, downstream targets of RA regulation have not been identified. Here, we show that canonical RA signaling occurs in multiple tissues of embryonic mouse salivary glands, including epithelium, associated parasympathetic ganglion neurons, and nonneuronal mesenchyme. By culturing epithelium explants in isolation from other tissues, we demonstrate that RA influences epithelium morphogenesis by direct action in that tissue. Moreover, we demonstrate that inhibition of RA signaling represses cell proliferation and expression of FGF10 signaling targets, and upregulates expression of basal epithelial keratins Krt5 and Krt14. Importantly, we show that the stem cell gene Kit is regulated inversely from Krt5/Krt14 by RA signaling. RA regulates Krt5 and Krt14 expression independently of stem cell character in developing salivary epithelium. RA, or chemical inhibitors of RA signaling, could potentially be used for modulating growth and differentiation of epithelial stem cells for the purpose of re-populating damaged glands or generating bioengineered organs. Developmental Dynamics 246:135-147, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. The Bacillus thuringiensis vegetative insecticidal protein Vip3A lyses midgut epithelium cells of susceptible insects.

    Science.gov (United States)

    Yu, C G; Mullins, M A; Warren, G W; Koziel, M G; Estruch, J J

    1997-02-01

    The Vip3A protein is a member of a newly discovered class of vegetative insecticidal proteins with activity against a broad spectrum of lepidopteran insects. Histopathological observations indicate that Vip3A ingestion by susceptible insects such as the black cutworm (Agrotis ipsilon) and fall armyworm (Spodoptera frugiperda) causes gut paralysis at concentrations as low as 4 ng/cm2 of diet and complete lysis of gut epithelium cells resulting in larval death at concentrations above 40 ng/cm2. The European corn borer (Ostrinia nubilalis), a nonsusceptible insect, does not develop any pathology upon ingesting Vip3A. While proteolytic processing of the Vip3A protein by midgut fluids obtained from susceptible and nonsusceptible insects is comparable, in vivo immunolocalization studies show that Vip3a binding is restricted to gut cells of susceptible insects. Therefore, the insect host range for Vip3A seems to be determined by its ability to bind gut cells. These results indicate that midgut epithelium cells of susceptible insects are the primary target for the Vip3A insecticidal protein and that their subsequent lysis is the primary mechanism of lethality. Disruption of gut cells appears to be the strategy adopted by the most effective insecticidal proteins.

  13. Airway responses towards allergens - from the airway epithelium to T cells.

    Science.gov (United States)

    Papazian, D; Hansen, S; Würtzen, P A

    2015-08-01

    The prevalence of allergic diseases such as allergic rhinitis is increasing, affecting up to 30% of the human population worldwide. Allergic sensitization arises from complex interactions between environmental exposures and genetic susceptibility, resulting in inflammatory T helper 2 (Th2) cell-derived immune responses towards environmental allergens. Emerging evidence now suggests that an epithelial dysfunction, coupled with inherent properties of environmental allergens, can be responsible for the inflammatory responses towards allergens. Several epithelial-derived cytokines, such as thymic stromal lymphopoietin (TSLP), IL-25 and IL-33, influence tissue-resident dendritic cells (DCs) as well as Th2 effector cells. Exposure to environmental allergens does not elicit Th2 inflammatory responses or any clinical symptoms in nonatopic individuals, and recent findings suggest that a nondamaged, healthy epithelium lowers the DCs' ability to induce inflammatory T-cell responses towards allergens. The purpose of this review was to summarize the current knowledge on which signals from the airway epithelium, from first contact with inhaled allergens all the way to the ensuing Th2-cell responses, influence the pathology of allergic diseases.

  14. Global expression profiling of globose basal cells and neurogenic progression within the olfactory epithelium.

    Science.gov (United States)

    Krolewski, Richard C; Packard, Adam; Schwob, James E

    2013-03-01

    Ongoing, lifelong neurogenesis maintains the neuronal population of the olfactory epithelium in the face of piecemeal neuronal turnover and restores it following wholesale loss. The molecular phenotypes corresponding to different stages along the progression from multipotent globose basal cell (GBC) progenitor to differentiated olfactory sensory neuron are poorly characterized. We used the transgenic expression of enhanced green fluorescent protein (eGFP) and cell surface markers to FACS-isolate ΔSox2-eGFP(+) GBCs, Neurog1-eGFP(+) GBCs and immature neurons, and ΔOMP-eGFP(+) mature neurons from normal adult mice. In addition, the latter two populations were also collected 3 weeks after olfactory bulb ablation, a lesion that results in persistently elevated neurogenesis. Global profiling of mRNA from the populations indicates that all stages of neurogenesis share a cohort of >2,100 genes that are upregulated compared to sustentacular cells. A further cohort of >1,200 genes are specifically upregulated in GBCs as compared to sustentacular cells and differentiated neurons. The increased rate of neurogenesis caused by olfactory bulbectomy had little effect on the transcriptional profile of the Neurog1-eGFP(+) population. In contrast, the abbreviated lifespan of ΔOMP-eGFP(+) neurons born in the absence of the bulb correlated with substantial differences in gene expression as compared to the mature neurons of the normal epithelium. Detailed examination of the specific genes upregulated in the different progenitor populations revealed that the chromatin modifying complex proteins LSD1 and coREST were expressed sequentially in upstream ΔSox2-eGFP(+) GBCs and Neurog1-eGFP(+) GBCs/immature neurons. The expression patterns of these proteins are dynamically regulated after activation of the epithelium by methyl bromide lesion.

  15. Asthmatic bronchial epithelium activated by the proteolytic allergen Der p 1 increases selective dendritic cell recruitment.

    Science.gov (United States)

    Pichavant, Muriel; Charbonnier, Anne-Sophie; Taront, Solenne; Brichet, Anne; Wallaert, Benoît; Pestel, Joel; Tonnel, André-Bernard; Gosset, Philippe

    2005-04-01

    Airway dendritic cells (DCs) are crucial for allergen-induced sensitization and inflammation in allergic asthma. After allergen challenge, an increased number of DCs is observed in airway epithelium from patients with allergy. Because Der p 1, a cysteine protease allergen from Dermatophagoides pteronyssinus , induces chemokine production by bronchial epithelial cells (BECs), the purpose of this investigation was to evaluate the capacity of BEC exposed to Der p 1 to recruit DCs. Chemotactic activity of BEAS-2B, a bronchial epithelial cell line, and BECs from nonatopic controls and patients with allergic asthma was evaluated on the migration of precursors, immature and mature monocyte-derived DCs (MDDCs), and CD34 + -derived Langerhans cells (LCs). C-C chemokine ligand (CCL)-2, CCL5, and C-X-C chemokine ligand 10 production by BEAS-2B and BEC was increased after Der p 1 exposure, whereas the proenzyme proDer p 1 devoid of enzymatic activity had no effect. Der p 1 stimulation of BEAS-2B and BEC from both groups increased significantly the recruitment of MDDC precursors, depending on CCL2, CCL5, and C-X-C chemokine ligand 10 production. In a reconstituted polarized epithelium, apical application of Der p 1 enhanced MDDC precursor migration into the epithelial layer. Moreover, Der p 1 stimulation of BEC from patients with asthma but not from controls increased the migration of LC precursors, mainly dependent on CCL20 secretion. No migration of immature and mature DCs was observed. These data confirmed that BECs participate in the homeostasis of the DC network present within the bronchial epithelium through the secretion of chemokines. In allergic asthma, upregulation of CCL20 production induced LC recruitment, the role of which remains to be determined.

  16. Photocurrent generation by dye-sensitized solar cells using natural pigments.

    Science.gov (United States)

    Armendáriz-Mireles, Eddie Nahúm; Rocha-Rangel, Enrique; Caballero-Rico, Frida; Ramírez-de-León, José Alberto; Vázquez, Manuel

    2017-01-01

    The development of photovoltaic panels has improved the conversion of solar radiation into electrical energy. This paper deals with the electrical and thermal characteristics (voltage, current, and temperature) of photovoltaic solar cells sensitized with natural pigments (dye-sensitized solar cell, DSSC) based on a titanium dioxide semiconductor. Several natural pigments (blackberry, beets, eggplant skin, spinach, flame tree flower, papaya leaf, and grass extracts) were evaluated to determine their sensitizing effect on titanium dioxide. The results showed the great potential of natural pigments for use in solar cells. The best results were obtained with the blackberry pigment, reaching a value of 7.1 mA current, open-circuit voltage (Voc ) of 0.72 V in 2 cm(2) , and fill factor (ff) of 0.51 in the DSSC. This performance is well above than that currently offers by actual cells.

  17. Puerarin antagonizes peroxyntrite-induced injury in retinal pigment epithelial cells

    Institute of Scientific and Technical Information of China (English)

    Lina Hao; Xudong Zhang; Tao Yang; Junling Ma

    2012-01-01

    A rat model of diabetes mellitus was established by intraperitoneal injection of streptozotocin. Three days later, the rats were intraperitoneally administered 140 mg puerarin/kg daily, for a total of 60 successive days. DNA ladder results showed increased apoptosis over time in retinal pigment epithelial cells from rats with streptozotocin-induced diabetes mellitus. Western blot analysis, Reverse transcription-PCR, immunohistochemistry, and flow cytometry results showed increased expression of 3-nitrotyrosine, a peroxyntrite marker, as well as inducible nitric synthase and Fas/FasL, in retinal pigment epithelial cells. Puerarin reversed these changes, and results demonstrated that puerarin inhibited Fas/FasL expression and alleviated peroxyntrite injury to retinal pigment epithelial cells. These results suggested that puerarin inhibited production of inducible nitric oxide synthase and directly antagonized peroxyntrite injury in retinal pigment epithelial cells.

  18. A HEARTWOOD PIGMENT IN DALBERGIA CELL CULTURES. (R827612E02)

    Science.gov (United States)

    In an extensive survey of the genera Baphia, Caesalpinia, Dalbergia, Haematoxylon, and Pterocarpus, we have identified a number of species whose cell cultures accumulated pigments similar to those in heartwood. Thirteen rosewood (Dalbergia) species produce...

  19. Multiple pigment cell types contribute to the black, blue, and orange ornaments of male guppies (Poecilia reticulata).

    Science.gov (United States)

    Kottler, Verena A; Koch, Iris; Flötenmeyer, Matthias; Hashimoto, Hisashi; Weigel, Detlef; Dreyer, Christine

    2014-01-01

    The fitness of male guppies (Poecilia reticulata) highly depends on the size and number of their black, blue, and orange ornaments. Recently, progress has been made regarding the genetic mechanisms underlying male guppy pigment pattern formation, but we still know little about the pigment cell organization within these ornaments. Here, we investigate the pigment cell distribution within the black, blue, and orange trunk spots and selected fin color patterns of guppy males from three genetically divergent strains using transmission electron microscopy. We identified three types of pigment cells and found that at least two of these contribute to each color trait. Further, two pigment cell layers, one in the dermis and the other in the hypodermis, contribute to each trunk spot. The pigment cell organization within the black and orange trunk spots was similar between strains. The presence of iridophores in each of the investigated color traits is consistent with a key role for this pigment cell type in guppy color pattern formation.

  20. The 5HT1a receptor agonist 8-Oh DPAT induces protection from lipofuscin accumulation and oxidative stress in the retinal pigment epithelium.

    Directory of Open Access Journals (Sweden)

    Prajitha Thampi

    Full Text Available Age-related macular degeneration (AMD, a major cause of blindness in the elderly, is associated with oxidative stress, lipofuscin accumulation and retinal degeneration. The aim of this study was to determine if a 5-HT(1A receptor agonist can reduce lipofuscin accumulation, reduce oxidative damage and prevent retinal cell loss both in vitro and in vivo. Autophagy-derived and photoreceptor outer segment (POS-derived lipofuscin formation was assessed using FACS analysis and confocal microscopy in cultured retinal pigment epithelial (RPE cells in the presence or absence of the 5-HT(1A receptor agonist, 8-OH DPAT. 8-OH DPAT treatment resulted in a dose-dependent reduction in both autophagy- and POS-derived lipofuscin compared to control. Reduction in autophagy-induced lipofuscin was sustained for 4 weeks following removal of the drug. The ability of 8-OH DPAT to reduce oxidative damage following exposure to 200 µM H(2O(2 was assessed. 8-OH DPAT reduced superoxide generation and increased mitochondrial superoxide dismutase (MnSOD levels and the ratio of reduced glutathione to the oxidized form of glutathione in H(2O(2-treated cells compared to controls and protected against H(2O(2-initiated lipid peroxidation, nitrotyrosine levels and mitochondrial damage. SOD2 knockdown mice, which have an AMD-like phenotype, received daily subcutaneous injections of either saline, 0.5 or 5.0 mg/kg 8-OH DPAT and were evaluated at monthly intervals. Systemic administration of 8-OH DPAT improved the electroretinogram response in SOD2 knockdown eyes of mice compared to knockdown eyes receiving vehicle control. There was a significant increase in the ONL thickness in mice treated with 8-OH DPAT at 4 months past the time of MnSOD knockdown compared to untreated controls together with a 60% reduction in RPE lipofuscin. The data indicate that 5-HT(1A agonists can reduce lipofuscin accumulation and protect the retina from oxidative damage and mitochondrial dysfunction. 5-HT

  1. Dynamic T cell migration program provides resident memory within intestinal epithelium

    Science.gov (United States)

    Choo, Daniel; Vezys, Vaiva; Wherry, E. John; Duraiswamy, Jaikumar; Akondy, Rama; Wang, Jun; Casey, Kerry A.; Barber, Daniel L.; Kawamura, Kim S.; Fraser, Kathryn A.; Webby, Richard J.; Brinkmann, Volker; Butcher, Eugene C.; Newell, Kenneth A.

    2010-01-01

    Migration to intestinal mucosa putatively depends on local activation because gastrointestinal lymphoid tissue induces expression of intestinal homing molecules, whereas skin-draining lymph nodes do not. This paradigm is difficult to reconcile with reports of intestinal T cell responses after alternative routes of immunization. We reconcile this discrepancy by demonstrating that activation within spleen results in intermediate induction of homing potential to the intestinal mucosa. We further demonstrate that memory T cells within small intestine epithelium do not routinely recirculate with memory T cells in other tissues, and we provide evidence that homing is similarly dynamic in humans after subcutaneous live yellow fever vaccine immunization. These data explain why systemic immunization routes induce local cell-mediated immunity within the intestine and indicate that this tissue must be seeded with memory T cell precursors shortly after activation. PMID:20156972

  2. Regulation of molecular clock oscillations and phagocytic activity via muscarinic Ca2+ signaling in human retinal pigment epithelial cells

    Science.gov (United States)

    Ikarashi, Rina; Akechi, Honami; Kanda, Yuzuki; Ahmad, Alsawaf; Takeuchi, Kouhei; Morioka, Eri; Sugiyama, Takashi; Ebisawa, Takashi; Ikeda, Masaaki; Ikeda, Masayuki

    2017-01-01

    Vertebrate eyes are known to contain circadian clocks, however, the intracellular mechanisms regulating the retinal clockwork remain largely unknown. To address this, we generated a cell line (hRPE-YC) from human retinal pigmental epithelium, which stably co-expressed reporters for molecular clock oscillations (Bmal1-luciferase) and intracellular Ca2+ concentrations (YC3.6). The hRPE-YC cells demonstrated circadian rhythms in Bmal1 transcription. Also, these cells represented circadian rhythms in Ca2+-spiking frequencies, which were canceled by dominant-negative Bmal1 transfections. The muscarinic agonist carbachol, but not photic stimulation, phase-shifted Bmal1 transcriptional rhythms with a type-1 phase response curve. This is consistent with significant M3 muscarinic receptor expression and little photo-sensor (Cry2 and Opn4) expression in these cells. Moreover, forskolin phase-shifted Bmal1 transcriptional rhythm with a type-0 phase response curve, in accordance with long-lasting CREB phosphorylation levels after forskolin exposure. Interestingly, the hRPE-YC cells demonstrated apparent circadian rhythms in phagocytic activities, which were abolished by carbachol or dominant-negative Bmal1 transfection. Because phagocytosis in RPE cells determines photoreceptor disc shedding, molecular clock oscillations and cytosolic Ca2+ signaling may be the driving forces for disc-shedding rhythms known in various vertebrates. In conclusion, the present study provides a cellular model to understand molecular and intracellular signaling mechanisms underlying human retinal circadian clocks. PMID:28276525

  3. Effects of aging on mouse tongue epithelium focusing on cell proliferation rate and morphological aspects.

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    Carrard, Vinicius Coelho; Pires, Aline Segatto; Badauy, Cristiano Macabu; Rados, Pantelis Varvaki; Lauxen, Isabel Silva; Sant'Ana Filho, Manoel

    2008-11-01

    The aim of this study was to investigate cell proliferation rate and certain morphological features of mouse epithelium as aging progresses. Tongue biopsies were performed on female mice (Mus domesticus domesticus) at 2, 8, 14 and 20 months of age as indicative of adolescence, adulthood, early senescence and senescence, respectively. Histological sections of tongue were stained with hematoxylin-eosin and subjected to silver staining for active nucleolar organizer region counting. Cell proliferation rate and epithelial thickness analysis were carried out. Analysis of variance detected no differences between the groups in terms of numbers of silver-stained dots associated with nucleolar proteins. There was an increase in mean epithelial thickness in adult animals, followed by a gradual reduction until senescence. Mean keratin thickness presented an increase at 8 and 20 months of age. This difference is probably related to puberty, growth or dietary habits. Aging has no influence on oral epithelial proliferation rate in mice. A gradual reduction in epithelial thickness is a feature of aging in mammals. A conspicuous increase in the keratin layer was observed in senescence as an adaptative response to the reduction in epithelial thickness. These results suggest that aging affects the oral epithelium maturation process through a mechanism that is not related to cell proliferation.

