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Sample records for human rpe cells

  1. Amniotic fluid promotes the appearance of neural retinal progenitors and neurons in human RPE cell cultures.

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    Davari, Maliheh; Soheili, Zahra-Soheila; Ahmadieh, Hamid; Sanie-Jahromi, Fateme; Ghaderi, Shima; Kanavi, Mozhgan Rezaei; Samiei, Shahram; Akrami, Hassan; Haghighi, Massoud; Javidi-Azad, Fahimeh

    2013-01-01

    Retinal pigment epithelial (RPE) cells are capable of differentiating into retinal neurons when induced by the appropriate growth factors. Amniotic fluid contains a variety of growth factors that are crucial for the development of a fetus. In this study, the effects of human amniotic fluid (HAF) on primary RPE cell cultures were evaluated. RPE cells were isolated from the globes of postnatal human cadavers. The isolated cells were plated and grown in DMEM/F12 with 10% fetal bovine serum. To confirm the RPE identity of the cultured cells, they were immunocytochemically examined for the presence of the RPE cell-specific marker RPE65. RPE cultures obtained from passages 2-7 were treated with HAF and examined morphologically for 1 month. To determine whether retinal neurons or progenitors developed in the treated cultures, specific markers for bipolar (protein kinase C isomer α, PKCα), amacrine (cellular retinoic acid-binding protein I, CRABPI), and neural progenitor (NESTIN) cells were sought, and the amount of mRNA was quantified using real-time PCR. Treating RPE cells with HAF led to a significant decrease in the number of RPE65-positive cells, while PKCα- and CRABPI-positive cells were detected in the cultures. Compared with the fetal bovine serum-treated cultures, the levels of mRNAs quantitatively increased by 2-, 20- and 22-fold for NESTIN, PKCα, and CRABPI, respectively. The RPE cultures treated with HAF established spheres containing both pigmented and nonpigmented cells, which expressed neural progenitor markers such as NESTIN. This study showed that HAF can induce RPE cells to transdifferentiate into retinal neurons and progenitor cells, and that it provides a potential source for cell-based therapies to treat retinal diseases.

  2. Human RPE Stem Cells Grown into Polarized RPE Monolayers on a Polyester Matrix Are Maintained after Grafting into Rabbit Subretinal Space

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    Boris V. Stanzel

    2014-01-01

    Full Text Available Transplantation of the retinal pigment epithelium (RPE is being developed as a cell-replacement therapy for age-related macular degeneration. Human embryonic stem cell (hESC and induced pluripotent stem cell (iPSC-derived RPE are currently translating toward clinic. We introduce the adult human RPE stem cell (hRPESC as an alternative RPE source. Polarized monolayers of adult hRPESC-derived RPE grown on polyester (PET membranes had near-native characteristics. Trephined pieces of RPE monolayers on PET were transplanted subretinally in the rabbit, a large-eyed animal model. After 4 days, retinal edema was observed above the implant, detected by spectral domain optical coherence tomography (SD-OCT and fundoscopy. At 1 week, retinal atrophy overlying the fetal or adult transplant was observed, remaining stable thereafter. Histology obtained 4 weeks after implantation confirmed a continuous polarized human RPE monolayer on PET. Taken together, the xeno-RPE survived with retained characteristics in the subretinal space. These experiments support that adult hRPESC-derived RPE are a potential source for transplantation therapies.

  3. The effects of platelet gel on cultured human retinal pigment epithelial (hRPE cells

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    Sahar Balagholi

    2017-11-01

    Full Text Available The positive role of platelet gel (PG in tissue regeneration is well known, however, other characteristics of PG still remain to be determined. We investigated cellular and molecular changes in cultured human retinal pigment epithelial (hRPE cells when treated with different concentrations of PG named PG1, PG2, and PG3. hRPE cells were isolated from donor eyes of two newborn children, within 24 hours after their death. The cells were treated with three concentrations of PG for 7 days: 3 × 104/ml (PG1, 6 × 104/ml (PG2, and 9 × 104/ml (PG3. Fetal bovine serum was used as a control. Immunocytochemistry was performed with anti-RPE65 (H-85, anti-Cytokeratin 8/18 (NCL-5D3, and anti-PAX6 antibody. We used MTT assay to determine cell viability. Gene expressions of PAX6, MMP2, RPE65, ACTA2, MKI67, MMP9, and KDR were analyzed using real-time PCR. A significant increase in viability was observed for PG3-treated cells compared to control (p = 0.044 and compared to PG1 group (p = 0.027, on day 7. Cellular elongation together with dendritiform extensions were observed in PG-treated cells on days 1 and 3, while epithelioid morphology was observed on day 7. All cells were immunoreactive for RPE65, cytokeratin 8/18, and PAX6. No significant change was observed in the expression of MKI67 and PAX6, but the expressions of MMP2, MMP9, ACTA2, and KDR were significantly higher in PG2-treated cells compared to controls (p < 0.05. Our results indicate that increased concentration of PG and extended exposure time have positive effects on viability of hRPE cells. PG may be useful for hRPE cell encapsulation in retinal cell replacement therapy.

  4. AAV delivery of GRP78/BiP promotes adaptation of human RPE cell to ER stress.

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    Ghaderi, Shima; Ahmadian, Shahin; Soheili, Zahra-Soheila; Ahmadieh, Hamid; Samiei, Shahram; Kheitan, Samira; Pirmardan, Ehsan R

    2018-02-01

    Adeno associated virus (AAV)-mediated gene delivery of GRP78 (78 kDa glucose-regulated protein) attenuates the condition of endoplasmic reticulum (ER) stress and prevents apoptotic loss of photoreceptors in Retinitis pigmentosa (RP) rats. In the current study we overexpressed Grp78 with the help of AAV-2 in primary human retinal pigmented epithelium (hRPE) cell cultures and examined its effect on cell response to ER stress. The purpose of this work was studying potential stimulating effect of GRP78 on adaptation/pro-survival of hRPE cells under ER stress, as an in vitro model for RPE degeneration. To investigate the effect of Grp78 overexpression on unfolded protein response (UPR) markers under ER stress, hRPE primary cultures were transduced by recombinant virus rAAV/Grp78, and treated with ER stressor drug, tunicamycin. Expression changes of four UPR markers including GRP78, PERK, ATF6α, and GADD153/CHOP, were assessed by real-time PCR and western blotting. We found that GRP78 has a great contribution in modulation of UPR markers to favor adaptive response in ER-stressed hRPE cells. In fact, GRP78 overexpression affected adaptation and apoptotic phases of early UPR, through enhancement of two master regulators/ER stress sensors (PERK and ATF6α) and down-regulation of a key pro-apoptotic cascade activator (GADD153/CHOP). Together these findings demonstrate the promoting effect of GRP78 on adaptation/pro-survival of hRPE cells under ER stress. This protein with anti-apoptotic actions in the early UPR and important role in cell fate regulation, can be recruited as a useful candidate for future investigations of RPE degenerative diseases. © 2017 Wiley Periodicals, Inc.

  5. Simultaneous application of bevacizumab and anti-CTGF antibody effectively suppresses proangiogenic and profibrotic factors in human RPE cells.

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    Bagheri, Abouzar; Soheili, Zahra-Soheila; Ahmadieh, Hamid; Samiei, Shahram; Sheibani, Nader; Astaneh, Shamila Darvishalipour; Kanavi, Mozhgan Rezaei; Mohammadian, Azam

    2015-01-01

    Retinal pigment epithelial (RPE) cells play key roles in the development of choroidal neovascularization and subsequent fibrosis. We investigated the impact of bevacizumab, antihuman vascular endothelial growth factor (VEGF) antibody, and anticonnective tissue growth factor (anti-CTGF) neutralizing antibody, individually or in combination, on proangiogenic and profibrotic properties of RPE cells. Primary cultures of human RPE cells were incubated with different concentrations of bevacizumab (0.25, 0.5, and 0.8 mg/ml) and/or anti-CTGF (10 μg/ml), and cell proliferation and apoptosis were determined. Expression and activity of proangiogenic and profibrotic genes including matrix metalloproteinases (MMP)-2 and 9, VEGFA, CTGF, vascular endothelial growth factor receptor-1 (VEGFR-1), cathepsin D, tissue inhibitor of metalloproteinases (TIMP) -1 and -2, and alpha smooth muscle actin (α-SMA) were assessed with slot blot, real-time RT-PCR, and zymography. Bevacizumab alone inhibited proliferation of RPE cells while anti-CTGF or bevacizumab and anti-CTGF combined had no inhibitory effect in this regard. Bevacizumab increased MMP-2, MMP-9, and cathepsin D but decreased VEGFA and VEGFR-1 expression. The CTGF level was increased by using 0.25 mg/ml bevacizumab but decreased at the 0.8 mg/ml concentration of bevacizumab. Treatment with anti-CTGF antibody decreased MMP-2 expression whereas combined treatment with bevacizumab and anti-CTGF resulted in decreased expression of MMP-2, TIMP-1, cathepsin D, VEGFA, CTGF, and α-SMA in the treated cultures. Treatment of RPE cells with the combination of bevacizumab and anti-CTGF could effectively suppress the proangiogenic and profibrotic activity of RPE cells.