  4. Vitamin D reduces the inflammatory response by Porphyromonas gingivalis infection by modulating human β-defensin-3 in human gingival epithelium and periodontal ligament cells.

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    De Filippis, Anna; Fiorentino, Margherita; Guida, Luigi; Annunziata, Marco; Nastri, Livia; Rizzo, Antonietta

    2017-04-03

    Periodontitis is a multifactorial polymicrobial infection characterized by a destructive inflammatory process. Porphyromonas gingivalis, a Gram-negative black-pigmented anaerobe, is a major pathogen in the initiation and progression of periodontitis; it produces several virulence factors that stimulate human gingival epithelium (HGE) cells and human periodontal ligament (HPL) cells to produce various inflammatory mediators. A variety of substances, such as vitamin D, have growth-inhibitory effects on some bacterial pathogens and have shown chemo-preventive and anti-inflammatory activity. We used a model with HGE and HPL cells infected with P. gingivalis to determine the influence of vitamin D on P. gingivalis growth and adhesion and the immunomodulatory effect on TNF-α, IL-8, IL-12 and human-β-defensin 3 production. Our results demonstrated, firstly, the lack of any cytotoxic effect on the HGE and HPL cells when treated with vitamin D; in addition, vitamin D inhibited P. gingivalis adhesion and infectivity in HGE and HPL cells. Our study then showed that vitamin D reduced TNF-α, IL-8, IL-12 production in P. gingivalis-infected HGE and HPL cells. In contrast, a significant upregulation of the human-β-defensin 3 expression in HGE and HPL cells induced by P. gingivalis was demonstrated. Our results indicate that vitamin D specifically enhances the production of the human-β-defensin 3 antimicrobial peptide and exerts an inhibitory effect on the pro-inflammatory cytokines, thus suggesting that vitamin D may offer possible therapeutic applications for periodontitis.

  5. The cell biology of the intestinal epithelium and its relation to inflammatory bowel disease.

    Science.gov (United States)

    Deuring, J Jasper; de Haar, Colin; Kuipers, Ernst J; Peppelenbosch, Maikel P; van der Woude, C Janneke

    2013-04-01

    The epithelial layer of our intestines must meet two opposing requirements. On one hand it must allow for efficient uptake of nutrients and fluids, on the other hand it is a vital defence barrier between the milieu interior and the milieu exterior. In contrast to the lung that by virtue of cilia movement is kept virtually sterile, the gut epithelium is confronted by a stupendous microbiological load and a substantial xenobiotic challenge. The efficiency by which our intestinal epithelium manages to deal with the challenge of efficient nutrient absorption while simultaneously fulfilling its barrier function is testimony to what the forces of evolution can accomplish. Importantly, our understanding as to how our gut epithelial compartment manages this balancing act is now rapidly emerging, answering one of the oldest questions in cell biology. Importantly, when aberrations in this balance occur, for instance as a consequence genetic polymorphisms, increased propensity to develop chronic inflammation and inflammatory bowel disease is the result. Thus the knowledge on intestinal cell biology and biochemistry is not only of academic interest but may also aid design of novel avenues for the rational treatment of mucosal disease.

  6. The inhibitory effect of pigment epithelium-derived factor on migration of gliomas%色素上皮细胞衍生因子与胶质瘤侵袭的相关性

    Institute of Scientific and Technical Information of China (English)

    张伎; 关明; 吕元

    2008-01-01

    目的 评价色素上皮细胞衍生因子(PEDF)对胶质瘤侵袭的抑制作用.方法 将PEDF(100 ng/ml)加入胶质瘤细胞U87中(U87PEDF),以未加PEDF蛋白的胶质瘤细胞作对照组(U87con),同时在U87PEDF中加入0.25μg/ml的促血管生成因子(VEGF,U87PEDF+VEGF).细胞迁徙实验检测PEDF抑制胶质瘤细胞侵袭性;实时荧光定量逆转录(RT)-PCR检测层粘连蛋白Laminin-8表达.结果 迁徙实验结果表明,对照组胶质瘤细胞穿透数明显多于PEDF处理组细胞,加入VEGF后,胶质瘤细胞迁徙率的抑制率仍减少38%;实时荧光定量RT-PCR结果显示,U87对照组 Laminin-8α4、β1、γlmRAN表达分别为(1.043±0.090)、(0.823±0.012)、(0.762±0.005)拷贝/μl,明显高于U87PEDF组[(0.633±0.004)、(0.442±0.005)、(0.424±0.002)拷贝/μl,P<0.05].结论 在VEGF存在的条件下,PEDF能有效抑制胶质瘤细胞的迁徙,表明其可能由下调Laminin-8基因的表达所致.%Objective To assess the impact of pigment epithelium-derived factor(PEDF) on the migration of the glioma cells.Methods PEDF(100 ng/ml)was added to U87 cells(U87PFDF),and VEGF of 0.25μg/ml was added to U87PEDF+VEGF while U87 cells as control(U87con).The cell migratory assav was used tbr evaluating its inhibitory migration rate of PEDF.Real time RT-PCR was used for evaluating the expression of Laminin-8 gene.Results The number of migratory cells was higher than those with added PEDF,and the inhibitory rate of migratory was 38% even in the presence of VEGF.Real time RT-PCR revealed that the mRNA expression levels of α4,β1,γl were(1.043±0.090),(0.823±0.012).(0.762±0.05) copy/μl,which were higher than those treated by PEDF(0.633±0.004),(0.442±0.005).(0.424±0.002)copy/μl,respectively (P<0.05).Conclusion PEDF could decrease the migmtory capacity of the glioma cells even in the presence of VEGF because of the regulation of Laminin-8 in part.

  7. Cell proliferation of esophageal squamous epithelium in erosive and non-erosive reflux disease

    Institute of Scientific and Technical Information of China (English)

    Carlo Calabrese; Davide Trerè; Lorenzo Montanaro; Giuseppina Liguori; Elisa Brighenti; Mauela Vici; Paolo Gionchetti; Fernando Rizzello; Massimo Campieri; Massimo Derenzini

    2011-01-01

    AIM: To elucidate cell proliferation in erosive reflux disease (ERD) and non-erosive reflux disease (NERD), we evaluated markers in squamous epithelial cells. METHODS: Thirty-four consecutive patients with gastroesophageal- reflux-disease-related symptoms (21 NERD and 13 ERD) were evaluated for the enrolment into the study. All patients underwent 24-h pH monitoring, standard endoscopy, and biopsy for histological evaluation. The expression of cyclins D and A was evaluated by real-time reverse transcription polymerase chain reaction (RT-PCR) from isolated epithelial cells. In all samples, analysis of the isolated cell population revealed the presence of epithelial cells only. RESULTS: Real-time RT-PCR showed that, in patients with ERD, the relative expression of cyclin D1 mRNA in esophageal epithelium was strongly decreased in comparison with NERD patients. The mean value of relative expression of cyclin D1 mRNA in NERD patients was 3.44 ± 1.9, whereas in ERD patients, it was 1.32 ± 0.87 (P = 0.011). Real-time RT-PCR showed that, in patients with ERD, relative expression of cyclin A mRNA in esophageal epithelium was decreased in comparison with that in NERD patients (2.31 ± 2.87 vs 0.66 ± 1.11). The mean bromodeoxyuridine labeling index in the NERD patients was 5.42% ± 1.68%, whereas in ERD patients, it was 4.3% ± 1.59%. CONCLUSION: We confirmed reduced epithelial proliferation in ERD compared with NERD patients, and that individuals who develop ERD are characterized by weaker epithelial cell proliferation.

  8. Organ culture-cell culture system for studying multistage carcinogenesis in respiratory epithelium. [Mice

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    Steele, Vernon E.; Marchok, Ann C.; Nettesheim, Paul

    1977-01-01

    An organ culture-cell culture system was used to demonstrate carcinogen dose-dependent transformation of tracheal epithelial cells in vitro. Tracheal explants were exposed to MNNG (N-methyl-N/sup 1/-nitro-N-nitrosoguanidine) in organ culture. Outgrowths from these explants provided epithelial cell cultures. The numbers of long term epithelial cell cultures and cell lines that were established per explant increased as MNNG exposure concentration increased. At the present time, more cell lines derived from explants exposed to the highest MNNG concentration have produced palpable tumors than cell lines derived from explants exposed to lower MNNG concentrations. No cell lines were established from primaries derived from control explants. TPA (12-0-tetradecanoyl-phorbol-13-acetate), stimulates DNA synthesis in tracheal epithelium in organ culture in a manner simular to that described for mouse skin. Short exposures to TPA not only stimulated DNA synthesis earlier, but the stimulation was greater than that obtained with continuous exposure. At the present time, exposure of tracheal organ cultures to MNNG followed by TPA has resulted in an enhanced production of morphologically altered cells in primary epithelial cell cultures, than exposure to either agent alone.

  9. Derivation of neurons with functional properties from adult limbal epithelium: implications in autologous cell therapy for photoreceptor degeneration.

    Science.gov (United States)

    Zhao, Xing; Das, Ani V; Bhattacharya, Sumitra; Thoreson, Wallace B; Sierra, Jorge Rodriguez; Mallya, Kavita B; Ahmad, Iqbal

    2008-04-01

    The limbal epithelium (LE), a circular and narrow epithelium that separates cornea from conjunctiva, harbors stem cells/progenitors in its basal layer that regenerate cornea. We have previously demonstrated that cells in the basal LE, when removed from their niche and cultured in reduced bond morphogenetic protein signaling, acquire properties of neural progenitors. Here, we demonstrate that LE-derived neural progenitors generate neurons with functional properties and can be directly differentiated along rod photoreceptor lineage in vitro and in vivo. These observations posit the LE as a potential source of neural progenitors for autologous cell therapy to treat photoreceptor degeneration in age-related macular degeneration and retinitis pigmentosa.

  10. Tissue engineering and the use of stem/progenitor cells for airway epithelium repair

    Directory of Open Access Journals (Sweden)

    GM Roomans

    2010-06-01

    Full Text Available Stem/progenitor cells can be used to repair defects in the airway wall, resulting from e.g., tumors, trauma, tissue reactions following long-time intubations, or diseases that are associated with epithelial damage. Several potential sources of cells for airway epithelium have been identified. These can be divided into two groups. The first group consists of endogenous progenitor cells present in the respiratory tract. This group can be subdivided according to location into (a a ductal cell type in the submucosal glands of the proximal trachea, (b basal cells in the intercartilaginous zones of the lower trachea and bronchi, (c variant Clara cells (Clarav-cells in the bronchioles and (d at the junctions between the bronchioles and the alveolar ducts, and (e alveolar type II cells. This classification of progenitor cell niches is, however, controversial. The second group consists of exogenous stem cells derived from other tissues in the body. This second group can be subdivided into: (a embryonic stem (ES cells, induced pluripotent stem (iPS cells, or amniotic fluid stem cells, (b side-population cells from bone marrow or epithelial stem cells present in bone marrow or circulation and (c fat-derived mesenchymal cells. Airway epithelial cells can be co-cultured in a system that includes a basal lamina equivalent, extracellular factors from mesenchymal fibroblasts, and in an air-liquid interface system. Recently, spheroid-based culture systems have been developed. Several clinical applications have been suggested: cystic fibrosis, acute respiratory distress syndrome, chronic obstructive lung disease, pulmonary fibrosis, pulmonary edema, and pulmonary hypertension. Clinical applications so far are few, but include subglottic stenosis, tracheomalacia, bronchiomalacia, and emphysema.

  11. Dynamics of planar cell polarity protein Vangl2 in the mouse oviduct epithelium.

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    Shi, Dongbo; Usami, Fumiko; Komatsu, Kouji; Oka, Sanae; Abe, Takaya; Uemura, Tadashi; Fujimori, Toshihiko

    2016-08-01

    The planar cell polarity (PCP) pathway regulates morphogenesis in various organs. The polarized localization is a key feature of core PCP factors for orchestrating cell polarity in an epithelial sheet. Several studies using Drosophila melanogaster have investigated the mechanism of the polarized localization. However, to what extent these mechanisms are conserved and how the polarization of core PCP factors is maintained in mature vertebrates are still open questions. Here, we addressed these questions by analyzing the dynamics of Vangl2, a member of core PCP factors, in the mouse oviduct epithelium. Multiple core PCP factors including Vangl2 were expressed in the mouse oviduct in postnatal stages. Vangl1, Vangl2 and Frizzled6 had polarized localization in the oviduct epithelium. Exogenously introduced expression of green fluorescent protein (GFP)-tagged core PCP factors by electroporation revealed that Vangl1, Vangl2 and Prickle2 are localized on the ovarian side of the cell periphery in the oviduct. To visualize the Vangl2 dynamics, we generated the R26-Vangl2-EGFP transgenic mice. In these mice, Vangl2-EGFP was ubiquitously expressed and showed polarized localization in multiple organs including the oviduct, the trachea, the lateral ventricle and the uterus. Fluorescence recovery after photobleaching (FRAP) analysis in the mature oviduct revealed that Vangl2 in the enriched subdomain of cell periphery (cellular edge) was more stable than Vangl2 in the less-enriched cellular edge. Furthermore, when a subregion of a Vangl2-enriched cellular edge was bleached, the Vangl2-enriched subregion neighboring the bleached region in the same cellular edge tended to decrease more intensities than the neighboring sub-region in the next Vangl2-enriched cellular edge. Finally, the polarization of Vangl2 was observed in nocodazole treated mouse viduct, suggesting the maintenance of Vangl2 asymmetry is independent of microtubule formation. Taken together, we revealed the

  12. Thermosensitive chitosan-based hydrogels releasing stromal cell derived factor-1 alpha recruit MSC for corneal epithelium regeneration.

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    Tang, Qiaomei; Luo, Chenqi; Lu, Bing; Fu, Qiuli; Yin, Houfa; Qin, Zhenwei; Lyu, Danni; Zhang, Lifang; Fang, Zhi; Zhu, Yanan; Yao, Ke

    2017-10-01

    Corneal epithelium integrity depends on continuous self-renewing of epithelium and connections between adjacent cells or between the cells and the basement membrane. Self-renewing epithelium cells mainly arise from the continuous proliferation and differentiation of the basal layer and limbal stem cells. The aim of the present study was to generate a bioactive, thermosensitive chitosan-gelatin hydrogel (CHI hydrogel) by incorporating exogenous recombinant human stromal cell-derived factor-1 alpha (SDF-1 alpha) for corneal epithelium regeneration. The exogenous SDF-1 alpha could enhance the stem cells proliferation, chemotaxis and migration, and the expression levels of related genes were significantly elevated in LESCs and mesenchymal stem cells (MSCs) in vitro. Moreover, the MSCs promoted the proliferation and maintained the corneal fate of the LESCs. The rat alkali injury model was used for in vivo study. The injured eyes were covered with CHI hydrogel alone or rhSDF-1 alpha-loaded CHI hydrogel. All rats were followed for 13days. Histological examination showed that the SDF-1 alpha/CHI hydrogel complex group had a nearly normal thickness; moreover, it was also found that this group could upregulate the expression of some genes and had more ΔNp63-positive cells. The SDF-1 alpha/CHI hydrogel complex group had a more tightly arranged epithelium compared with the control group using transmission electron microscopy (TEM). The mechanism for this may have involved the activation of stem cell homing and the secretion of growth factors via the SDF-1/CXCR4 chemokine axis. Therefore, SDF-1 alpha/CHI hydrogel complexes could provide a new idea for the clinical application. The clarity of cornea is important for normal vision. The loss or dysfunction of LESCs leads to the impairment of corneal epithelium. The complete regeneration of corneal epithelium has not been achieved. Our study demonstrated that the incorporation of rhSDF-1 alpha with CHI hydrogel accelerated corneal

  13. In vitro ultraviolet–induced damage in human corneal, lens, and retinal pigment epithelial cells

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    Youn, Hyun-Yi; McCanna, David J.; Sivak, Jacob G.; Jones, Lyndon W.

    2011-01-01

    Purpose The purpose was to develop suitable in vitro methods to detect ocular epithelial cell damage when exposed to UV radiation, in an effort to evaluate UV-absorbing ophthalmic biomaterials. Methods Human corneal epithelial cells (HCEC), lens epithelial cells (HLEC), and retinal pigment epithelial cells (ARPE-19) were cultured and Ultraviolet A/Ultraviolet B (UVA/UVB) blocking filters and UVB-only blocking filters were placed between the cells and a UV light source. Cells were irradiated w...

  14. Reconstructing lineage hierarchies of the distal lung epithelium using single-cell RNA-seq.

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    Treutlein, Barbara; Brownfield, Doug G; Wu, Angela R; Neff, Norma F; Mantalas, Gary L; Espinoza, F Hernan; Desai, Tushar J; Krasnow, Mark A; Quake, Stephen R

    2014-05-15

    The mammalian lung is a highly branched network in which the distal regions of the bronchial tree transform during development into a densely packed honeycomb of alveolar air sacs that mediate gas exchange. Although this transformation has been studied by marker expression analysis and fate-mapping, the mechanisms that control the progression of lung progenitors along distinct lineages into mature alveolar cell types are still incompletely known, in part because of the limited number of lineage markers and the effects of ensemble averaging in conventional transcriptome analysis experiments on cell populations. Here we show that single-cell transcriptome analysis circumvents these problems and enables direct measurement of the various cell types and hierarchies in the developing lung. We used microfluidic single-cell RNA sequencing (RNA-seq) on 198 individual cells at four different stages encompassing alveolar differentiation to measure the transcriptional states which define the developmental and cellular hierarchy of the distal mouse lung epithelium. We empirically classified cells into distinct groups by using an unbiased genome-wide approach that did not require a priori knowledge of the underlying cell types or the previous purification of cell populations. The results confirmed the basic outlines of the classical model of epithelial cell-type diversity in the distal lung and led to the discovery of many previously unknown cell-type markers, including transcriptional regulators that discriminate between the different populations. We reconstructed the molecular steps during maturation of bipotential progenitors along both alveolar lineages and elucidated the full life cycle of the alveolar type 2 cell lineage. This single-cell genomics approach is applicable to any developing or mature tissue to robustly delineate molecularly distinct cell types, define progenitors and lineage hierarchies, and identify lineage-specific regulatory factors.

  15. Transcriptional repressor Tbx3 is required for the hormone-sensing cell lineage in mammary epithelium.

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    Kamini Kunasegaran

    Full Text Available The transcriptional repressor Tbx3 is involved in lineage specification in several tissues during embryonic development. Germ-line mutations in the Tbx3 gene give rise to Ulnar-Mammary Syndrome (comprising reduced breast development and Tbx3 is required for mammary epithelial cell identity in the embryo. Notably Tbx3 has been implicated in breast cancer, which develops in adult mammary epithelium, but the role of Tbx3 in distinct cell types of the adult mammary gland has not yet been characterized. Using a fluorescent reporter knock-in mouse, we show that in adult virgin mice Tbx3 is highly expressed in luminal cells that express hormone receptors, and not in luminal cells of the alveolar lineage (cells primed for milk production. Flow cytometry identified Tbx3 expression already in progenitor cells of the hormone-sensing lineage and co-immunofluorescence confirmed a strict correlation between estrogen receptor (ER and Tbx3 expression in situ. Using in vivo reconstitution assays we demonstrate that Tbx3 is functionally relevant for this lineage because knockdown of Tbx3 in primary mammary epithelial cells prevented the formation of ER+ cells, but not luminal ER- or basal cells. Interestingly, genes that are repressed by Tbx3 in other cell types, such as E-cadherin, are not repressed in hormone-sensing cells, highlighting that transcriptional targets of Tbx3 are cell type specific. In summary, we provide the first analysis of Tbx3 expression in the adult mammary gland at a single cell level and show that Tbx3 is important for the generation of hormone-sensing cells.

  16. Research resource: nuclear receptor atlas of human retinal pigment epithelial cells: potential relevance to age-related macular degeneration.

    Science.gov (United States)

    Dwyer, Mary A; Kazmin, Dmitri; Hu, Peng; McDonnell, Donald P; Malek, Goldis

    2011-02-01

    Retinal pigment epithelial (RPE) cells play a vital role in retinal physiology by forming the outer blood-retina barrier and supporting photoreceptor function. Retinopathies including age-related macular degeneration (AMD) involve physiological and pathological changes in the epithelium, severely impairing the retina and effecting vision. Nuclear receptors (NRs), including peroxisome proliferator-activated receptor and liver X receptor, have been identified as key regulators of physiological pathways such as lipid metabolic dysregulation and inflammation, pathways that may also be involved in development of AMD. However, the expression levels of NRs in RPE cells have yet to be systematically surveyed. Furthermore, cell culture lines are widely used to study the biology of RPE cells, without knowledge of the differences or similarities in NR expression and activity between these in vitro models and in vivo RPE. Using quantitative real-time PCR, we assessed the expression patterns of all 48 members of the NR family plus aryl hydrocarbon receptor and aryl hydrocarbon receptor nuclear translocator in human RPE cells. We profiled freshly isolated cells from donor eyes (in vivo), a spontaneously arising human cell line (in vitro), and primary cell culture lines (in vitro) to determine the extent to which NR expression in the cultured cell lines reflects that of in vivo. To evaluate the validity of using cell culture models for investigating NR receptor biology, we determined transcriptional activity and target gene expression of several moderately and highly expressed NRs in vitro. Finally, we identified a subset of NRs that may play an important role in pathobiology of AMD.

  17. Seasonal cell proliferation in the chemosensory epithelium and brain of red-backed salamanders, Plethodon cinereus.

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    Dawley, E M; Fingerlin, A; Hwang, D; John, S S; Stankiewicz, C A

    2000-06-01

    The chemosensory epithelium of vertebrates retains the ability to produce new receptor neurons throughout life, presumably as a mechanism to replace aging or damaged receptors. We examined cell division in the main olfactory and vomeronasal epithelia of red-backed salamanders (Plethodon cinereus) because previous studies had shown that the volume of sensory epithelia changes seasonally. Cell division was compared throughout the year by injecting salamanders once with 5-bromo-2'-deoxyuridine (BrdU), which is incorporated into the DNA of cells during DNA synthesis, and sacrificing them one hour after injection. We used immunocytochemistry to locate cells that had arisen from cell division since BrdU injection and compared the number of labeled cells per area among animals. Animals collected in May had significantly more labeled nuclei than animals collected in any other month. However, proliferation rates among the other months were not significantly different and were quite low. Labeled nuclei also were found around the cerebral ventricles of salamanders collected in May, but rarely in any other month, although other tissues in the head often were heavily labeled. Cell proliferation appears to be up-regulated in the chemosensory epithelia and in the telencephalon during May, and we hypothesize that new receptors, and perhaps their interneurons in the telencephalon, are being generated in anticipation of seasonal events that are mediated by chemoreception. Copyright 2000 S. Karger AG, Basel

  18. Tannic acid binding of cell surfaces in normal, premalignant, and malignant squamous epithelium of the human uterine cervix.

    Science.gov (United States)

    Davina, J H; Lamers, G E; van Haelst, U J; Kenemans, P; Stadhouders, A M

    1984-01-01

    Alterations in tannic acid (TA) binding capacity of cell surface carbohydrates in normal, premalignant, and malignant squamous epithelium of the human uterine cervix have been studied using electron microscopic visualization in combination with microdensitometric evaluation. While in normal epithelium there is distinct binding in four to five cell layers of the deep intermediate zone, cells of carcinoma in situ and invasive cancer lesions lack TA binding. In moderate dysplasia an intermediate reacting pattern is found. Deep intermediate cells in areas bordering the carcinoma in situ lesions do not show any binding, although their ultrastructure cannot be distinguished from similar cells in normal tissue. The TA deposition within the deep intermediate zone is probably related to the presence here of glycoprotein-containing membrane-coating granules. The finding that TA binding discriminates between cells in normal squamous epithelium and morphologically normal cells in juxtaposition with lesional areas in premalignant and malignant epithelium opens the possibility for a more reliable cytologic diagnosis of cervical epithelial neoplasia.

  19. Chronic cigarette smoke causes oxidative damage and apoptosis to retinal pigmented epithelial cells in mice.

    Directory of Open Access Journals (Sweden)

    Masashi Fujihara

    Full Text Available The purpose of this study was to determine whether mice exposed to chronic cigarette smoke develop features of early age-related macular degeneration (AMD. Two month old C57Bl6 mice were exposed to either filtered air or cigarette smoke in a smoking chamber for 5 h/day, 5 days/week for 6 months. Eyes were fixed in 2.5% glutaraldehyde/2% paraformaldehyde and examined for ultrastructural changes by transmission electron microscopy. The contralateral eye was fixed in 2% paraformaldehyde and examined for oxidative injury to the retinal pigmented epithelium (RPE by 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-OHdG immunolabeling and apoptosis by TUNEL labeling. Mice exposed to cigarette smoke had immunolabeling for 8-OHdG in 85+/-3.7% of RPE cells counted compared to 9.5+/-3.9% in controls (p<0.00001. Bruch membrane was thicker in mice exposed to smoke (1086+/-332 nm than those raised in air (543+/-132 nm; p = 0.0069. The two most pronounced ultrastructural changes (severity grading scale from 0-3 seen were a loss of basal infoldings (mean difference in grade = 1.98; p<0.0001, and an increase in intracellular vacuoles (mean difference in grade = 1.7; p<0.0001. Ultrastructural changes to Bruch membrane in cigarette-smoke exposed mice were smaller in magnitude but consistently demonstrated significantly higher grade injury in cigarette-exposed mice, including basal laminar deposits (mean difference in grade = 0.54; p<0.0001, increased outer collagenous layer deposits (mean difference in grade = 0.59; p = 0.002, and increased basal laminar deposit continuity (mean difference in grade = 0.4; p<0.0001. TUNEL assay showed a higher percentage of apoptotic RPE from mice exposed to cigarette smoke (average 8.0+/-1.1% than room air (average 0+/-0%; p = 0.043. Mice exposed to chronic cigarette smoke develop evidence of oxidative damage with ultrastructural degeneration to the RPE and Bruch membrane, and RPE cell apoptosis. This model could be useful for studying the

  20. The Id2+ distal tip lung epithelium contains individual multipotent embryonic progenitor cells.

    Science.gov (United States)

    Rawlins, Emma L; Clark, Cheryl P; Xue, Yan; Hogan, Brigid L M

    2009-11-01

    The conducting airways (bronchi and bronchioles) and peripheral gas exchange (alveolar) regions of the mammalian lung are generated by a process of branching morphogenesis. Evidence suggests that during embryonic development, the undifferentiated epithelial progenitors are located at the distal tips of the branching epithelium. To test this hypothesis, we used an Id2-CreER(T2) knock-in mouse strain to lineage trace the distal epithelial tip cells during either the pseudoglandular or canalicular phases of development. During the pseudoglandular stage, the tip cells both self-renew and contribute descendents to all epithelial cell lineages, including neuroendocrine cells. In addition, individual Id2(+) tip cells can self-renew and contribute descendents to both the bronchiolar and alveolar compartments. By contrast, during the later canalicular stage, the distal epithelial tip cells only contribute descendents to the alveoli. Taken together, this evidence supports a model in which the distal tip of the developing lung contains a multipotent epithelial population, the fate of which changes during development.

  1. Expression of vitamin D receptor and cathelicidin in human corneal epithelium cells during fusarium solani infection.

    Science.gov (United States)

    Cong, Lin; Xia, Yi-Ping; Zhao, Gui-Qiu; Lin, Jing; Xu, Qiang; Hu, Li-Ting; Qu, Jian-Qiu; Peng, Xu-Dong

    2015-01-01

    To observe the expression of vitamin D receptor (VDR) in human specimen and immortalized human corneal epithelium cells (HCEC) when challenged with fusarium solani. Moreover, we decided to discover the pathway of VDR expression. Also, we would like to detect the expression of cathelicidin antimicrobial peptide (CAMP) in the downstream pathway of VDR. Immunohistochemistry was used to examine the VDR expression in HCEC from healthy and fungal keratitis patients. Real time quantitative polymerase chain reaction (qPCR) was performed to observe the messenger ribonucleic acid (mRNA) change of VDR when immortalized HCEC were challenged with fusarium solani for different hours. CAMP was detected at both mRNA and protein levels. We found out that the VDR expression in fusarium solani keratitis patients' specimen was much more than that in healthy people. The mRNA and protein expression of VDR increased when we stimulated HCEC with fusarium solani antigen (Pfusarium solani antigen stimulation (Pfusarium solani antigen.

  2. Aquaporin-1 Expression in Retinal Pigment Epithelial Cells Overlying Retinal Drusen

    DEFF Research Database (Denmark)

    Tran, Thuy Linh; Bek, Toke; la Cour, Morten

    2016-01-01

    PURPOSE: In the outer retina, age-related macular degeneration (AMD) results in reduced hydraulic conductivity in Bruch's membrane, possibly leading to altered water transport in retinal pigment epithelial (RPE) cells. We hypothesize that RPE cells may express aquaporin-1 (AQP1) to compensate...

  3. RNA interference inhibits expression of vascular endothelial growth factor (VEGF) in human retinal pigment epithelial cells

    Institute of Scientific and Technical Information of China (English)

    CAI Chun-mei; SUN Bao-chen; LIU Xu-yang; WANG Jin-jin; LI Jun-fa; HAN Song; WANG Ning-li; LU Qing-jun

    2005-01-01

    @@ Choroidal neovascularization (CNV), a major cause of vision loss, is the result of the increased vascular endothelial growth factor (VEGF) expression in human retinal pigment epithelial (RPE) cells. It is important to inhibit the expression of VEGF protein in RPE cells.

  4. Snail involves in the transforming growth factor β1-mediated epithelial-mesenchymal transition of retinal pigment epithelial cells.

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    Hui Li

    Full Text Available BACKGROUND: The proliferation of retinal pigment epithelium (RPE cells resulting from an epithelial-mesenchymal transition (EMT plays a key role in proliferative vitreoretinopathy (PVR, which leads to complex retinal detachment and the loss of vision. Genes of Snail family encode the zinc finger transcription factors that have been reported to be essential in EMT during embryonic development and cancer metastasis. However, the function of Snail in RPE cells undergoing EMT is largely unknown. PRINCIPAL FINDINGS: Transforming growth factor beta(TGF-β-1 resulted in EMT in human RPE cells (ARPE-19, which was characterized by the expected decrease in E-cadherin and Zona occludin-1(ZO-1 expression, and the increase in fibronectin and α-smooth muscle actin (α-SMA expression, as well as the associated increase of Snail expression at both mRNA and protein levels. Furthermore, TGF-β1 treatment caused a significant change in ARPE-19 cells morphology, with transition from a typical epithelial morphology to mesenchymal spindle-shaped. More interestingly, Snail silencing significantly attenuated TGF-β1-induced EMT in ARPE-19 cells by decreasing the mesenchymal markers fibronectin and a-SMA and increasing the epithelial marker E-cadherin and ZO-1. Snail knockdown could effectively suppress ARPE-19 cell migration. Finally, Snail was activated in epiretinal membranes from PVR patients. Taken together, Snail plays very important roles in TGF-β-1-induced EMT in human RPE cells and may contribute to the development of PVR. SIGNIFICANCE: Snail transcription factor plays a critical role in TGF-β1-induced EMT in human RPE cells, which provides deep insight into the pathogenesis of human PVR disease. The specific inhibition of Snail may provide a new approach to treat and prevent PVR.

  5. Sensory cell proliferation within the olfactory epithelium of developing adult Manduca sexta (Lepidoptera.

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    Marie-Dominique Franco

    Full Text Available BACKGROUND: Insects detect a multitude of odors using a broad array of phenotypically distinct olfactory organs referred to as olfactory sensilla. Each sensillum contains one to several sensory neurons and at least three support cells; these cells arise from mitotic activities from one or a small group of defined precursor cells. Sensilla phenotypes are defined by distinct morphologies, and specificities to specific odors; these are the consequence of developmental programs expressed by associated neurons and support cells, and by selection and expression of subpopulations of olfactory genes encoding such proteins as odor receptors, odorant binding proteins, and odor degrading enzymes. METHODOLOGY/PRINCIPAL FINDINGS: We are investigating development of the olfactory epithelium of adult M. sexta, identifying events which might establish sensilla phenotypes. In the present study, antennal tissue was examined during the first three days of an 18 day development, a period when sensory mitotic activity was previously reported to occur. Each antenna develops as a cylinder with an outward facing sensory epithelium divided into approximately 80 repeat units or annuli. Mitotic proliferation of sensory cells initiated about 20-24 hrs after pupation (a.p., in pre-existing zones of high density cells lining the proximal and distal borders of each annulus. These high density zones were observed as early as two hr. a.p., and expanded with mitotic activity to fill the mid-annular regions by about 72 hrs a.p. Mitotic activity initiated at a low rate, increasing dramatically after 40-48 hrs a.p.; this activity was enhanced by ecdysteroids, but did not occur in animals entering pupal diapause (which is also ecdysteroid sensitive. CONCLUSIONS/SIGNIFICANCE: Sensory proliferation initiates in narrow zones along the proximal and distal borders of each annulus; these zones rapidly expand to fill the mid-annular regions. These zones exist prior to any mitotic activity

  6. Inductive differentiation of conjunctival goblet cells by γ-secretase inhibitor and construction of recombinant conjunctival epithelium.

    Science.gov (United States)

    Tian, Le; Qu, Mingli; Wang, Yao; Duan, Haoyun; Di, Guohu; Xie, Lixin; Zhou, Qingjun

    2014-06-01

    γ-secretase inhibitor has been shown to promote intestinal goblet cell differentiation. We now demonstrated that the in vitro addition of γ-secretase inhibitor in the culture of human conjunctival epithelial cells significantly promoted the differentiation of conjunctival goblet cells with typical droplet-like phenotype, positive periodic acid-Schiff and goblet cell-specific Muc5Ac, cytokeratin 7 and Helix pomatia agglutinin lectin staining. Moreover, topical application of γ-secretase inhibitor promoted the differentiation of mouse conjunctival goblet cells in vivo. Furthermore, the expression of Notch target gene HES-1 was down-regulated during the differentiation of conjunctival goblet cells. In addition, we found that the recombinant conjunctival epithelium on amniotic membrane showed less goblet cell density and abnormal location when compared with normal conjunctival epithelium, which were improved by the addition of γ-secretase inhibitor in the final induction. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Drosophila DOCK Family Protein Zizimin Involves in Pigment Cell Differentiation in Pupal Retinae.