  6. The influence of rAAV2-mediated SOX2 delivery into neonatal and adult human RPE cells; a comparative study.

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    Ezati, Razie; Etemadzadeh, Azadeh; Soheili, Zahra-Soheila; Samiei, Shahram; Ranaei Pirmardan, Ehsan; Davari, Malihe; Najafabadi, Hoda Shams

    2018-02-01

    Cell replacement is a promising therapy for degenerative diseases like age-related macular degeneration (AMD). Since the human retina lacks regeneration capacity, much attention has been directed toward persuading for cells that can differentiate into retinal neurons. In this report, we have investigated reprogramming of the human RPE cells and concerned the effect of donor age on the cellular fate as a critical determinant in reprogramming competence. We evaluated the effect of SOX2 over-expression in human neonatal and adult RPE cells in cultures. The coding region of human SOX2 gene was cloned into adeno-associated virus (AAV2) and primary culture of human neonatal/adult RPE cells were infected by recombinant virus. De-differentiation of RPE to neural/retinal progenitor cells was investigated by quantitative real-time PCR and ICC for neural/retinal progenitor cells' markers. Gene expression analysis showed 80-fold and 12-fold over-expression for SOX2 gene in infected neonatal and adult hRPE cells, respectively. The fold of increase for Nestin in neonatal and adult hRPE cells was 3.8-fold and 2.5-fold, respectively. PAX6 expression was increased threefold and 2.5-fold in neonatal/adult treated cultures. Howbeit, we could not detect rhodopsin, and CHX10 expression in neonatal hRPE cultures and expression of rhodopsin in adult hRPE cells. Results showed SOX2 induced human neonatal/adult RPE cells to de-differentiate toward retinal progenitor cells. However, the increased number of PAX6, CHX10, Thy1, and rhodopsin positive cells in adult hRPE treated cultures clearly indicated the considerable generation of neuro-retinal terminally differentiated cells. © 2017 Wiley Periodicals, Inc.

  7. Mouse Retinal Pigmented Epithelial Cell Lines retain their phenotypic characteristics after transfection with Human Papilloma Virus: A new tool to further the study of RPE biology

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    Catanuto, Paola; Espinosa-Heidmann, Diego; Pereira-Simon, Simone; Sanchez, Patricia; Salas, Pedro; Hernandez, Eleut; Cousins, Scott W.; Elliot, Sharon J.

    2009-01-01

    Development of immortalized mouse retinal pigmented epithelial cell (RPE) lines that retain many of their in vivo phenotypic characteristics, would aid in studies of ocular diseases including age related macular degeneration (AMD). RPE cells were isolated from 16 month old (estrogen receptor knockout) ERKOα and ERKOβ mice and their C57Bl/6 wild type littermates. RPE65 and cellular retinaldehyde binding protein (CRALBP) expression, in vivo markers of RPE cells, were detected by real-time RT-PCR and western analysis. We confirmed the presence of epithelial cell markers, ZO1, cytokeratin 8 and 18 by immunofluorescence staining. In addition, we confirmed the distribution of actin filaments and the expression of ezrin. To develop cell lines, RPE cells were isolated, propagated and immortalized using human papilloma virus (HPV) 16 (E6/E7). RPE-specific markers and morphology were assessed before and after immortalization. In wildtype littermate controls, there was no evidence of any alterations in the parameters that we examined including MMP-2, TIMP-2, collagen type IV, and estrogen receptor (ER) α and ERβ protein expression and ER copy number ratio. Therefore, immortalized mouse RPE cell lines that retain their in vivo phenotype can be isolated from either pharmacologically or genetically manipulated mice, and may be used to study RPE cell biology. PMID:19013153

  8. Two dietary polyphenols, fisetin and luteolin, reduce inflammation but augment DNA damage-induced toxicity in human RPE cells.

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    Hytti, Maria; Szabó, Dora; Piippo, Niina; Korhonen, Eveliina; Honkakoski, Paavo; Kaarniranta, Kai; Petrovski, Goran; Kauppinen, Anu

    2017-04-01

    Plant-derived polyphenols are known to possess anti-inflammatory and antioxidant effects. In recent years, several studies have investigated their potential benefits for treating chronic diseases associated with prolonged inflammation and excessive oxidative stress, such as age-related macular degeneration (AMD). Previously, two polyphenols, fisetin and luteolin, have been reported to increase the survival of retinal pigment epithelial (RPE) cells suffering from oxidative stress as well as decreasing inflammation but the benefits of polyphenol therapy seem to depend on the model system used. Our aim was to analyze the effects of fisetin and luteolin on inflammation and cellular viability in a model of nonoxidative DNA damage-induced cell death in human RPE (hRPE) cells. Pretreatment of ARPE-19 or primary hRPE cells with the polyphenols augmented etoposide-induced cell death as measured by the lactate dehydrogenase and 3-(4,5-dimethyldiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. However, the treatment was able to reduce the release of two proinflammatory cytokines, IL-6 and IL-8, which were determined by enzyme-linked Immunosorbent assay. Analyses of caspase 3 activity, p53 acetylation and SIRT1 protein levels revealed the apoptotic nature of etoposide-evoked cell death and that fisetin and luteolin augmented the etoposide-induced acetylation of p53 and decreased SIRT1 levels. Taken together, our findings suggest that the cytoprotective effects of fisetin and luteolin depend on the stressor they need to combat, whereas their anti-inflammatory potential is sustained over a variety of model systems. Careful consideration of disease pathways will be necessary before fisetin or luteolin can be recommended as therapeutic agents for inflammatory diseases in general and specifically AMD. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Evaluation of RPE65, CRALBP, VEGF, CD68, and tyrosinase gene expression in human retinal pigment epithelial cells cultured on amniotic membrane.