    Science.gov (United States)

    Ozasa, Fumito; Morishita, Kazushige; Dang, Ngoc Anh Suong; Miyata, Seiji; Yoshida, Hideki; Yamaguchi, Masamitsu

    2017-08-26

    The dedicator of cytokinesis (DOCK) family proteins are known as one of guanine nucleotide exchange factors (GEFs), that contribute to cellular signaling processes by activating small G proteins. Although mammalian Zizimin is known to be a GEF for Cdc42 of Rho family small GTPase, its role in vivo is not well understood. Here we studied in vivo function of Drosophila Zizimin (Ziz). Knockdown of Ziz in eye imaginal discs induced the rough eye phenotype accompanied with fusion of ommatidia, loss of bristles and loss of pigments. Immunostaining analyses revealed that Ziz mainly localizes in the secondary pigment cells (SPCs) and tertiary pigment cells (TPCs) in pupal retinae. Ziz-knockdown induced SPC- and TPC-like cells with aberrant morphology in the pupal retina. Delta (Dl), a downstream target of EGFR signaling is known to regulate pigment cell differentiation. Loss-of-function mutation of Dl suppressed the rough eye phenotype and the defect in differentiation of SPCs and TPCs in Ziz-knockdown flies. Moreover, Ziz-knockdown increased Dl expression level especially in SPCs and TPCs. In addition, mutations of rhomboid-1 and roughoid that are activators of EGFR signaling pathway also suppressed both the rough eye phenotype and the defect in differentiation of SPCs and TPCs in Ziz-knockdown flies. Activation of EGFR signaling in Ziz-knockdown flies were further confirmed by immunostaining with anti-diphospho ERK IgG. These results indicate that Ziz negatively regulates the Dl expression in SPCs and TPCs to control differentiation of pigment cells and this regulation is mediated by EGFR signaling pathway.Key words: Zizimin, DOCK, EGFR signaling pathway, pigment cell, Drosophila.

  8. Cistos primários do epitélio pigmentar da íris e corpo ciliar: aspectos de biomicroscopia ultra-sônica Primary cysts of the iris and ciliary body pigment epithelium: ultrasound biomicroscopy features

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    Bernadete Ayres

    2000-10-01

    Full Text Available Objetivo: Descrever as características, incidência e distribuição dos cistos primários de epitélio pigmentar de íris e corpo ciliar ao exame de biomicroscopia ultra-sônica, que devem ser diferenciados de lesões sólidas. Métodos: Foram estudados de modo retrospectivo os prontuários de 73 pacientes, 82 olhos, com diagnóstico ecográfico de cisto primário de íris ou corpo ciliar durante o período de janeiro/97 a dezembro/99. Utilizou-se o biomicroscópio ultra-sônico, aplicando técnicas padronizadas de imersão. Resultados: À biomicroscopia ultra-sônica os cistos caracterizaram-se por apresentarem paredes finas e regulares, e conteúdo anecóico. Quarenta e oito pacientes (65,7% eram do sexo feminino. A maior incidência (28,8% ocorreu para o grupo incluído no intervalo de 20 a 29 anos de idade. Observou-se uma característica distribuição, predominantemente nos quadrantes temporais inferiores. Conclusões: A biomicroscopia ultra-sônica mostrou-se útil no diagnóstico de cistos primários do epitélio pigmentar da íris e do corpo ciliar, auxiliando na diferenciação de patologias tumorais e avaliando possíveis complicações. O conhecimento dos critérios ecográficos e da distribuição epidemiológica facilitam o diagnóstico destas lesões.Purpose: To describe the ultrasound biomicroscopic characteristics, incidence, distribution and location of primary cysts of the iris and ciliary body pigment epithelium, and to differentiate them from solid lesions. Methods: A retrospective study was performed through a review of charts of 73 patients, 82 eyes, with echographic diagnosis of primary cysts of the iris and ciliary body pigment epithelium during a 36-month period (January/97 through December/99. All examinations were performed using an ultrasound biomicroscope applying standard immersion techniques. Results: Ultrasound biomicroscopy revealed typical findings of the primary cysts of the pigment epithelium such as thin

  9. Review of spectral domain-enhanced depth imaging optical coherence tomography of tumors of the retina and retinal pigment epithelium in children and adults

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    Carol L Shields

    2015-01-01

    Full Text Available Background: Spectral domain (SD enhanced depth imaging optical coherence tomography (EDI-OCT is a useful tool for anatomic, cross-sectional imaging of retinal conditions. Aims: The aim was to identify characteristic patterns of retinal and retinal pigment epithelial tumors on EDI-OCT in children and adults. Settings and Design: Retrospective review. Materials and Methods: Analysis of published reports and personal observations using office-based EDI-OCT for adults and portable hand-held SD OCT for infants and children. Results: Using EDI-OCT, retinal tumors such as small retinoblastoma, astrocytic hamartoma, and hemangioblastoma arose abruptly from the retina, immediately adjacent to normal retina. Small exophytic retinoblastoma and retinal hemangioblastoma showed the full-thickness, homogeneous retinal disorganization with surrounding normal retina "draping" over the margins. Retinoblastoma occasionally had intralesional cavities and surrounding subretinal fluid. Hemangioblastoma often had adjacent intraretinal edema and subretinal fluid. Astrocytic hamartoma arose within the nerve fiber layer and sometimes with a "moth-eaten" or cavitary appearance. Retinal pigment epithelial (RPE lesions such as congenital hypertrophy of RPE appeared flat with shadowing, occasional subretinal cleft, and abrupt photoreceptor loss. Congenital simple hamartoma showed an abrupt elevation from the inner retina with crisp, dark posterior shadowing. Combined hamartoma of the retina/RPE showed vitreoretinal traction causing "sawtooth mini-peak" or gently "maxi-peak" folding of the retina. RPE adenoma often produces remote macular edema or epiretinal membrane and the tumor has an irregular, "rugged" surface with deep shadowing. Conclusions: Enhanced depth imaging optical coherence tomography shows characteristic patterns that are suggestive of certain retinal and RPE tumors.

  10. The differentiated airway epithelium infected by influenza viruses maintains the barrier function despite a dramatic loss of ciliated cells.

    Science.gov (United States)

    Wu, Nai-Huei; Yang, Wei; Beineke, Andreas; Dijkman, Ronald; Matrosovich, Mikhail; Baumgärtner, Wolfgang; Thiel, Volker; Valentin-Weigand, Peter; Meng, Fandan; Herrler, Georg

    2016-12-22

    Virus-host interactions in the respiratory epithelium during long term influenza virus infection are not well characterized. Therefore, we developed an air-liquid interface culture system for differentiated porcine respiratory epithelial cells to study the effect of virus-induced cellular damage. In our well-differentiated cells, α2,6-linked sialic acid is predominantly expressed on the apical surface and the basal cells mainly express α2,3-linked sialic acid. During the whole infection period, release of infectious virus was maintained at a high titre for more than seven days. The infected epithelial cells were subject to apoptosis resulting in the loss of ciliated cells together with a thinner thickness. Nevertheless, the airway epithelium maintained trans-epithelial electrical resistance and retained its barrier function. The loss of ciliated cells was compensated by the cells which contained the KRT5 basal cell marker but were not yet differentiated into ciliated cells. These specialized cells showed an increase of α2,3-linked sialic acid on the apical surface. In sum, our results help to explain the localized infection of the airway epithelium by influenza viruses. The impairment of mucociliary clearance in the epithelial cells provides an explanation why prior viral infection renders the host more susceptible to secondary co-infection by another pathogen.

  11. Ultrastructural characteristic of cells and pigment analysis in floating and submerged leaves of Trapa natans L.

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    Оlena M. Nedukha

    2012-03-01

    Full Text Available The comparative analysis of ultrastructure of the photosynthetic cells and pigment content of Trapa natans in both floating and submerged leaves at vegetative phase were conducted. It has shown that the changes of cell ultrasructure and pigment content in leaves are depended from the location of leaves above or under water surface. It has ascertained that submersion of the leaves under water lead to: 1 increase of thylakoid number in grana; 2 decrease of number of the chloroplasts with starch grains; 3 decrease of the relation between chlorophylls (Chlа/ Chlb and of the sum of chlorophylls (Chlа+ Chlb in comparison with analogical parameters in floating leaves

  12. Non-invasive exploration of neonatal gastric epithelium by using exfoliated epithelial cells.

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    Bertrand Kaeffer

    Full Text Available BACKGROUND & AIMS: In preterm infants, exfoliated gastric epithelial cells can be retrieved from aspirates sampled through the naso-gastric feeding tube. Our aims were to determine (1 whether the recovery of exfoliated cells is feasible at any time from birth through the removal of the nasogastric tube, (2 whether they can be grown in culture in vitro, and (3 whether the physiological state of exfoliated cells expressing H+/K+ -ATPases reflects that of their counterparts remaining in situ at the surface of the gastric epithelium in neonatal rat pups. METHODS: In infants, gastric fluid aspirates were collected weekly after birth or every 3 hours over 24-h periods, and related to clinical parameters (Biocollection PROG/09/18. In rat pups submitted to a single fasting/refeeding cycle, we explored circadian exfoliation with the cellular counter-parts in the gland. All samples were analyzed by confocal imaging and Enzyme-Linked Immunosorbent Assay. RESULTS: Epithelial cells were identified by microscopy using membrane-bound anti-H+/K+ ATPases antibody, assessed for nucleus integrity, and the expression of selected proteins (autophagy, circadian clock. On 34 infants, the H+/K+-ATPase-positive cells were consistently found quiescent, regardless of gestational age and feeding schedule from day-5 of life to the day of removal of the naso-gastric tube. By logistic regression analysis, we did find a positive correlation between the intensity of exfoliation (cellular loss per sample and the postnatal age (p<0.001. The H+/K+ ATPase-positive cells established in culture retained the expression of a biomarker of progenitor status (Pouf5F1-Oct4. In rat pups, the expression pattern of Survivin in H+/K+ ATPase-positive exfoliated cells paralleled that observed in cells remaining at the surface of the gastric gland. CONCLUSIONS: Tracking parietal cells can improve clinical monitoring and understanding of the autophagic death via the phosphatidylinositol 3-kinase

  13. Use of Mesothelial Cells and Biological Matrices for Tissue Engineering of Simple Epithelium Surrogates

    Science.gov (United States)

    Lachaud, Christian Claude; Rodriguez-Campins, Berta; Hmadcha, Abdelkrim; Soria, Bernat

    2015-01-01

    Tissue-engineering technologies have progressed rapidly through last decades resulting in the manufacture of quite complex bioartificial tissues with potential use for human organ and tissue regeneration. The manufacture of avascular monolayered tissues such as simple squamous epithelia was initiated a few decades ago and is attracting increasing interest. Their relative morphostructural simplicity makes of their biomimetization a goal, which is currently accessible. The mesothelium is a simple squamous epithelium in nature and is the monolayered tissue lining the walls of large celomic cavities (peritoneal, pericardial, and pleural) and internal organs housed inside. Interestingly, mesothelial cells can be harvested in clinically relevant numbers from several anatomical sources and not less important, they also display high transdifferentiation capacities and are low immunogenic characteristics, which endow these cells with therapeutic interest. Their combination with a suitable scaffold (biocompatible, degradable, and non-immunogenic) may allow the manufacture of tailored serosal membranes biomimetics with potential spanning a wide range of therapeutic applications, principally for the regeneration of simple squamous-like epithelia such as the visceral and parietal mesothelium vascular endothelium and corneal endothelium among others. Herein, we review recent research progresses in mesothelial cells biology and their clinical sources. We make a particular emphasis on reviewing the different types of biological scaffolds suitable for the manufacture of serosal mesothelial membranes biomimetics. Finally, we also review progresses made in mesothelial cells-based therapeutic applications and propose some possible future directions. PMID:26347862

  14. The potential of chitosan in enhancing peptide and protein absorption across the TR146 cell culture model-an in vitro model of the buccal epithelium

    DEFF Research Database (Denmark)

    Portero, Ana; Remuñán-López, Carmen; Nielsen, Hanne Mørck

    2002-01-01

    To investigate the potential of chitosan (CS) to enhance buccal peptide and protein absorption, the TR146 cell culture model, a model of the buccal epithelium, was used.......To investigate the potential of chitosan (CS) to enhance buccal peptide and protein absorption, the TR146 cell culture model, a model of the buccal epithelium, was used....

  15. Current smoking-specific gene expression signature in normal bronchial epithelium is enhanced in squamous cell lung cancer

    NARCIS (Netherlands)

    Boelens, Mirjam C.; van den Berg, Anke; Fehrmann, Rudolf S. N.; Geerlings, Marie; de Jong, Wouter K.; te Meerman, Gerard J; Sietsma, Hannie; Timens, Winn; Postma, Dirkje S.; Groen, Harry J. M.

    2009-01-01

    Cigarette smoking is the main risk factor for the development of squamous cell lung carcinoma (SCC). However, the smoking-related molecular changes in SCC have not been studied. Gene expression studies in both histologically normal bronchial epithelium and SCC epithelial samples identified genes dif

  16. Impact of lactic Acid bacteria on dendritic cells from allergic patients in an experimental model of intestinal epithelium.

    Science.gov (United States)

    Ratajczak, Céline; Duez, Catherine; Grangette, Corinne; Pochard, Pierre; Tonnel, André-Bernard; Pestel, Joël

    2007-01-01

    Lactic acid bacteria (LAB) are Gram positive nonpathogenic commensal organisms present in human gastrointestinal tract. In vivo, LAB are separated from antigen-presenting cells such as dendritic cells (DC) by the intestinal epithelial barrier. In this study, the impact of one LAB strain (Lactobacillus casei ATCC393) on human monocyte-derived DC from allergic and healthy donors was assessed by using a polarized epithelium model. Confocal and flow cytometer analyses showed that immature DC efficiently captured FITC-labelled L. casei through the epithelial layer. After interaction with L. casei, DC acquired a partial maturation status (i.e., CD86 and CD54 increase) and increased their interleukin (IL)-10 and IL-12 production. Interestingly, after activation by L. casei in the presence of experimental epithelium, DC from allergic patients instructed autologous naïve CD4(+) T cells to produce more interferon-gamma than without the epithelium. Thus by modulating human DC reactivity, LAB and intestinal epithelium might modify T cell immune response and regulate the development of allergic reaction.

  17. Impact of Lactic Acid Bacteria on Dendritic Cells from Allergic Patients in an Experimental Model of Intestinal Epithelium

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    Céline Ratajczak

    2007-01-01

    Full Text Available Lactic acid bacteria (LAB are Gram positive nonpathogenic commensal organisms present in human gastrointestinal tract. In vivo, LAB are separated from antigen-presenting cells such as dendritic cells (DC by the intestinal epithelial barrier. In this study, the impact of one LAB strain (Lactobacillus casei ATCC393 on human monocyte-derived DC from allergic and healthy donors was assessed by using a polarized epithelium model. Confocal and flow cytometer analyses showed that immature DC efficiently captured FITC-labelled L. casei through the epithelial layer. After interaction with L. casei, DC acquired a partial maturation status (i.e., CD86 and CD54 increase and increased their interleukin (IL-10 and IL-12 production. Interestingly, after activation by L. casei in the presence of experimental epithelium, DC from allergic patients instructed autologous naïve CD4+ T cells to produce more interferon-γ than without the epithelium. Thus by modulating human DC reactivity, LAB and intestinal epithelium might modify T cell immune response and regulate the development of allergic reaction.

  18. The migration and loss of human primordial germ stem cells from the hind gut epithelium towards the gonadal ridge

    DEFF Research Database (Denmark)

    Mamsen, Linn Salto; Brøchner, Christian Beltoft; Byskov, Anne Grete

    2012-01-01

    Human primordial germ cells (PGCs) can be recognized in the yolk sac wall, from 3-4 weeks post conception (wpc), in the hind gut epithelium from week 4 and in the gonadal area from early week 5. The objective of this study was to map the migration route of PGCs and elucidate the role of the nervous...

  19. Immunolocalization of osteopontin in dysplasias and squamous cell carcinomas arising from oral epithelium

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    Thara Aravind

    2017-01-01

    Conclusion: The expression of OPN in full thickness of epithelium in severe dysplasias, carcinoma in situ, and in the superficial epithelium of OSCC suggest the possibility of considering OPN expression in full epithelial thickness in dysplasias as an indicator for malignant transformation.

  20. Evidence of progenitor cells of glandular and myoepithelial cell lineages in the human adult female breast epithelium: a new progenitor (adult stem) cell concept.

    Science.gov (United States)

    Boecker, Werner; Buerger, Horst

    2003-10-01

    Although experimental data clearly confirm the existence of self-renewing mammary stem cells, the characteristics of such progenitor cells have never been satisfactorily defined. Using a double immunofluorescence technique for simultaneous detection of the basal cytokeratin 5, the glandular cytokeratins 8/18 and the myoepithelial differentiation marker smooth muscle actin (SMA), we were able to demonstrate the presence of CK5+ cells in human adult breast epithelium. These cells have the potential to differentiate to either glandular (CK8/18+) or myoepithelial cells (SMA+) through intermediary cells (CK5+ and CK8/18+ or SMA+). We therefore proceeded on the assumption that the CK5+ cells are phenotypically and behaviourally progenitor (committed adult stem) cells of human breast epithelium. Furthermore, we furnish evidence that most of these progenitor cells are located in the luminal epithelium of the ductal lobular tree. Based on data obtained in extensive analyses of proliferative breast disease lesions, we have come to regard usual ductal hyperplasia as a progenitor cell-derived lesion, whereas most breast cancers seem to evolve from differentiated glandular cells. Double immunofluorescence experiments provide a new tool to characterize phenotypically progenitor (adult stem) cells and their progenies. This model has been shown to be of great value for a better understanding not only of normal tissue regeneration but also of proliferative breast disease. Furthermore, this model provides a new tool for unravelling further the regulatory mechanisms that govern normal and pathological cell growth.

  1. Activation of influenza viruses by proteases from host cells and bacteria in the human airway epithelium.

    Science.gov (United States)

    Böttcher-Friebertshäuser, Eva; Klenk, Hans-Dieter; Garten, Wolfgang

    2013-11-01

    Influenza is an acute infection of the respiratory tract, which affects each year millions of people. Influenza virus infection is initiated by the surface glycoprotein hemagglutinin (HA) through receptor binding and fusion of viral and endosomal membranes. HA is synthesized as a precursor protein and requires cleavage by host cell proteases to gain its fusion capacity. Although cleavage of HA is crucial for virus infectivity, little was known about relevant proteases in the human airways for a long time. Recent progress in the identification and characterization of HA-activating host cell proteases has been considerable however and supports the idea of targeting HA cleavage as a novel approach for influenza treatment. Interestingly, certain bacteria have been demonstrated to support HA activation either by secreting proteases that cleave HA or due to activation of cellular proteases and thereby may contribute to virus spread and enhanced pathogenicity. In this review, we give an overview on activation of influenza viruses by proteases from host cells and bacteria with the main focus on recent progress on HA cleavage by proteases HAT and TMPRSS2 in the human airway epithelium. In addition, we outline investigations of HA-activating proteases as potential drug targets for influenza treatment. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  2. Cellular effects of tributyltin (TBT) on the penis epithelium cells of prosobranchs ( Hinia reticulata and Ocinebrina aciculata)

    Science.gov (United States)

    Brick, M.; Deutsch, U.; Fioroni, P.

    1996-09-01

    Cytopathological effects on organelles of penis epithelium cells were investigated in prosobranchs that had been exposed for two weeks to three months to high TBT-concentrations in artificial seawater. TBT exposure damaged cell organelles, such as mitochondria, Golgi dictyosomes, endoplasmatic reticulum, and injured the cell membranes. In addition, atypical intercellular spaces were observed between the cells of the epithelial layer. Further cell alterations included the increase of residual bodies within the cells as well as structural changes of the basal lamina. The ultrastructural changes were compared with cell alterations of specimens which had been collected in a polluted environment on the coast of Brittany (France).

  3. Epigenetic silencing of MAL, a putative tumor suppressor gene, can contribute to human epithelium cell carcinoma

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    Zhang Jun

    2010-11-01

    Full Text Available Abstract Background To identify new and useful candidate biomarkers in head and neck squamous cell carcinoma (HNSCC, we performed a genome-wide survey and found that Myelin and lymphocyte-associated protein (MAL was a gene that was markedly down-regulated in HNSCC. Hence, we investigated the mechanism of MAL silencing and the effects of MAL on the proliferation, invasion, and apoptotic potential in HNSCC. Results MAL was significantly down-regulated in 91.7% of HNSCC specimens at the mRNA level as compared with adjacent normal tissues (P = 0.0004. Moreover, the relative transcript levels of the MAL gene were remarkably decreased by five-fold in nine HNSCC cell lines as compared with normal head and neck epithelium cells. MAL gene expression was restored in 44%, 67%, and 89% in HNSCC cell lines treated with TSA, 5-Aza-dC, and TSA plus 5-Aza-dC, respectively. Furthermore, bisulfate-treated DNA sequencing demonstrated that the two CpG islands (that is, M1 and M2 located in MAL promoter region were completely methylated in the HNSCC cell lines (CpG methylated ratio was more than 90%, and only one CpG island (that is, M1 was partially methylated in HNSCC tissues (CpG methylated ratio between 20% and 90%. A significant reduction in cell proliferation and a change in the cell cycle profile were also observed in MAL transfectants. Matrigel assay demonstrated that the invasiveness of HNSCC cells significantly decreased. A significant increase in the population of apoptotic cells was observed in MAL transfected cells. The exogenous expression of the MAL gene suppressed malignant phenotypes, while the cell death induced by MAL gene transfer was a result of apoptosis as demonstrated by the induction of cleavage of the poly (that is, ADP-ribose polymerase. Additionally, tumor growth was suppressed in cells expressing MAL as compared with cells not expressing MAL. Conclusion Our data suggest that the epigenetic inactivation of MAL, as a candidate tumor

  4. Sox5 functions as a fate switch in medaka pigment cell development.

    Directory of Open Access Journals (Sweden)

    Yusuke Nagao

    2014-04-01

    Full Text Available Mechanisms generating diverse cell types from multipotent progenitors are crucial for normal development. Neural crest cells (NCCs are multipotent stem cells that give rise to numerous cell-types, including pigment cells. Medaka has four types of NCC-derived pigment cells (xanthophores, leucophores, melanophores and iridophores, making medaka pigment cell development an excellent model for studying the mechanisms controlling specification of distinct cell types from a multipotent progenitor. Medaka many leucophores-3 (ml-3 mutant embryos exhibit a unique phenotype characterized by excessive formation of leucophores and absence of xanthophores. We show that ml-3 encodes sox5, which is expressed in premigratory NCCs and differentiating xanthophores. Cell transplantation studies reveal a cell-autonomous role of sox5 in the xanthophore lineage. pax7a is expressed in NCCs and required for both xanthophore and leucophore lineages; we demonstrate that Sox5 functions downstream of Pax7a. We propose a model in which multipotent NCCs first give rise to pax7a-positive partially fate-restricted intermediate progenitors for xanthophores and leucophores; some of these progenitors then express sox5, and as a result of Sox5 action develop into xanthophores. Our results provide the first demonstration that Sox5 can function as a molecular switch driving specification of a specific cell-fate (xanthophore from a partially-restricted, but still multipotent, progenitor (the shared xanthophore-leucophore progenitor.

  5. Insect Pupil Mechanisms. I. On the Pigment Migration in the Retinula Cells of Hymenoptera (Suborder Apocrita)

    NARCIS (Netherlands)

    Stavenga, D.G.; Kuiper, J.W.

    1977-01-01

    The pupil mechanism of Hymenoptera (suborder Apocrita) has been studied by simultaneous recordings of transmission and reflection from the compound eye of virtually intact animals. It is confirmed that the light flux in the photoreceptors is controlled by pigment granules in the retinula cells; the

  6. ASIP and TYR pigmentation variants associate with cutaneous melanoma and basal cell carcinoma.

    NARCIS (Netherlands)

    Gudbjartsson, D.F.; Sulem, P.; Stacey, S.N.; Goldstein, A.M.; Rafnar, T.; Sigurgeirsson, B.; Benediktsdottir, K.R.; Thorisdottir, K.; Ragnarsson, R.; Sveinsdottir, S.G.; Magnusson, V.; Lindblom, A.; Kostulas, K.; Botella-Estrada, R.; Soriano, V.; Juberias, P.; Grasa, M.; Saez, B.; Andres, R.; Scherer, D.; Rudnai, P.; Gurzau, E.; Koppova, K.; Kiemeney, L.A.L.M.; Jakobsdottir, M.; Steinberg, S.; Helgason, A.; Gretarsdottir, S.; Tucker, M.A.; Mayordomo, J.I.; Nagore, E.; Kumar, R.; Hansson, J.; Olafsson, J.H.; Gulcher, J.; Kong, A.; Thorsteinsdottir, U.; Stefansson, K.

    2008-01-01

    Fair color increases risk of cutaneous melanoma (CM) and basal cell carcinoma (BCC). Recent genome-wide association studies have identified variants affecting hair, eye and skin pigmentation in Europeans. Here, we assess the effect of these variants on risk of CM and BCC in European populations

  7. Migrating mast cells in the gallbladder epithelium of cattle and sheep. A comparative morphologic and histochemical study.

    Science.gov (United States)

    Toledo, O M; Morales, C R; Pereyra, L A; Jordão, T; Montes, G S

    1981-01-01

    This paper reports the existence of mast cells in an epithelial location in the gallbladders of both cattle and sheep. The histochemical studies performed on these cells showed that their cytoplasmic granules contain heparin and biogenic amines in both species. Optical- and electron microscopic observations demonstrated that, in both species, mast cells from the connective tissue of the gallbladder diapedese across the basal lamina and migrate through the epithelium all the way to the luminal surface, and that a degranulation process takes place during this migration. The biochemical results showed a correlation between the number of mast cells present in the epithelium and the amount of heparin detected in the different regions of the gallbladders of the species studied. Unusually high contents of heparin were found in both cattle and sheep gallbladders, suggesting that they should be studied as possible commercial sources of this polimer.

  8. The protection of salidroside on oxidative stress induced in human lens epithelium cells

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    Li-Ting Liu

    2017-10-01

    Full Text Available AIM: To explore the effect of different concentrations of salidroside on H2O2 induced oxidative stress damage in human lens epithelium cells(HLEC. METHODS: HLEC were cultured and divided into negative control group: cultured in normal cultivation; oxidative damage group: treated with 100μmol/L H2O2 for 12h; Salidroside low concentration group: 10μmol/L salidroside treated for 24h and H2O2 treated for 12h; Salidroside high concentration group: 100μmol/L salidroside treated for 24h and H2O2 treated for 12h. MTT method was applied to observe the effect of salidroside on HLEC survival rate. Morphological change of each group were observed and recorded under inverted microscope. DCFH-DA fluorescent probe was applied to detect intracellular ROS changes; content of malondialdehyde(MDA, superoxide dismutase(SODand glutathione peroxidase(GSH-Pxin supernatants were detected by pectrophotometer. RESULTS: Salidroside obviously inhibited H2O2-induced HLEC vitality decline, inhibited ROS generation in cells, causing SOD, GSH-Px levels increased and MDA levels decreased. CONCLUSION: Salidroside inhibited H2O2 induced HLEC injury by decreasing the intracellular MDA content levels and increasing SOD, GSH-Px content levels, which conclude that salidroside may have a certain role in the treatment of HLEC damage.

  9. Synthesis of solar cells sensitized using natural photosynthetic pigments & study for the cell performance under different synthesis parameters

    Science.gov (United States)

    Roa, Simon; Radhakrishnan, Sivakumar; Manidurai, Paulraj

    2016-05-01

    In this study we used photosynthetic pigments extracted from spinach and purple cabbage for their potential application in dye sensitized solar cells (DSSC). Pigments were extracted by dissolving small amounts of each one of these plant products in methanol and distilled water. The extraction was also done at two different temperatures (70° C and 80° C respectively). This was to assess for the solvent that promotes better extraction of the pigments. A parallel study was also carried out using a mixture of both these dyes in 1:1 ratio. Good absorption, about 60% to 80% was obtained for spinach pigments diluted in methanol in the visible range between 400-480nm, and between 9% to 15% for purple cabbage pigments in the wavelength range between 480-630 nm when extracted using distilled water at 80°C. In contrast, the diluted mixture in methanol shows good absorption of 20% and 32% for wavelengths in the range 400-480nm. Solar cells sensitized using these natural dyes were studied for their photovoltaic properties by measuring current-voltage behavior. Efficiencies ranging from 0.011% to 0.0719% were observed. Mixture of spinach & purple cabbage pigments extracted using methanol was found to have the highest efficiency of 0.0719%.

  10. New Advanced Technologies in Stem Cell Therapy

    Science.gov (United States)

    2014-11-01

    bacterial products, viruses, growth factors, and oxidative stress, the complex is activated. Activated IKKβ phosphorylates IkB, leading to its...eye may prove more straightforward targets for cell ther- apy. Loss of the retinal pigment epithelium (RPE) in age-related macular degeneration has...Buchholz et al., Rapid and efficient directed differentiation of human pluripotent stem cells into retinal pigmented epithelium. Stem Cells Transl. Med. 2

  11. Tongue Epithelium Cells from shRNA Mediated Transgenic Goat Show High Resistance to Foot and Mouth Disease Virus.

    Science.gov (United States)

    Li, Wenting; Wang, Kejun; Kang, Shimeng; Deng, Shoulong; Han, Hongbing; Lian, Ling; Lian, Zhengxing

    2015-12-16

    Foot and mouth disease induced by foot and mouth disease virus (FMDV) is severe threat to cloven-hoofed domestic animals. The gene 3Dpol in FMDV genome encodes the viral RNA polymerase, a vital element for FMDV replication. In this study, a conserved 3D-7414shRNA targeting FMDV-3Dpol gene was designed and injected into pronuclear embryos to produce the transgenic goats. Sixty-one goats were produced, of which, seven goats positively integrated 3D-7414shRNA. Loss of function assay demonstrated that siRNA effectively knockdown 3Dpol gene in skin epithelium cells of transgenic goats. Subsequently, the tongue epithelium cells from transgenic and non-transgenic goats were infected with FMDV O/YS/CHA/05 strain. A significant decrease of virus titres and virus copy number was observed in cells of transgenic goats compared with that of non-transgenic goats, which indicated that 3D-7414siRNA inhibited FMDV replication by interfering FMDV-3Dpol gene. Furthermore, we found that expression of TLR7, RIG-I and TRAF6 was lower in FMDV infected cells from transgenic goats compared to that from non-transgenic goats, which might result from lower virus copy number in transgenic goats' cells. In conclusion, we successfully produced transgenic goats highly expressing 3D-7414siRNA targeting 3Dpol gene, and the tongue epithelium cells from the transgenic goats showed effective resistance to FMDV.

  12. Dermatoscopy-guided therapy of pigmented basal cell carcinoma with imiquimod*

    Science.gov (United States)

    Husein-ElAhmed, Husein; Fernandez-Pugnaire, Maria Antonia

    2016-01-01

    BACKGROUND Dermatoscopy is a non-invasive diagnostic tool used to examine skin lesions with an optical magnification. It has been suggested as a useful tool for monitoring therapeutic response in lentigo maligna patients treated with imiquimod. OBJECTIVE To examine the accuracy of dermatoscopy as a tool to monitor the therapeutic response of pigmented basal cell carcinoma treated with imiquimod. METHOD The authors designed a prospective study. Patients with pigmented basal cell carcinoma were included and data regarding the dermatoscopy features were collected following the Menzies criteria, prior to initiating the imiquimod treatment. Subsequent dermatoscopic evaluations were performed at weeks 4 and 8, following imiquimod discontinuation. RESULTS Twenty lesions were included. The most common pigmented dermatoscopy features were large blue-grey ovoid nests (80%), followed by blue-grey globules (50%) and leaf-like areas (30%). No spoke wheel areas were observed. In 17 out of 20 patients, a response was noted during the first evaluation at 4 weeks, while the clearance was noted at the second check-up after 8 weeks. In two patients, the clearance was found at the initial evaluation at 4 weeks, while in one patient, the response remained unchanged. Blue-grey globules were the fastest to exhibit clearance (50% at week 4), followed by leaf-like areas (15%) and large blue-grey ovoid nests (6.25%). CONCLUSION According to our results, dermatoscopic evaluation enhances the accuracy in the assessment of the clinical response to imiquimod in pigmented basal cell carcinoma. PMID:28099598

  13. SMAD4 regulates cell motility through transcription of N-cadherin in human pancreatic ductal epithelium.

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    Ya'an Kang

    Full Text Available Expression of the cellular adhesion protein N-cadherin is a critical event during epithelial-mesenchymal transition (EMT. The SMAD4 protein has been identified as a mediator of transforming growth factor-β (TGF-β superfamily signaling, which regulates EMT, but the mechanisms linking TGF-β signaling to N-cadherin expression remain unclear. When the TGF-β pathway is activated, SMAD proteins, including the common mediator SMAD4, are subsequently translocated into the nucleus, where they influence gene transcription via SMAD binding elements (SBEs. Here we describe a mechanism for control of CDH2, the gene encoding N-cadherin, through the canonical TGFβ-SMAD4 pathway. We first identified four previously undescribed SBEs within the CDH2 promoter. Using telomerase immortalized human pancreatic ductal epithelium, we found that TGF-β stimulation prompted specific SMAD4 binding to all four SBEs. Luciferase reporter and SMAD4-knockdown experiments demonstrated that specific SMAD4 binding to the SBE located at -3790 bp to -3795 bp within the promoter region of CDH2 was necessary for TGF-β-stimulated transcription. Expression of N-cadherin on the surface of epithelial cells facilitates motility and invasion, and we demonstrated that knockdown of SMAD4 causes decreased N-cadherin expression, which results in diminished migration and invasion of human pancreatic ductal epithelial cells. Similar reduction of cell motility was produced after CDH2 knockdown. Together, these findings suggest that SMAD4 is critical for the TGF-β-driven upregulation of N-cadherin and the resultant invasive phenotype of human pancreatic ductal epithelial cells during EMT.

  14. Pigmented epidermal cyst with dense collection of melanin: A rare entity - Report of a case with review of the literature.

    Science.gov (United States)

    Jayalakshmy, P S; Subitha, K; Priya, P V; Johnson, Gerald

    2012-05-01

    Epidermal cyst is a very common benign cystic lesion of the skin. It is usual to find ulceration of the lining epithelium, rupture of the cyst wall with chronic inflammation and foreign body giant cell reaction. But, it is very rare to see an epidermal cyst with marked accumulation of melanin pigment. Only a few cases of pigmented epidermal cyst with dense collection of melanin pigment have been published in the literature. Here, we are reporting a case of ruptured epidermal cyst with keratin granuloma formation and showing dense collection of melanin pigment.

  15. Ovarian Surface Epithelium in Patients with Severe Ovarian Infertility: A Potential Source of Cells Expressing Markers of Pluripotent/Multipotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Irma Virant-Klun

    2011-01-01

    Full Text Available The aim of this study was to confirm the presence of stem cells in the ovarian surface epithelium of patients with premature ovarian failure and no mature follicles and oocytes. In these patients, small round cells of unknown origin expressing SOX-2 marker of pluripotency were observed among the epithelial cells just after the ovarian surface epithelium scraping. These cells were an integral part of the ovarian surface epithelium. When the scraped cells were cultured in a medium with added follicular fluid to provide some ovarian niche, primitive oocyte-like cells and typical round-shaped cell clusters positively stained on alkaline phosphatase, and markers of pluripotency, such as SOX-2 and SSEA-4, were developed. These markers were expressed early and also later in the culture. Single oocyte-like cells expressed genes OCT4A, SOX-2, NANOG, NANOS, STELLA, CD9, LIN28, KLF4, GDF3, and MYC, characteristic for pluripotent stem cells. The results of this study confirmed the presence of putative stem cells in the ovarian surface epithelium of these patients and provided some basis to create a stem cell line in the future.