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    Akrami, Hassan; Soheili, Zahra-Soheila; Sadeghizadeh, Majid; Khalooghi, Keynoush; Ahmadieh, Hamid; Kanavi, Mojgan Rezaie; Samiei, Shahram; Pakravesh, Jalil

    2011-06-01

    The retinal pigment epithelium (RPE) plays a key role in the maintenance of the normal functions of the retina. Tissue engineering using amniotic membrane as a substrate to culture RPE cells may provide a promising new strategy to replace damaged RPE. We established a method of culturing RPE cells over the amniotic membrane as a support for their growth and transplantation. The transcription of specific genes involved in cellular function of native RPE, including RPE65, CRALBP, VEGF, CD68, and tyrosinase, were then measured using quantitative real-time PCR. Data showed a considerable increase in transcription of RPE65, CD68, and VEGF in RPE cells cultured on amniotic membrane. The amounts of CRALBP and tyrosinase transcripts were not affected. This may simply indicate that amniotic membrane restricted dedifferentiation of RPE cells in culture. The results suggest that amniotic membrane may be considered as an elective biological substrate for RPE cell culture.

  10. Monomethylfumarate induces γ-globin expression and fetal hemoglobin production in cultured human retinal pigment epithelial (RPE) and erythroid cells, and in intact retina.

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    Promsote, Wanwisa; Makala, Levi; Li, Biaoru; Smith, Sylvia B; Singh, Nagendra; Ganapathy, Vadivel; Pace, Betty S; Martin, Pamela M

    2014-05-13

    Sickle retinopathy (SR) is a major cause of vision loss in sickle cell disease (SCD). There are no strategies to prevent SR and treatments are extremely limited. The present study evaluated (1) the retinal pigment epithelial (RPE) cell as a hemoglobin producer and novel cellular target for fetal hemoglobin (HbF) induction, and (2) monomethylfumarate (MMF) as an HbF-inducing therapy and abrogator of oxidative stress and inflammation in SCD retina. Human globin gene expression was evaluated by RT-quantitative (q)PCR in the human RPE cell line ARPE-19 and in primary RPE cells isolated from Townes humanized SCD mice. γ-Globin promoter activity was monitored in KU812 stable dual luciferase reporter expressing cells treated with 0 to 1000 μM dimethylfumarate, MMF, or hydroxyurea (HU; positive control) by dual luciferase assay. Reverse transcriptase-qPCR, fluorescence-activated cell sorting (FACS), immunofluorescence, and Western blot techniques were used to evaluate γ-globin expression and HbF production in primary human erythroid progenitors, ARPE-19, and normal hemoglobin producing (HbAA) and homozygous β(s) mutation (HbSS) RPE that were treated similarly, and in MMF-injected (1000 μM) HbAA and HbSS retinas. Dihydroethidium labeling and nuclear factor (erythroid-derived 2)-like 2 (Nrf2), IL-1β, and VEGF expression were also analyzed. Retinal pigment epithelial cells express globin genes and synthesize adult and fetal hemoglobin MMF stimulated γ-globin expression and HbF production in cultured RPE and erythroid cells, and in HbSS mouse retina where it also reduced oxidative stress and inflammation. The production of hemoglobin by RPE suggests the potential involvement of this cell type in the etiology of SR. Monomethylfumarate influences multiple parameters consistent with improved retinal health in SCD and may therefore be of therapeutic potential in SR treatment. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  11. Calcium-independent phospholipase A₂, group VIA, is critical for RPE cell survival

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    Kolko, Miriam; Vohra, Rupali; Westlund, Barbro S.

    2014-01-01

    PURPOSE: To investigate the significance of calcium-independent phospholipase A₂, group VIA (iPLA2-VIA), in RPE cell survival following responses to sodium iodate (SI) in cell cultures. METHODS: The human retinal pigment epithelium (RPE) cell line (ARPE-19) cells and primary mouse-RPE cultures were...

  12. TNF-α promotes human retinal pigment epithelial (RPE) cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression through activation of Akt/mTORC1 signaling

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    Wang, Cheng-hu; Cao, Guo-Fan; Jiang, Qin; Yao, Jin

    2012-01-01

    Highlights: ► TNF-α induces MMP-9 expression and secretion to promote RPE cell migration. ► MAPK activation is not critical for TNF-α-induced MMP-9 expression. ► Akt and mTORC1 signaling mediate TNF-α-induced MMP-9 expression. ► SIN1 knockdown showed no significant effect on MMP-9 expression by TNF-α. -- Abstract: Tumor necrosis factor-alpha (TNF-α) promotes in vitro retinal pigment epithelial (RPE) cell migration to initiate proliferative vitreoretinopathy (PVR). Here we report that TNF-α promotes human RPE cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression. Inhibition of MMP-9 by its inhibitor or its neutralizing antibody inhibited TNF-α-induced in vitro RPE cell migration. Reversely, exogenously-added active MMP-9 promoted RPE cell migration. Suppression Akt/mTOR complex 1(mTORC1) activation by LY 294002 and rapamycin inhibited TNF-α-mediated MMP-9 expression. To introduce a constitutively active Akt (CA-Akt) in cultured RPE cells increased MMP-9 expression, and to block mTORC1 activation by rapamycin inhibited its effect. RNA interference (RNAi)-mediated silencing of SIN1, a key component of mTOR complex 2 (mTORC2), had no effect on MMP-9 expression or secretion. In conclusion, this study suggest that TNF-α promotes RPE cell migration by inducing MMP-9 expression through activation of Akt/ mTORC1, but not mTORC2 signaling.