  16. Cell proliferation and growth-associated protein 43 expression in the olfactory epithelium in Poecilia reticulata after copper solution exposure

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    S Bettini

    2009-06-01

    Full Text Available This study investigated the regeneration in the olfactory mucosa of the teleostean fish Poecilia reticulata when returned to dechlorinated tap water after 4-day exposure to 30 ?g/L of Cu2+. The regeneration process in the olfactory tissue was examined in fishes at 0, 3, 6 and 10 days of recovery in well water. Jade B staining permitted to evaluate the rate of the damage which was especially extended to olfactory neurons. Immediately after the end of exposure, a massive mitotic activity in the basal region of the mucosa was detected by immunostaining with PCNA. After 3 days of recovery the nuclei of the newly formed cells had already finished their migration to the upper portion of the epithelium, and cellular division was much less intense. Simultaneously, immunoreactivity for the neural growth-associated phosphoprotein GAP-43 increased respect to control levels, revealing that the new differentiating PCNA-positive elements belonged to immature neurons. After 6 days in well water no mitotic activity was detected, while the GAP-43 labelling appeared particularly concentrated in the apical surface of the olfactory epithelium.After 10 days the aspect of the olfactory epithelium was almost identical to the control. The present results suggest that after 10 days regeneration seems to be complete and integrity of the tissue restored. Furthermore, the epithelium reconstitution does not show apparent divergence from other fishes or mammals.

  17. A confocal microscopic study of solitary pulmonary neuroendocrine cells in human airway epithelium

    Directory of Open Access Journals (Sweden)

    Sparrow Malcolm P

    2005-10-01

    Full Text Available Abstract Background Pulmonary neuroendocrine cells (PNEC are specialized epithelial cells that are thought to play important roles in lung development and airway function. PNEC occur either singly or in clusters called neuroepithelial bodies. Our aim was to characterize the three dimensional morphology of PNEC, their distribution, and their relationship to the epithelial nerves in whole mounts of adult human bronchi using confocal microscopy. Methods Bronchi were resected from non-diseased portions of a lobe of human lung obtained from 8 thoracotomy patients (Table 1 undergoing surgery for the removal of lung tumors. Whole mounts were stained with antibodies to reveal all nerves (PGP 9.5, sensory nerves (calcitonin gene related peptide, CGRP, and PNEC (PGP 9.5, CGRP and gastrin releasing peptide, GRP. The analysis and rendition of the resulting three-dimensional data sets, including side-projections, was performed using NIH-Image software. Images were colorized and super-imposed using Adobe Photoshop. Results PNEC were abundant but not homogenously distributed within the epithelium, with densities ranging from 65/mm2 to denser patches of 250/mm2, depending on the individual wholemount. Rotation of 3-D images revealed a complex morphology; flask-like with the cell body near the basement membrane and a thick stem extending to the lumen. Long processes issued laterally from its base, some lumenal and others with feet-like processes. Calcitonin gene-related peptide (CGRP was present in about 20% of PNEC, mainly in the processes. CGRP-positive nerves were sparse, with some associated with the apical part of the PNEC. Conclusion Our 3D-data demonstrates that PNEC are numerous and exhibit a heterogeneous peptide content suggesting an active and diverse PNEC population.

  18. Functional and Molecular Characterization of Rod-like Cells from Retinal Stem Cells Derived from the Adult Ciliary Epithelium

    Science.gov (United States)

    Demontis, Gian Carlo; Aruta, Claudia; Comitato, Antonella; De Marzo, Anna; Marigo, Valeria

    2012-01-01

    In vitro generation of photoreceptors from stem cells is of great interest for the development of regenerative medicine approaches for patients affected by retinal degeneration and for high throughput drug screens for these diseases. In this study, we show unprecedented high percentages of rod-fated cells from retinal stem cells of the adult ciliary epithelium. Molecular characterization of rod-like cells demonstrates that they lose ciliary epithelial characteristics but acquire photoreceptor features. Rod maturation was evaluated at two levels: gene expression and electrophysiological functionality. Here we present a strong correlation between phototransduction protein expression and functionality of the cells in vitro. We demonstrate that in vitro generated rod-like cells express cGMP-gated channels that are gated by endogenous cGMP. We also identified voltage-gated channels necessary for rod maturation and viability. This level of analysis for the first time provides evidence that adult retinal stem cells can generate highly homogeneous rod-fated cells. PMID:22432014

  19. Functional and molecular characterization of rod-like cells from retinal stem cells derived from the adult ciliary epithelium.

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    Gian Carlo Demontis

    Full Text Available In vitro generation of photoreceptors from stem cells is of great interest for the development of regenerative medicine approaches for patients affected by retinal degeneration and for high throughput drug screens for these diseases. In this study, we show unprecedented high percentages of rod-fated cells from retinal stem cells of the adult ciliary epithelium. Molecular characterization of rod-like cells demonstrates that they lose ciliary epithelial characteristics but acquire photoreceptor features. Rod maturation was evaluated at two levels: gene expression and electrophysiological functionality. Here we present a strong correlation between phototransduction protein expression and functionality of the cells in vitro. We demonstrate that in vitro generated rod-like cells express cGMP-gated channels that are gated by endogenous cGMP. We also identified voltage-gated channels necessary for rod maturation and viability. This level of analysis for the first time provides evidence that adult retinal stem cells can generate highly homogeneous rod-fated cells.

  20. Induction of necrotic cell death by oxidative stress in retinal pigment epithelial cells.

    Science.gov (United States)

    Hanus, J; Zhang, H; Wang, Z; Liu, Q; Zhou, Q; Wang, S

    2013-12-12

    Age-related macular degeneration (AMD) is a degenerative disease of the retina and the leading cause of blindness in the elderly. Retinal pigment epithelial (RPE) cell death and the resultant photoreceptor apoptosis are characteristic of late-stage dry AMD, especially geographic atrophy (GA). Although oxidative stress and inflammation have been associated with GA, the nature and underlying mechanism for RPE cell death remains controversial, which hinders the development of targeted therapy for dry AMD. The purpose of this study is to systematically dissect the mechanism of RPE cell death induced by oxidative stress. Our results show that characteristic features of apoptosis, including DNA fragmentation, caspase 3 activation, chromatin condensation and apoptotic body formation, were not observed during RPE cell death induced by either hydrogen peroxide or tert-Butyl hydroperoxide. Instead, this kind of cell death can be prevented by RIP kinase inhibitors necrostatins but not caspase inhibitor z-VAD, suggesting necrotic feature of RPE cell death. Moreover, ATP depletion, receptor interacting protein kinase 3 (RIPK3) aggregation, nuclear and plasma membrane leakage and breakdown, which are the cardinal features of necrosis, were observed in RPE cells upon oxidative stress. Silencing of RIPK3, a key protein in necrosis, largely prevented oxidative stress-induced RPE death. The necrotic nature of RPE death is consistent with the release of nuclear protein high mobility group protein B1 into the cytoplasm and cell medium, which induces the expression of inflammatory gene TNFα in healthy RPE and THP-1 cells. Interestingly, features of pyroptosis or autophagy were not observed in oxidative stress-treated RPE cells. Our results unequivocally show that necrosis, but not apoptosis, is a major type of cell death in RPE cells in response to oxidative stress. This suggests that preventing oxidative stress-induced necrotic RPE death may be a viable approach for late-stage dry

  1. 色素上皮衍生因子抑制人肝癌裸鼠移植瘤生长%Pigment epithelium-derived factor gene therapy inhibits the growth of transplanted human hepatocellular carcinoma in nude mice

    Institute of Scientific and Technical Information of China (English)

    高云; 张伟; 赵亮; 王学浩

    2009-01-01

    目的 观察人色素上皮衍生因子(PEDF)对血管生成的抑制作用,探讨PEDF在肝癌基因治疗中的应用前景. 方法构建色素上皮衍生因子慢病毒表达质粒pLenti-PEDF,经293T细胞包装,收集病毒上清液,感染肝癌细胞株HepG2.收集各组细胞的条件培养基,通过Westernblot分析各组细胞PEDF的表达情况,并通过人脐静脉血管内皮细胞增殖及迁移试验研究其体外生物学活性.人肝癌细胞HepG2移植到裸鼠皮下,研究Lenti-PEDF病毒对肝癌移植瘤生长的抑制作用,逆转录聚合酶链反应检测肿瘤组织中PEDF mRNA表达.多组间均数比较采用单因素方差分析,组间两两比较采用LSD法.结果 限制性内切酶酶切分析和测序结果均表明成功构建了PEDF慢病毒表达载体,以293T细胞包装的重组慢病毒能够高效感染肝癌细胞,肝痛细胞感染重组慢病毒后可高效表达PEDF并分泌到培养上清液中.体外研究结果表明,重组PEDF可明显抑制人脐静脉血管内皮细胞的增殖及迁移,抑制率分别达29%和48%,与空白对照组相比,差异有统计学意义(P值均<0.01).Lenti-PEDF病毒能明显抑制人肝癌裸鼠皮下移植瘤的生长(P<0.01).瘤内注射Lenti-PEDF病毒21 d后,逆转录聚合酶链反应在肿瘤组织检测到PEDF mRNA的过表达.结论 本研究初步提示PEDF能有效遏制肿瘤的血管生成和肿瘤生长,为肝癌的基因治疗提供了一条新的思路.%Objectives To evaluate the antiangiogenic property of pigment epithelium-derived factor (PEDF) in heptocarcinoma cell lines and explore its possible application in the gene therapy of human hepa-tocellular carcinoma (HCC). Methods The gene encoding human PEDF was subcloned into lentiviral vector to generate the recombinant plasmid pLenti-PEDF. The plasmid pLenti-PEDF and two other packag-ing plasmids were cotransfected to 293T cells by calcium phosphate. Then HepG2 was infected with recom-binant lentivirus and the expression

  2. Expression of endothelin receptors in frog, chicken, mouse and human pigment cells.

    Science.gov (United States)

    Scarparo, Ana Cristina; Isoldi, Mauro César; de Lima, Leonardo Henrique Ribeiro Graciani; Visconti, Maria Aparecida; Castrucci, Ana Maria de Lauro

    2007-07-01

    Several reports have shown the participation of vasoactive endothelins (ETs) in the regulation of vertebrate pigment cells. In the present study, we identified ET receptors in pigment cells of vertebrate species by RT-PCR assays, and compared the differential expression of the various subtypes in each species by quantitative PCR. RT-PCR was performed with specific primers for ETC, ETA(X) or ETA in Xenopus laevis melanophores, ETA or ETB(2) in chicken melanocytes, ETA or ETB in murine (B-16, S-91 or Melan-A) or human (SK-Mel 23 or SK-Mel 28) melanoma cells, and the products obtained were confirmed by cloning and sequencing. The results showed the presence of ETA(X), but not ETA mRNA, and confirmed the expression of ETC in X. laevis melanophores. ETA and ETB(2) mRNAs were also demonstrated in chicken melanocytes. ETA and ETB receptor were identified in S-91, B16 and Melan-A murine cells. In human melanoma cells, SK-Mel 23 and SK-Mel 28, we confirmed the presence of ETB mRNA, and also found ETA mRNA. The comparison between the two subtypes present in the pigment cell of each species and among species demonstrated that the expression of ETAs in chicken, mouse, and human melanocytes is negligible, as is the expression of ETA(X) in Xenopus melanophores. The relative expression, as determined by quantitative PCR, was as follows: chicken ETB>SK-Mel 23 ETB>S91 ETB>Xenopus ETC, suggesting that the endothelin system plays a major role in avian and mammalian pigment cell regulation, as compared to lower vertebrates. The phylogenetic analysis revealed that subtype A receptors were probably the most primitive ET receptors, directly deriving from the ancestral type; all the other receptors, B subtypes and C, originated from diverse derivative molecules.

  3. Evolution of pigment cell regression in the cavefish Astyanax: a late step in melanogenesis.

    Science.gov (United States)

    McCauley, David W; Hixon, Ernest; Jeffery, William R

    2004-01-01

    Pigmentation and eyes are often lost in cave-adapted animals. Although the mechanisms of eye degeneration are beginning to be understood, little is known about the evolutionary and developmental processes involved in pigment cell regression. In teleost embryos, a population of neural crest cells migrates into the body wall and differentiates into melanophores, xanthophores, and iridophores. All three pigment cell types are present in the eyed surface-dwelling form (surface fish) of the teleost Astyanax mexicanus. However, melanophores are absent or substantially reduced in number in various derived populations of the conspecific blind cave-dwelling form (cavefish). We show here that tyrosinase-positive melanoblasts are present in cavefish. DiI labeling revealed a population of trunk neural crest cells in cavefish embryos that migrate to locations normally occupied by differentiated melanophores. We also discovered a cell population in cavefish embryos and adults resembling melanoblasts in several features, including the ability to synthesize melanin when supplied with the tyrosinase substrate l-dopa. DiI-tyrosinase double-labeling and neural keel explant experiments showed that the tyrosinase-positive cells are derived from the neural crest. The number of melanoblasts varies in different adult cavefish populations relative to the extent of melanophore reduction. Although cavefish melanoblasts can synthesize melanin from exogenous l-dopa, they are unable to convert exogenous l-tyrosine to l-dopa and melanin. We conclude that pigment cell regression in cavefish is mediated by an evolutionary change late in melanogenesis that may involve an impediment in the ability to convert l-tyrosine to l-dopa and melanin.

  4. Lipid droplets, perilipins and cytokeratins--unravelled liaisons in epithelium-derived cells.

    Directory of Open Access Journals (Sweden)

    Hans Heid

    Full Text Available Lipid droplets (LDs are spherical accumulations of apolar lipids and other hydrophobic substances and are generally surrounded by a thin cortical layer of specific amphiphilic proteins (APs. These APs segregate the LDs from the mostly polar components of the cytoplasm. We have studied LDs in epithelium-derived cell cultures and in particular characterized proteins from the perilipin (PLIN gene family - in mammals consisting of the proteins Perilipin, Adipophilin, TIP47, S3-12 and MLDP/OXPAT (PLIN 1-5. Using a large number of newly generated and highly specific mono- and polyclonal antibodies specific for individual APs, and using improved LD isolation methods, we have enriched and characterized APs in greater detail and purity. The majority of lipid-AP complexes could be obtained in the top layer fractions of density gradient centrifugation separations of cultured cells, but APs could also be detected in other fractions within such separations. The differently sized LD complexes were analyzed using various biochemical methods and mass spectrometry as well as immunofluorescence and electron- in particular immunoelectron-microscopy. Moreover, by immunoprecipitation, protein-protein binding assays and by immunoelectron microscopy we identified a direct linkage between LD-binding proteins and the intermediate-sized filaments (IF cytokeratins 8 and 18 (also designated as keratins K8 and K18. Specifically, in gradient fractions of higher density supposedly containing small LDs, we received as co-precipitations cytidylyl-, palmitoyl- and cholesterol transferases and other specific enzymes involved in lipid metabolism. So far, common proteomic studies have used LDs from top layer fractions only and did not report on these transferases and other enzymes. In addition to findings of short alternating hydrophobic/hydrophilic segments within the PLIN protein family, we propose and discuss a model for the interaction of LD-coating APs with IF proteins.

  5. Lipid droplets, perilipins and cytokeratins--unravelled liaisons in epithelium-derived cells.

    Science.gov (United States)

    Heid, Hans; Rickelt, Steffen; Zimbelmann, Ralf; Winter, Stefanie; Schumacher, Heiderose; Dörflinger, Yvette

    2013-01-01

    Lipid droplets (LDs) are spherical accumulations of apolar lipids and other hydrophobic substances and are generally surrounded by a thin cortical layer of specific amphiphilic proteins (APs). These APs segregate the LDs from the mostly polar components of the cytoplasm. We have studied LDs in epithelium-derived cell cultures and in particular characterized proteins from the perilipin (PLIN) gene family - in mammals consisting of the proteins Perilipin, Adipophilin, TIP47, S3-12 and MLDP/OXPAT (PLIN 1-5). Using a large number of newly generated and highly specific mono- and polyclonal antibodies specific for individual APs, and using improved LD isolation methods, we have enriched and characterized APs in greater detail and purity. The majority of lipid-AP complexes could be obtained in the top layer fractions of density gradient centrifugation separations of cultured cells, but APs could also be detected in other fractions within such separations. The differently sized LD complexes were analyzed using various biochemical methods and mass spectrometry as well as immunofluorescence and electron- in particular immunoelectron-microscopy. Moreover, by immunoprecipitation, protein-protein binding assays and by immunoelectron microscopy we identified a direct linkage between LD-binding proteins and the intermediate-sized filaments (IF) cytokeratins 8 and 18 (also designated as keratins K8 and K18). Specifically, in gradient fractions of higher density supposedly containing small LDs, we received as co-precipitations cytidylyl-, palmitoyl- and cholesterol transferases and other specific enzymes involved in lipid metabolism. So far, common proteomic studies have used LDs from top layer fractions only and did not report on these transferases and other enzymes. In addition to findings of short alternating hydrophobic/hydrophilic segments within the PLIN protein family, we propose and discuss a model for the interaction of LD-coating APs with IF proteins.

  6. Multiple pigment cell types contribute to the black, blue, and orange ornaments of male guppies (Poecilia reticulata.

    Directory of Open Access Journals (Sweden)

    Verena A Kottler

    Full Text Available The fitness of male guppies (Poecilia reticulata highly depends on the size and number of their black, blue, and orange ornaments. Recently, progress has been made regarding the genetic mechanisms underlying male guppy pigment pattern formation, but we still know little about the pigment cell organization within these ornaments. Here, we investigate the pigment cell distribution within the black, blue, and orange trunk spots and selected fin color patterns of guppy males from three genetically divergent strains using transmission electron microscopy. We identified three types of pigment cells and found that at least two of these contribute to each color trait. Further, two pigment cell layers, one in the dermis and the other in the hypodermis, contribute to each trunk spot. The pigment cell organization within the black and orange trunk spots was similar between strains. The presence of iridophores in each of the investigated color traits is consistent with a key role for this pigment cell type in guppy color pattern formation.