  13. TNF-{alpha} promotes human retinal pigment epithelial (RPE) cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression through activation of Akt/mTORC1 signaling

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    Wang, Cheng-hu; Cao, Guo-Fan [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China); Jiang, Qin, E-mail: Jqin710@vip.sina.com [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China); Yao, Jin, E-mail: dryaojin@yahoo.com [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer TNF-{alpha} induces MMP-9 expression and secretion to promote RPE cell migration. Black-Right-Pointing-Pointer MAPK activation is not critical for TNF-{alpha}-induced MMP-9 expression. Black-Right-Pointing-Pointer Akt and mTORC1 signaling mediate TNF-{alpha}-induced MMP-9 expression. Black-Right-Pointing-Pointer SIN1 knockdown showed no significant effect on MMP-9 expression by TNF-{alpha}. -- Abstract: Tumor necrosis factor-alpha (TNF-{alpha}) promotes in vitro retinal pigment epithelial (RPE) cell migration to initiate proliferative vitreoretinopathy (PVR). Here we report that TNF-{alpha} promotes human RPE cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression. Inhibition of MMP-9 by its inhibitor or its neutralizing antibody inhibited TNF-{alpha}-induced in vitro RPE cell migration. Reversely, exogenously-added active MMP-9 promoted RPE cell migration. Suppression Akt/mTOR complex 1(mTORC1) activation by LY 294002 and rapamycin inhibited TNF-{alpha}-mediated MMP-9 expression. To introduce a constitutively active Akt (CA-Akt) in cultured RPE cells increased MMP-9 expression, and to block mTORC1 activation by rapamycin inhibited its effect. RNA interference (RNAi)-mediated silencing of SIN1, a key component of mTOR complex 2 (mTORC2), had no effect on MMP-9 expression or secretion. In conclusion, this study suggest that TNF-{alpha} promotes RPE cell migration by inducing MMP-9 expression through activation of Akt/ mTORC1, but not mTORC2 signaling.

  14. Differentiation of RPE cells from integration-free iPS cells and their cell biological characterization.

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    Hazim, Roni A; Karumbayaram, Saravanan; Jiang, Mei; Dimashkie, Anupama; Lopes, Vanda S; Li, Douran; Burgess, Barry L; Vijayaraj, Preethi; Alva-Ornelas, Jackelyn A; Zack, Jerome A; Kohn, Donald B; Gomperts, Brigitte N; Pyle, April D; Lowry, William E; Williams, David S

    2017-10-02

    Dysfunction of the retinal pigment epithelium (RPE) is implicated in numerous forms of retinal degeneration. The readily accessible environment of the eye makes it particularly suitable for the transplantation of RPE cells, which can now be derived from autologous induced pluripotent stem cells (iPSCs), to treat retinal degeneration. For RPE transplantation to become feasible in the clinic, patient-specific somatic cells should be reprogrammed to iPSCs without the introduction of reprogramming genes into the genome of the host cell, and then subsequently differentiated into RPE cells that are well characterized for safety and functionality prior to transplantation. We have reprogrammed human dermal fibroblasts to iPSCs using nonintegrating RNA, and differentiated the iPSCs toward an RPE fate (iPSC-RPE), under Good Manufacturing Practice (GMP)-compatible conditions. Using highly sensitive assays for cell polarity, structure, organelle trafficking, and function, we found that iPSC-RPE cells in culture exhibited key characteristics of native RPE. Importantly, we demonstrate for the first time with any stem cell-derived RPE cell that live cells are able to support dynamic organelle transport. This highly sensitive test is critical for RPE cells intended for transplantation, since defects in intracellular motility have been shown to promote RPE pathogenesis akin to that found in macular degeneration. To test their capabilities for in-vivo transplantation, we injected the iPSC-RPE cells into the subretinal space of a mouse model of retinal degeneration, and demonstrated that the transplanted cells are capable of rescuing lost RPE function. This report documents the successful generation, under GMP-compatible conditions, of human iPSC-RPE cells that possess specific characteristics of healthy RPE. The report adds to a growing literature on the utility of human iPSC-RPE cells for cell culture investigations on pathogenicity and for therapeutic transplantation, by

  15. Elucidating the phenomenon of HESC-derived RPE: anatomy of cell genesis, expansion and retinal transplantation.

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    Vugler, Anthony; Carr, Amanda-Jayne; Lawrence, Jean; Chen, Li Li; Burrell, Kelly; Wright, Andrew; Lundh, Peter; Semo, Ma'ayan; Ahmado, Ahmad; Gias, Carlos; da Cruz, Lyndon; Moore, Harry; Andrews, Peter; Walsh, James; Coffey, Peter