  7. COMBINED EFFECT OF ELECTROMAGNETIC RADIATION, DNA-INTERCALATORS, C60-FULLERENE AND CAFFEINE ON HUMAN BUCCAL EPITHELIUM CELLS

    OpenAIRE

    G. B. Skamrova; Prylutskyy, Yu I.; M. P. Evstigneev

    2014-01-01

    Now the number of physical and chemical biologically active damage factors dramatically increased. The ways to neutralize such effects have not been studied enough. In this work the techniques of visual assessment of chromatin granulation and of electronegativity of human buccal epithelium cell nuclei were used in order to study the combined effects of the exposure to low-intensity electromagnetic radiation of the millimeter range electromagnetic radiation and to the DNA-binding compounds, su...

  8. Retinal pigment epithelial cells upregulate expression of complement factors after co-culture with activated T cells

    DEFF Research Database (Denmark)

    Juel, Helene Bæk; Kaestel, Charlotte; Folkersen, Lasse

    2011-01-01

    In this study we examined the effect of T cell-derived cytokines on retinal pigment epithelial (RPE) cells with respect to expression of complement components. We used an in vitro co-culture system in which CD3/CD28-activated human T cells were separated from the human RPE cell line (ARPE-19) by ...... of inflammatory ocular diseases such as uveitis and age-related macular degeneration. --------------------------------------------------------------------------------...

  9. Calcium-independent phospholipase A2 regulates retinal pigment epithelium proliferation and may be important in the pathogenesis of retinal diseases

    DEFF Research Database (Denmark)

    Kolko, M; Kiilgaard, J F; Wang, J

    2009-01-01

    the expression of iPLA2-VIA in proliferative vitreoretinopathy (PVR). PVR membranes revealed nuclear expression of iPLA2-VIA in the RPE cells which had migrated and participated in the formation of the membranes. Overall, the present results point to an important role of iPLA2-VIA in the regulation of RPE...

  10. Exploiting the Autofluorescent Properties of Photosynthetic Pigments for Analysis of Pigmentation and Morphology in Live Fremyella diplosiphon Cells

    Directory of Open Access Journals (Sweden)

    Juliana R. Bordowitz

    2010-07-01

    Full Text Available Fremyella diplosiphon is a freshwater, filamentous cyanobacterium that exhibits light-dependent regulation of photosynthetic pigment accumulation and cellular and filament morphologies in a well-known process known as complementary chromatic adaptation (CCA. One of the techniques used to investigate the molecular bases of distinct aspects of CCA is confocal laser scanning microscopy (CLSM. CLSM capitalizes on the autofluorescent properties of cyanobacterial phycobiliproteins and chlorophyll a. We employed CLSM to perform spectral scanning analyses of F. diplosiphon strains grown under distinct light conditions. We report optimized utilization of CLSM to elucidate the molecular basis of the photoregulation of pigment accumulation and morphological responses in F. diplosiphon.

  11. Inhibition of Corneal Neovascularization with the Combination of Bevacizumab and Plasmid Pigment Epithelium-Derived Factor-Synthetic Amphiphile INTeraction-18 (p-PEDF-SAINT-18 Vector in a Rat Corneal Experimental Angiogenesis Model

    Directory of Open Access Journals (Sweden)

    Ching-Hsein Chen

    2013-04-01

    Full Text Available Bevacizumab, a 149-kDa protein, is a recombinant humanized monoclonal antibody to VEGF. PEDF, a 50-kDa glycoprotein, has demonstrated anti-vasopermeability properties. In this study, we demonstrated that the combination of bevacizumab and plasmid pigment epithelium-derived factor-synthetic amphiphile INTeraction-18 (p-PEDF-SAINT-18 has a favorable antiangiogenic effect on corneal NV. Four groups (Group A: 0 μg + 0 μg, B: 0.1 μg + 0.1 μg, C: 1 μg + 1 μg, and D: 10 μg + 10 μg of bevacizumab + p-PEDF-SAINT-18 were prepared and implanted into the rat subconjunctival substantia propria 1.5 mm from the limbus on the temporal side. Then, 1 μg of p-bFGF-SAINT-18 was prepared and implanted into the rat corneal stroma 1.5 mm from the limbus on the same side. The inhibition of NV was observed and quantified from days 1 to 60. Biomicroscopic examination, western blot analysis and immunohistochemistry were used to analyze the 18-kDa bFGF, 50-kDa PEDF and VEGF protein expression. No inhibition activity for normal limbal vessels was noted. Subconjunctival injection with the combination of bevacizumab and p-PEDF-SAINT-18 successfully inhibited corneal NV. The bFGF and PEDF genes were successfully expressed as shown by western blot analysis, and a mild immune response to HLA-DR was shown by immunohistochemistry. We concluded that the combination of bevacizumab and p-PEDF-SAINT-18 may have more potent and prolonged antiangiogenic effects, making it possible to reduce the frequency of subconjunctival.Bevacizumab, a 149-kDa protein, is a recombinant humanized monoclonalantibody to VEGF. PEDF, a 50-kDa glycoprotein, has demonstrated anti-vasopermeabilityproperties. In this study, we demonstrated that the combination of bevacizumaband plasmid pigment epithelium-derived factor-synthetic amphiphile INTeraction-18(p-PEDF-SAINT-18 has a favorable antiangiogenic effect on corneal NV. Four groups(Group A: 0 μg + 0 μg, B: 0.1 μg + 0.1 μg, C: 1 μg + 1 μg, and

  12. 间充质干细胞向上皮细胞的诱导分化及应用研究进展%Differentiation of mesenchymal stem cell into epithelium and application

    Institute of Scientific and Technical Information of China (English)

    臧传宝; 李栋

    2011-01-01

    Mesenchymal stem cells (MSC) is able to differentiate into a variety of epithelial cells,such as alveolar epithelium,tubular epithelium and corneal epithelial cells in vivo and in vitro under the given condition.After transfusion,MSC can effectively repair the injured lung epithelial cells,and relieve inflammation.MSC can also repair the renal tubular cell damage by reducing renal interstitial infiltration of inflammatory cells,promoting regeneration of renal tubular epithelial cells and inhibiting of apoptosis; Biological cornea can be available constructed by using MSC,which can availably repair the injured ocular surface.In the other hands,MSC can express keratinocyte growth factors and other cytokines,promoting limbal stem cell proliferation.In addition,MSC can also differentiate into pancreatic ductal epithelial cells,endometrial epithelial cells,spermatogenic epithelium and human retinal pigment epithelium.MSC has great application potential in epithelial diseases,and provide a good and effective choice in treatment of some epithelial diseases.%间充质干细胞( mesenchymal stem cell,MSC)在体内外可被诱导分化为多种上皮细胞,如肺泡上皮、肾小管上皮和角膜上皮细胞等,表达上皮细胞特异性标志.MSC回输体内后,可有效修复损伤的肺上皮细胞组织,缓解炎症损伤,减轻肾小管细胞损伤、减少肾间质炎症细胞浸润,促进肾小管上皮细胞再生,并抑制细胞凋亡;也可在载体上利用MSC构建生物角膜,进行眼表修复,MSC本身还能表达角化生长因子等多种因子促进角膜缘干细胞增殖.另外,MSC还可以向胰腺导管上皮细胞、子宫内膜上皮细胞、生精上皮细胞、人视网膜色素上皮细胞等分化.MSC在临床治疗上皮细胞损伤类疾病中展现出其巨大的应用潜能,为上皮类疾病的治疗提供了新的方法.

  13. Efflux protein expression in human stem cell-derived retinal pigment epithelial cells.

    Directory of Open Access Journals (Sweden)

    Kati Juuti-Uusitalo

    Full Text Available Retinal pigment epithelial (RPE cells in the back of the eye nourish photoreceptor cells and form a selective barrier that influences drug transport from the blood to the photoreceptor cells. At the molecular level, ATP-dependent efflux transporters have a major role in drug delivery in human RPE. In this study, we assessed the relative expression of several ATP-dependent efflux transporter genes (MRP1, -2, -3, -4, -5, -6, p-gp, and BCRP, the protein expression and localization of MRP1, MRP4, and MRP5, and the functionality of MRP1 efflux pumps at different maturation stages of undifferentiated human embryonic stem cells (hESC and RPE derived from the hESC (hESC-RPE. Our findings revealed that the gene expression of ATP-dependent efflux transporters MRP1, -3, -4, -5, and p-gp fluctuated during hESC-RPE maturation from undifferentiated hESC to fusiform, epithelioid, and finally to cobblestone hESC-RPE. Epithelioid hESC-RPE had the highest expression of MRP1, -3, -4, and P-gp, whereas the most mature cobblestone hESC-RPE had the highest expression of MRP5 and MRP6. These findings indicate that a similar efflux protein profile is shared between hESC-RPE and the human RPE cell line, ARPE-19, and suggest that hESC-RPE cells are suitable in vitro RPE models for drug transport studies. Embryonic stem cell model might provide a novel tool to study retinal cell differentiation, mechanisms of RPE-derived diseases, drug testing and targeted drug therapy.

  14. Identification of short hairpin RNA targeting foot-and-mouth disease virus with transgenic bovine fetal epithelium cells.

    Directory of Open Access Journals (Sweden)

    Hongmei Wang

    Full Text Available BACKGROUND: Although it is known that RNA interference (RNAi targeting viral genes protects experimental animals, such as mice, from the challenge of Foot-and-mouth disease virus (FMDV, it has not been previously investigated whether shRNAs targeting FMDV in transgenic dairy cattle or primary transgenic bovine epithelium cells will confer resistance against FMDV challenge. PRINCIPAL FINDING: Here we constructed three recombinant lentiviral vectors containing shRNA against VP2 (RNAi-VP2, VP3 (RNAi-VP3, or VP4 (RNAi-VP4 of FMDV, and found that all of them strongly suppressed the transient expression of a FLAG-tagged viral gene fusion protein in 293T cells. In BHK-21 cells, RNAi-VP4 was found to be more potent in inhibition of viral replication than the others with over 98% inhibition of viral replication. Therefore, recombinant lentiviral vector RNAi-VP4 was transfected into bovine fetal fibroblast cells to generate transgenic nuclear donor cells. With subsequent somatic cell cloning, we generated forty transgenic blastocysts, and then transferred them to 20 synchronized recipient cows. Three transgenic bovine fetuses were obtained after pregnant period of 4 months, and integration into chromosome in cloned fetuses was confirmed by Southern hybridization. The primary tongue epithelium cells of transgenic fetuses were isolated and inoculated with 100 TCID(50 of FMDV, and it was observed that shRNA significantly suppressed viral RNA synthesis and inhibited over 91% of viral replication after inoculation of FMDV for 48 h. CONCLUSION: RNAi-VP4 targeting viral VP4 gene appears to prevent primary epithelium cells of transgenic bovine fetus from FMDV infection, and it could be a candidate shRNA used for cultivation of transgenic cattle against FMDV.

  15. Natural Pigment-Based Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    A.R. Hernández-Martínez

    2012-03-01

    Full Text Available The performance of dye-sensitized solar cells (DSSC based on natural dyes extracted from five different sources is reported. These are inexpensive, have no nutritional use, and are easy to find in Mexico. The solar cells were assembled using a thin film and a TiO2 mesoporous film on ITO-coated glass; these films were characterized by FTIR. The extracts were characterized using UV–Vis and typical I-V curves were obtained for the cells. The best performance was for Punica Granatum with a solar energy conversion efficiency of 1.86%, with a current density Jsc of 3.341 mA/cm2using an incident irradiation of 100 mW/cm2 at 25 ºC.

  16. The Apical Localization of Na+, K+-ATPase in Cultured Human Retinal Pigment Epithelial Cells Depends on Expression of the β2 Subunit

    Science.gov (United States)

    Lobato-Álvarez, Jorge A.; Roldán, María L.; López-Murillo, Teresa del Carmen; González-Ramírez, Ricardo; Bonilla-Delgado, José; Shoshani, Liora

    2016-01-01

    Na+, K+-ATPase, or the Na+ pump, is a key component in the maintenance of the epithelial phenotype. In most epithelia, the pump is located in the basolateral domain. Studies from our laboratory have shown that the β1 subunit of Na+, K+-ATPase plays an important role in this mechanism because homotypic β1-β1 interactions between neighboring cells stabilize the pump in the lateral membrane. However, in the retinal pigment epithelium (RPE), the Na+ pump is located in the apical domain. The mechanism of polarization in this epithelium is unclear. We hypothesized that the apical polarization of the pump in RPE cells depends on the expression of its β2 subunit. ARPE-19 cells cultured for up to 8 weeks on inserts did not polarize, and Na+, K+-ATPase was expressed in the basolateral membrane. In the presence of insulin, transferrin and selenic acid (ITS), ARPE-19 cells cultured for 4 weeks acquired an RPE phenotype, and the Na+ pump was visible in the apical domain. Under these conditions, Western blot analysis was employed to detect the β2 isoform and immunofluorescence analysis revealed an apparent apical distribution of the β2 subunit. qPCR results showed a time-dependent increase in the level of β2 isoform mRNA, suggesting regulation at the transcriptional level. Moreover, silencing the expression of the β2 isoform in ARPE-19 cells resulted in a decrease in the apical localization of the pump, as assessed by the mislocalization of the α2 subunit in that domain. Our results demonstrate that the apical polarization of Na+, K+-ATPase in RPE cells depends on the expression of the β2 subunit. PMID:27774068

  17. The Apical Localization of Na+, K+-ATPase in Cultured Human Retinal Pigment Epithelial Cells Depends on Expression of the β2 Subunit

    Directory of Open Access Journals (Sweden)

    Jorge Lobato Álvarez

    2016-10-01

    Full Text Available Na+, K+-ATPase, or the Na+ pump, is a key component in the maintenance of the epithelial phenotype. In most epithelia, the pump is located in the basolateral domain. Studies from our laboratory have shown that the β1 subunit of Na+, K+-ATPase plays an important role in this mechanism because homotypic β1-β1 interactions between neighboring cells stabilize the pump in the lateral membrane. However, in the retinal pigment epithelium (RPE, the Na+ pump is located in the apical domain. The mechanism of polarization in this epithelium is unclear. We hypothesized that the apical polarization of the pump in RPE cells depends on the expression of its β2 subunit. ARPE-19 cells cultured for up to 8 weeks on inserts did not polarize, and Na+, K+-ATPase was expressed in the basolateral membrane. In the presence of insulin, transferrin and selenic acid (ITS, ARPE-19 cells cultured for 4 weeks acquired an RPE phenotype, and the Na+ pump was visible in the apical domain. Under these conditions, Western blot analysis was employed to detect the β2 isoform and immunofluorescence analysis revealed an apparent apical distribution of the β2 subunit. qPCR results showed a time-dependent increase in the level of β2 isoform mRNA, suggesting regulation at the transcriptional level. Moreover, silencing the expression of the β2 isoform in ARPE-19 cells resulted in a decrease in the apical localization of the pump, as assessed by the mislocalization of the α2 subunit in that domain. Our results demonstrate that the apical polarization of Na+, K+-ATPase in RPE cells depends on the expression of the β2 subunit.

  18. Diverse regulation of retinal pigment epithelium phagocytosis of photoreceptor outer segments by calcium-independent phospholipase A₂, group VIA and secretory phospholipase A₂, group IB

    DEFF Research Database (Denmark)

    Zhan, Chen; Wang, Jinmei; Kolko, Miriam

    2012-01-01

    the role of iPLA(2)-VIA in RPE phagocytosis of POS, experiments with iPLA(2)-VIA vector transfection, iPLA(2)-VIA(-/-) knockout (KO) mice, and iPLA(2)-VIA inhibition by bromoenol lactone (BEL) were done. Exogenous addition of sPLA(2)-IB was used to investigate the role of sPLA(2)-IB in RPE phagocytosis...... and in RPE from KO mice. Exogenous addition of enzymatically active and inactive sPLA(2)-IB reduced phagocytosis in ARPE-19 and primary mouse RPE cells. Finally, sPLA(2)-IB did not seem to affect the iPLA(2)-VIA promoter. CONCLUSION: The present study confirms the involvement of iPLA(2)-VIA in efficient RPE...

  19. Histological and electrophysiological properties of crypt cells from the olfactory epithelium of the marine teleost Trachurus symmetricus.

    Science.gov (United States)

    Schmachtenberg, Oliver

    2006-03-01

    Crypt cells from the olfactory epithelium of the Pacific jack mackerel Trachurus symmetricus were characterized by light and electron microscopy and analyzed in dissociation with the patch-clamp technique in its cell-attached, perforated patch and normal whole-cell mode. Isolated crypt cells remained united with their supporting cells, and both were electrically coupled through gap junctions. Under voltage-clamp, depolarizing voltage steps triggered a transient sodium current, a sustained calcium current, and two types of potassium currents with fast and slow inactivation kinetics. No calcium-dependent potassium current could be observed. The sodium current was blocked by saxitoxin, the calcium current by cobalt and furnidipine, and the potassium currents by tetraethylammonium chloride. In the cell-attached configuration, crypt cells displayed spontaneous spike activity and responded to amino acid solutions with dose-dependent excitation, followed by a period of spike inhibition. These first recordings of individual crypt cells provide the basis for future studies of their odorant specificity, transduction mechanism, and overall function in the fish olfactory epithelium.

  20. HAIR CELL-LIKE CELL GENERATION INDUCED BY NATURE CULTURE OF ADULT RAT AUDITORY EPITHELIUM

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Hair cells are the mechanosensory cells thatconvert sound and motion signals into electrical i m-pulses in cochlear and vestibular end organs of innerear.Although mature mammals nor mally do notgenerate new hair cells,recentin vivoandin vitrostudies have demonstrated mitotic activity and i m-mature-looking hair cells in mammalian vestibularepithelia after exposure to ototoxic drugs[1-3],sug-gesting that vestibular hair cell regeneration inmammals may be inducible.However,the possibil-ity of auditory hair ce...

  1. [Injury and reparative regeneration of the oral mucosal epithelium after cytostatic drugs administration (tissue, cell and molecular mechanisms)].

    Science.gov (United States)

    Bykov, V L; Leont'eva, I V

    2011-01-01

    This paper presents the systematized summary of current literature data and the authors' own findings on the regularities of human and animal surface oral mucosal epithelium (OME) injury caused by cytostatic drugs (CSD) administration, and on the ways of its regeneration after the cytostatic chemotherapy (CSCT) discontinuation. Tissue, cell and molecular mechanisms of CSCT effects on OME, are described. The direct effects of CSD included the epithelial layer attenuation with the derangement of its architecture, epitheliocyte proliferation suppression, apoptosis activation, and differentiation disturbances (involving the broad spectrum of cytological, cytochemical, ultrastructural and molecular-biological changes). In severe cases, these processes resulted in the loss of the epithelial layer integrity with the development of ulceration. Complete epithelial regeneration requires a long period after the CSCT discontinuation. Indirect effects of CSD on OME are associated with the microbial invasion and the diffusion of microbial vital activity products into the epithelium with concurrent leukopenia, immunosuppression and decreased salivary secretion.

  2. Blockage of Notch Signaling Inhibits the Migration and Proliferation of Retinal Pigment Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Weiwei Liu

    2013-01-01

    Full Text Available The Notch signaling is an evolutionarily conserved cell-cell communication pathway that plays critical roles in the proliferation, survival, apoptosis, and fate determination of mammalian cells. Retinal pigment epithelial (RPE cells are responsible for supporting the function of the neural retina and maintaining vision. This study investigated the function of Notch signaling in RPE cells. We found that the members of the Notch signaling pathway components were differentially expressed in RPE cells. Furthermore, blockage of Notch signaling inhibited the migration and proliferation of RPE cells and reduced the expression levels of certain Notch signaling target genes, including HES1, MYC, HEY2, and SOX9. Our data reveal a critical role of Notch signaling in RPE cells, suggesting that targeting Notch signaling may provide a novel approach for the treatment of ophthalmic diseases related to RPE cells.

  3. Tattoo Pigments Are Observed in the Kupffer Cells of the Liver Indicating Blood-Borne Distribution of Tattoo Ink.

    Science.gov (United States)

    Sepehri, Mitra; Sejersen, Tobias; Qvortrup, Klaus; Lerche, Catharina M; Serup, Jørgen

    2017-01-01

    Tattoo pigments are deposited in the skin and known to distribute to regional lymph nodes. Tattoo pigments are small particles and may be hypothesized to reach the blood stream and become distributed to peripheral organs. This has not been studied in the past. The aim of the study was to trace tattoo pigments in internal organs in mice extensively tattooed with 2 different tattoo ink products. Three groups of mice were studied, i.e., 10 tattooed black, 10 tattooed red, and 5 untreated controls. They were tattooed on the entire back with commercial tattoo inks, black and red. Mice were sacrificed after 1 year. Samples were isolated from tattooed skin, lymph nodes, liver, spleen, kidney, and lung. Samples were examined for deposits of tattoo pigments by light microscopy and transmission electron microscopy (TEM). TEM identified intracellular tattoo pigments in the skin and in lymph nodes. TEM in both groups of tattooed mice showed tattoo pigment deposits in the Kupffer cells in the liver, which is a new observation. TEM detected no pigment in other internal organs. Light microscopy showed dense pigment in the skin and in lymph nodes but not in internal organs. The study demonstrated black and red tattoo pigment deposits in the liver; thus, tattoo pigment distributed from the tattooed skin via the blood stream to this important organ of detoxification. The finding adds a new dimension to tattoo pigment distribution in the body, i.e., as observed via the blood in addition to the lymphatic pathway. © 2017 S. Karger AG, Basel.

  4. Single cell sequencing reveals heterogeneity within ovarian cancer epithelium and cancer associated stromal cells.

    Science.gov (United States)

    Winterhoff, Boris J; Maile, Makayla; Mitra, Amit Kumar; Sebe, Attila; Bazzaro, Martina; Geller, Melissa A; Abrahante, Juan E; Klein, Molly; Hellweg, Raffaele; Mullany, Sally A; Beckman, Kenneth; Daniel, Jerry; Starr, Timothy K

    2017-03-01

    The purpose of this study was to determine the level of heterogeneity in high grade serous ovarian cancer (HGSOC) by analyzing RNA expression in single epithelial and cancer associated stromal cells. In addition, we explored the possibility of identifying subgroups based on pathway activation and pre-defined signatures from cancer stem cells and chemo-resistant cells. A fresh, HGSOC tumor specimen derived from ovary was enzymatically digested and depleted of immune infiltrating cells. RNA sequencing was performed on 92 single cells and 66 of these single cell datasets passed quality control checks. Sequences were analyzed using multiple bioinformatics tools, including clustering, principle components analysis, and geneset enrichment analysis to identify subgroups and activated pathways. Immunohistochemistry for ovarian cancer, stem cell and stromal markers was performed on adjacent tumor sections. Analysis of the gene expression patterns identified two major subsets of cells characterized by epithelial and stromal gene expression patterns. The epithelial group was characterized by proliferative genes including genes associated with oxidative phosphorylation and MYC activity, while the stromal group was characterized by increased expression of extracellular matrix (ECM) genes and genes associated with epithelial-to-mesenchymal transition (EMT). Neither group expressed a signature correlating with published chemo-resistant gene signatures, but many cells, predominantly in the stromal subgroup, expressed markers associated with cancer stem cells. Single cell sequencing provides a means of identifying subpopulations of cancer cells within a single patient. Single cell sequence analysis may prove to be critical for understanding the etiology, progression and drug resistance in ovarian cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Photosynthetic pigments, cell extrusion and relative leaf water content of the castor bean under silicon and salinity

    National Research Council Canada - National Science Library

    Ferraz, Rener L. de S; Magalhães, Ivomberg D; Beltrão, Napoleão E. de M; Melo, Alberto S. de; Brito Neto, Jósé F. de; Rocha, Maria do S

    2015-01-01

    .... Thus, this study aimed to evaluate the contents of photosynthetic pigments, cell membrane extrusion and the relative water content in the leaves of the castor bean cultivar 'BRS Energia' under...

  6. 3,3'-Diindolylmethane inhibits VEGF expression through the HIF-1α and NF-κB pathways in human retinal pigment epithelial cells under chemical hypoxic conditions.

    Science.gov (United States)

    Park, Hongzoo; Lee, Dae-Sung; Yim, Mi-Jin; Choi, Yung Hyun; Park, Saegwang; Seo, Su-Kil; Choi, Jung Sik; Jang, Won Hee; Yea, Sung Su; Park, Won Sun; Lee, Chang-Min; Jung, Won-Kyo; Choi, Il-Whan

    2015-07-01

    Oxidative stress in the retinal pigment epithelium (RPE) can lead to the pathological causes of age-related macular degeneration (AMD). Hypoxia induces oxidative damage in retinal pigment epithelial cells (RPE cells). In this study, we investigated the capacity of 3,3'-diindolylmethane (DIM) to reduce the expression of vascular endothelial growth factor (VEGF) under hypoxic conditions, as well as the molecular mechanisms involved. Human RPE cells (ARPE-19 cells) were treated with cobalt chloride (CoCl2, 200 µM) and/or DIM (10 and 20 µM). The production of VEGF was measured by enzyme-linked immunosorbent assay. The translocation of hypoxia-inducible factor-1α (HIF-1α) and nuclear factor-κB (NF-κB) was determined by western blot analysis. The binding activity of HIF-1α and NF-κB was analyzed by electrophoretic mobility shift assay. The phosphorylation levels of mitogen-activated protein kinases (MAPKs) were measured by western blot analysis. The levels of mitochondrial reactive oxygen species (ROS) were detected by fluorescence microplate assay. The results revealed that DIM significantly attenuated the CoCl2-induced expression of VEGF in the ARPE-19 cells. The CoCl2-induced translocation and activation of HIF-1α and NF-κB were also attenuated by treatment with DIM. In addition, DIM inhibited the CoCl2-induced activation of p38 MAPK in the ARPE-19 cells. Pre-treatment with YCG063, a mitochondrial ROS inhibitor, led to the downregulation of the CoCl2-induced production of VEGF by suppressing HIF-1α and NF-κB activity. Taken together, the findings of our study demonstrate that DIM inhibits the CoCl2-induced production of VEGF by suppressing mitochondrial ROS production, thus attenuating the activation of HIF-1α and p38 MAPK/NF-κB.

  7. Generation of functional thymic epithelium from human embryonic stem cells that supports host T cell development.

    Science.gov (United States)

    Parent, Audrey V; Russ, Holger A; Khan, Imran S; LaFlam, Taylor N; Metzger, Todd C; Anderson, Mark S; Hebrok, Matthias

    2013-08-01

    Inducing immune tolerance to prevent rejection is a key step toward successful engraftment of stem-cell-derived tissue in a clinical setting. Using human pluripotent stem cells to generate thymic epithelial cells (TECs) capable of supporting T cell development represents a promising approach to reach this goal; however, progress toward generating functional TECs has been limited. Here, we describe a robust in vitro method to direct differentiation of human embryonic stem cells (hESCs) into thymic epithelial progenitors (TEPs) by precise regulation of TGFβ, BMP4, RA, Wnt, Shh, and FGF signaling. The hESC-derived TEPs further mature into functional TECs that support T cell development upon transplantation into thymus-deficient mice. Importantly, the engrafted TEPs produce T cells capable of in vitro proliferation as well as in vivo immune responses. Thus, hESC-derived TEP grafts may have broad applications for enhancing engraftment in cell-based therapies as well as restoring age- and stress-related thymic decline.

  8. Lycium barbarum polysaccharides protected human retinal pigment epithelial cells against oxidative stressinduced apoptosis

    Institute of Scientific and Technical Information of China (English)

    Lian; Liu; Wei; Lao; Qing-Shan; Ji; Zhi-Hao; Yang; Guo-Cheng; Yu; Jing-Xiang; Zhong

    2015-01-01

    AIM: To investigate the protective effect and its mechanism of lycium barbarum polysaccharides(LBP)against oxidative stress-induced apoptosis in human retinal pigment epithelial cells.METHODS: ARPE-19 cells, a human retinal pigment epithelial cell lines, were exposed to different concentrations of H2O2 for 24h, then cell viability was measured by Cell Counting Kit-8(CCK-8) assay to get the properly concentration of H2O2 which can induce half apoptosis of APRE-19. With different concentrations of LBP pretreatment, the ARPE-19 cells were then exposed to appropriate concentration of H2O2, cell apoptosis was detected by flow cytometric analysis. Expression levels of Bcl-2 and Bax were measured by real time quantitative polymerase chain reaction(RT-PCR) technique.RSULTS: LBP significantly reduced the H2O2-induced ARPE-19 cells’ apoptosis. LBP inhibited the H2O2-induced down-regulation of Bcl-2 and up-regulation of Bax.CONCLUSION: LBP could protect ARPE-19 cells from H2O2-induced apoptosis. The Bcl-2 family had relationship with the protective effects of LBP.

  9. Transplantation of human limbal cells cultivated on amniotic membrane for reconstruction of rat corneal epithelium after alkaline burn

    Institute of Scientific and Technical Information of China (English)

    SONG E; YANG Wei; CUI Zhi-hua; DONG Yu; SUI Dong-ming; GUAN Xiao-kang; MA Yang-ling

    2005-01-01

    Background The transplantation of limbal epithelial cells cultivated on amniotic membrane is a newly developed treatment for limbal stem cell deficiency. The purpose of our study was to investigate the biological characteristics of limbal epithelial cells and evaluate the effect of transplantation of cultivated human limbal epithelial cells on ocular surface reconstruction in limbal stem cell deficiency rat model. Methods Human limbal cells were isolated and cultivated in vitro. Cytokertins 3, 12, and 19 (K3, K12 and K19) and p63 were detected by immunofluorescent staining or RT-PCR. BrdU labelling test was used to identify the slow cycling cells in the cultures. Limbal stem cell deficiency was established in rat cornea by alkali burn. Two weeks after injury, the rats received transplants of human limbal stem cells cultivated on amniotic membrane carrier. The therapeutic effect was evaluated by slit lamp observation, Hemotoxin and Eosin (HE) staining and immunofluorescent staining.Results On day 7 in primary culture, p63 and K19 were strongly expressed by most cells but only a few cells expressed K3. On days 14 and 21, p63 and K19 were still expressed by a majority of cells, but the expressive intensity of p63 decreased in a number of cells, while the proportion of K3 positive cells increased slightly and some cells coexpressed p63 and K3. RT-PCR showed that gene expression of both p63 and K12 were positive in cultivated limbal cells, but in mature superficial epithelial cells, only K12 was detected. BrdU labelling test showed that most cells were labelled with BrdU after 7 days' labelling and BrdU label retaining cells were observed after chasing for 21 days with BrdU free medium. For in vivo test, slit lamp observation, HE staining and immunofluorescent staining showed that the rats receiving transplant of human limbal stem cells cultivated on amniotic membrane grew reconstructed corneas with intact epithelium, improved transparency and slight or no

  10. Controlling gene expression in mice with tetracycline: application in pigment cell research.

    Science.gov (United States)

    Shin, M K

    2000-10-01

    Genetic manipulation techniques are widely used in mice to study the functions of genes. The most common strategy for assessing in vivo function involves making irreversible changes in the genome by homologous recombination. To complement this approach, a number of systems have been developed that allow specific and controlled expression of a gene. One of the more versatile and promising systems is based on the tetracycline (tet) responsive bacterial tetracycline repressor (TetR). In recent years, the tet system has proven to be a valuable method for understanding the function of genes involved in a number of physiological processes, including mouse models for human diseases such as cancer and neurological and pigment disorders. This review will highlight the power and elegance of the tet system by focusing on its utility in the study of two pigment cell-related biological problems, the pathogenesis of melanomas and melanocyte development in the embryo.

  11. Interaction of minoxidil with pigment in cells of the hair follicle: an example of binding without apparent biological effects.

    Science.gov (United States)

    Buhl, A E; Kawabe, T T; MacCallum, D K; Waldon, D J; Knight, K A; Johnson, G A

    1992-01-01

    To identify minoxidil target cells in hair follicles we followed the uptake of radiolabeled drug in mouse vibrissae follicles both in vitro and in vivo. Autoradiography showed that both 3H-minoxidil and 3H-minoxidil sulfate accumulated in the differentiating epithelial matrix cells superior to the dermal papilla, a distribution similar to that of pigment. Minoxidil localized in melanocytes, melanocyte processes, and areas of greater melanin concentrations within the epithelial cells. Although uptake of minoxidil was significantly less in unpigmented follicles, the drug stimulated proliferation and differentiation of both pigmented and unpigmented follicles. Labeled minoxidil bound to Sepia melanin and was displaced with unlabeled minoxidil and other electron donor drugs. This interaction with melanin acts as a targeting mechanism of minoxidil to pigmented hair follicles but has no apparent functional significance in hair growth. This work illustrates how measurement of drugs in hair may be biased by pigmentation.

  12. Modification of Isolation and Culture of Human Retinal Pigment Epithelial Cells

    Institute of Scientific and Technical Information of China (English)

    ZhengJL; GuoY

    1999-01-01

    Purpose:To modify the isolation of human retinal pigment pithelial(RPE)cells and to increase the purification and production of cultured RPE cells.Methods:The human eyecups were fixed on a fubber holder.After digestion by trypsin,RPE cells were collected,then cultured and identified by morphology,immunohistochemistry and electron microscopy.Results:The cultured RPE cells grew actively in the early stage with transparent nucleus and abundant melanin particles in cytoplasm.These cells were positive in DOPA oxidase reaction and in anti-pancytokeratin antibody staining.Cellular microvilli and tight junctions could be seen through transmission electrom microscopy.Conclusion:We developed a rubber holder to fix the eyecup.Using this holder,more and purer cultured RPE cells can be obtained.These cultured REP cells are similar to those in vivo in morphology and immunohistochemical staining.

  13. [Hepatoma 27 cells and the epithelium of the large intestine in rats contain the identical set of prekeratin proteins].

    Science.gov (United States)

    Troianovskiĭ, S M; Krutovskikh, V A; Bannikov, G A

    1984-08-01

    It has been shown by means of the immunoblot technique in combination with monoclonal antibodies and peptide mapping that hepatocytes, hepatoma 27 cells, and rat colon enterocytes exhibit a common prekeratin protein with a molecular weight of 49 kD (PK49). This protein and vimentin, a protein contained by intermediate filaments of mesenchymal cells, share at least one antigenic determinant. The generally accepted procedure for prekeratin purification leads to a more or less pronounced degradation of PK49. The degree of degradation is dependent on the type of the tissue extracted. High heterogenicity of prekeratin polypeptides described elsewhere might be due partly to such a degradation process. In addition to PK49, hepatoma 27 cells, absorbing, goblet and proliferating cells of the colon demonstrated three more prekeratin proteins: two major (PK55 and PK40) and one minor (PK53). Monoclonal antibodies not reacting with PK49 do not recognize PK55, PK53 and PK40. PK55, PK49 and PK40 of hepatoma 27 are identical to the appropriate proteins of the colonic epithelium as judged by peptide mapping. Thus, the cells of the hepatocyte origin are able to synthesize the same prekeratins as the colonic epithelium.