    2008-12-01

    Healthy Retinal Pigment Epithelium (RPE) cells are required for proper visual function and the phenomenon of RPE derivation from Human Embryonic Stem Cells (HESC) holds great potential for the treatment of retinal diseases. However, little is known about formation, expansion and expression profile of RPE-like cells derived from HESC (HESC-RPE). By studying the genesis of pigmented foci we identified OTX1/2-positive cell types as potential HESC-RPE precursors. When pigmented foci were excised from culture, HESC-RPE expanded to form extensive monolayers, with pigmented cells at the leading edge assuming a precursor role: de-pigmenting, proliferating, expressing keratin 8 and subsequently re-differentiating. As they expanded and differentiated in vitro, HESC-RPE expressed markers of both developing and mature RPE cells which included OTX1/2, Pax6, PMEL17 and at low levels, RPE65. In vitro, without signals from a developing retinal environment, HESC-RPE could produce regular, polarised monolayers with developmentally important apical and basal features. Following transplantation of HESC-RPE into the degenerating retinal environment of Royal College of Surgeons (RCS) dystrophic rats, the cells survived in the subretinal space, where they maintained low levels of RPE65 expression and remained out of the cell cycle. The HESC-RPE cells responded to the in vivo environment by downregulating Pax6, while maintaining expression of other markers. The presence of rhodopsin-positive material within grafted HESC-RPE indicates that in the future, homogenous transplants of this cell type may be capable of supporting visual function following retinal dystrophy.

  16. Overexpression of miR-183/-96/-182 triggers neuronal cell fate in Human Retinal Pigment Epithelial (hRPE) cells in culture.

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    Davari, Maliheh; Soheili, Zahra-Soheila; Samiei, Shahram; Sharifi, Zohreh; Pirmardan, Ehsan Ranaei

    2017-01-29

    miR-183 cluster, composed of miR-183/-96/-182 genes, is highly expressed in the adult retina, particularly in photoreceptors. It involves in development, maturation and normal function of neuroretina. Ectopic overexpression of miR-183/-96/-182 genes was performed to assess reprogramming of hRPE cells. They were amplified from genomic DNA and cloned independently or in tandem configuration into pAAV.MCS vector. hRPE cells were then transfected with the recombinant constructs. Real-Time PCR was performed to measure the expression levels of miR-183/-96/-182 and that of several retina-specific neuronal genes such as OTX2, NRL, PDC and DCT. The transfected cells also were immunocytochemically examined for retina-specific neuronal markers, including Rhodopsin, red opsin, CRX, Thy1, CD73, recoverin and PKCα, to determine the cellular fate of the transfected hRPE cells. Data showed that upon miR-183/-96/-182 overexpression in hRPE cultures, the expression of neuronal genes including OTX2, NRL, PDC and DCT was also upregulated. Moreover, miR-183 cluster-treated hRPE cells were immunoreactive for neuronal markers such as Rhodopsin, red opsin, CRX and Thy1. Both transcriptional and translational upregulation of neuronal genes in miR-183 cluster-treated hRPE cells suggests that in vitro overexpression of miR-183 cluster could trigger reprogramming of hRPE cells to retinal neuron fate. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Cadherins in the retinal pigment epithelium (RPE revisited: P-cadherin is the highly dominant cadherin expressed in human and mouse RPE in vivo.

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    Xue Yang

    Full Text Available The retinal pigment epithelium (RPE supports the health and function of retinal photoreceptors and is essential for normal vision. RPE cells are post-mitotic, terminally differentiated, and polarized epithelial cells. In pathological conditions, however, they lose their epithelial integrity, become dysfunctional, even dedifferentiate, and ultimately die. The integrity of epithelial cells is maintained, in part, by adherens junctions, which are composed of cadherin homodimers and p120-, β-, and α-catenins linking to actin filaments. While E-cadherin is the major cadherin for forming the epithelial phenotype in most epithelial cell types, it has been reported that cadherin expression in RPE cells is different from other epithelial cells based on results with cultured RPE cells. In this study, we revisited the expression of cadherins in the RPE to clarify their relative contribution by measuring the absolute quantity of cDNAs produced from mRNAs of three classical cadherins (E-, N-, and P-cadherins in the RPE in vivo. We found that P-cadherin (CDH3 is highly dominant in both mouse and human RPE in situ. The degree of dominance of P-cadherin is surprisingly large, with mouse Cdh3 and human CDH3 accounting for 82-85% and 92-93% of the total of the three cadherin mRNAs, respectively. We confirmed the expression of P-cadherin protein at the cell-cell border of mouse RPE in situ by immunofluorescence. Furthermore, we found that oxidative stress induces dissociation of P-cadherin and β-catenin from the cell membrane and subsequent translocation of β-catenin into the nucleus, resulting in activation of the canonical Wnt/β-catenin pathway. This is the first report of absolute comparison of the expression of three cadherins in the RPE, and the results suggest that the physiological role of P-cadherin in the RPE needs to be reevaluated.

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

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    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.

  19. Proteasome inhibitors activate autophagy involving inhibition of PI3K-Akt-mTOR pathway as an anti-oxidation defense in human RPE cells.

    Directory of Open Access Journals (Sweden)

    Bingrong Tang

    Full Text Available The two major intracellular protein degradation systems, the ubiquitin-proteasome system (UPS and autophagy, work collaboratively in many biological processes including development, apoptosis, aging, and countering oxidative injuries. We report here that, in human retinal pigment epithelial cells (RPE, ARPE-19 cells, proteasome inhibitors, clasto-lactacystinβ-lactone (LA or epoxomicin (Epo, at non-lethal doses, increased the protein levels of autophagy-specific genes Atg5 and Atg7 and enhanced the conversion of microtubule-associated protein light chain (LC3 from LC3-I to its lipidative form, LC3-II, which was enhanced by co-addition of the saturated concentration of Bafilomycin A1 (Baf. Detection of co-localization for LC3 staining and labeled-lysosome further confirmed autophagic flux induced by LA or Epo. LA or Epo reduced the phosphorylation of the protein kinase B (Akt, a downstream target of phosphatidylinositol-3-kinases (PI3K, and mammalian target of rapamycin (mTOR in ARPE-19 cells; by contrast, the induced changes of autophagy substrate, p62, showed biphasic pattern. The autophagy inhibitor, Baf, attenuated the reduction in oxidative injury conferred by treatment with low doses of LA and Epo in ARPE-19 cells exposed to menadione (VK3 or 4-hydroxynonenal (4-HNE. Knockdown of Atg7 with siRNA in ARPE-19 cells reduced the protective effects of LA or Epo against VK3. Overall, our results suggest that treatment with low levels of proteasome inhibitors confers resistance to oxidative injury by a pathway involving inhibition of the PI3K-Akt-mTOR pathway and activation of autophagy.

  20. Odorant Receptor 51E2 Agonist β-ionone Regulates RPE Cell Migration and Proliferation

    Directory of Open Access Journals (Sweden)

    Nikolina Jovancevic

    2017-11-01

    Full Text Available The odorant receptor 51E2 (OR51E2, which is well-characterized in prostate cancer cells and epidermal pigment cells, was identified for the first time as the most highly expressed OR in human fetal and adult retinal pigment epithelial (RPE cells. Immunofluorescence staining and Western blot analysis revealed OR51E2 localization throughout the cytosol and in the plasma membrane. Additionally, immunohistochemical staining of diverse layers of the eye showed that the expression of OR51E2 is restricted to the pigment cells of the RPE and choroid. The results of Ca2+-imaging experiments demonstrate that activation of OR51E2 triggers a Ca2+ dependent signal pathway in RPE cells. Downstream signaling of OR51E2 involves the activation of adenylyl cyclase, ERK1/2 and AKT. The activity of these protein kinases likely accounts for the demonstrated increase in the migration and proliferation of RPE cells upon stimulation with the OR51E2 ligand β-ionone. These findings suggest that OR51E2 is involved in the regulation of RPE cell growth. Thus, OR51E2 represents a potential target for the treatment of proliferative disorders.

  1. Probable Chemical Hypoxia Effects on Progress of CNV Through Induction of Promoter CpG Demethylation and Overexpression of IL17RC in Human RPE Cells.

    Science.gov (United States)

    Alivand, Mohammad Reza; Sabouni, Farzaneh; Soheili, Zahra-Soheila

    2016-09-01

    To survey the changes of promoter CpG methylation status and mRNA expression of IL17RC (interleukin 17 receptor C) gene in retinal pigment epithelium (RPE) cells under chemical hypoxia condition for choroidal neovascularization (CNV) modeling in vitro. RPE cells were cultured in both untreated as a control group and treated by cobalt chloride media as a hypoxia group for various concentrations (100-150μM) and times (24-36 hrs.) To confirm chemical hypoxia condition, mRNA expression of HIF (Hypoxia Inducible Factor) -1α, -2α, and Vascular Endothelial Growth Factor (VEGF) was compared between two groups by Real-time PCR. Also, in normoxia and hypoxia conditions, IL17RC expression changes and promoter CpG methylation status were evaluated by Real-time PCR and methylation-specific PCR (MSP) techniques, respectively. Overexpression of HIF-1α, HIF-2α, and VEGF was significant in hypoxia versus normoxia conditions. Our data showed overexpression of IL17RC (2.1- to 6.3-fold) and decreasing of its promoter methylation in comparison with hypoxia and normoxia conditions. It was found that there are significant association between promoter methylation status and expression of IL17RC in chemical hypoxia condition. Therefore, methylation of IL17RC could play as a marker in CNV and degeneration of RPE cells in vitro. Additionally, HIF-α and methylation phenomena may be considered as critical targets for blocking in angiogenesis of age-related degeneration in future studies.

  2. The anterior lens capsule used as support material in RPE cell-transplantation

    DEFF Research Database (Denmark)

    Nicolini, J; Kiilgaard, Jens Folke; Wiencke, A K

    2000-01-01

    To investigate the use of an ocular basement membrane as support material for transplanted porcine RPE cells.......To investigate the use of an ocular basement membrane as support material for transplanted porcine RPE cells....

  3. RPE cell surface proteins in normal and dystrophic rats

    International Nuclear Information System (INIS)

    Clark, V.M.; Hall, M.O.

    1986-01-01

    Membrane-bound proteins in plasma membrane enriched fractions from cultured rat RPE were analyzed by two-dimensional gel electrophoresis. Membrane proteins were characterized on three increasingly specific levels. Total protein was visualized by silver staining. A maximum of 102 separate proteins were counted in silver-stained gels. Glycoproteins were labeled with 3H-glucosamine or 3H-fucose and detected by autoradiography. Thirty-eight fucose-labeled and 61-71 glucosamine-labeled proteins were identified. All of the fucose-labeled proteins were labeled with glucosamine-derived radioactivity. Proteins exposed at the cell surface were labeled by lactoperoxidase-catalyzed radioiodination prior to preparation of membranes for two-dimensional analysis. Forty separate 125I-labeled surface proteins were resolved by two-dimensional electrophoresis/autoradiography. Comparison with the glycoprotein map showed that a number of these surface labeled proteins were glycoproteins. Two-dimensional maps of total protein, fucose-labeled, and glucosamine-labeled glycoproteins, and 125I-labeled surface proteins of membranes from dystrophic (RCS rdy-p+) and normal (Long Evans or RCS rdy+p+) RPE were compared. No differences in the total protein or surface-labeled proteins were observed. However, the results suggest that a 183K glycoprotein is more heavily glycosylated with glucosamine and fucose in normal RPE membranes as compared to membranes from dystrophic RPE

  4. Retinal pigment epithelial cells secrete neurotrophic factors and synthesize dopamine: possible contribution to therapeutic effects of RPE cell transplantation in Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Gu Qing

    2009-06-01

    Full Text Available Abstract Background New strategies for the treatment of Parkinson's disease (PD are shifted from dopamine (DA replacement to regeneration or restoration of the nigro-striatal system. A cell therapy using human retinal pigment epithelial (RPE cells as substitution for degenerated dopaminergic (DAergic neurons has been developed and showed promising prospect in clinical treatment of PD, but the exact mechanism underlying this therapy is not fully elucidated. In the present study, we investigated whether the beneficial effects of this therapy are related to the trophic properties of RPE cells and their ability to synthesize DA. Methods We evaluated the protective effects of conditioned medium (CM from cultured RPE cells on the DAergic cells against 6-hydroxydopamine (6-OHDA- and rotenone-induced neurotoxicity and determined the levels of glial cell derived neurotrophic factor (GDNF and brain derived neurotrophic factor (BDNF released by RPE cells. We also measured the DA synthesis and release. Finally we transplanted microcarriers-RPE cells into 6-OHDA lesioned rats and observed the improvement in apomorphine-induced rotations (AIR. Results We report here: (1 CM from RPE cells can secret trophic factors GDNF and BDNF, and protect DAergic neurons against the 6-OHDA- and rotenone-induced cell injury; (2 cultured RPE cells express L-dopa decarboxylase (DDC and synthesize DA; (3 RPE cells attached to microcarriers can survive in the host striatum and improve the AIR in 6-OHDA-lesioned animal model of PD; (4 GDNF and BDNF levels are found significantly higher in the RPE cell-grafted tissues. Conclusion These findings indicate the RPE cells have the ability to secret GDNF and BDNF, and synthesize DA, which probably contribute to the therapeutic effects of RPE cell transplantation in PD.

  5. A2E Suppresses Regulatory Function of RPE Cells in Th1 Cell Differentiation Via Production of IL-1β and Inhibition of PGE2.

    Science.gov (United States)

    Shi, Qian; Wang, Qiu; Li, Jing; Zhou, Xiaohui; Fan, Huimin; Wang, Fenghua; Liu, Haiyun; Sun, Xiangjun; Sun, Xiaodong

    2015-12-01

    Inflammatory status of RPE cells induced by A2E is essential in the development of AMD. Recent research indicated T-cell immunity was involved in the pathological progression of AMD. This study was designed to investigate how A2E suppresses immunoregulatory function of RPE cells in T-cell immunity in vitro. Mouse RPE cells or human ARPE19 cells were stimulated with A2E, and co-cultured with naïve T cells under Th1, Th2, Th17, and regulatory T cell (Treg) polarization conditions. The intracellular cytokines or transcript factors of the induced T-cells subset were detected with flow cytometer and qRT-PCR. The ROS levels were detected, and the factors and possible pathways involved in the A2E-laden RPE cells were analyzed through neutralization antibody of IL-1β and inhibitors of related pathways. The A2E reduced regulatory function of RPE cells in Treg differentiation. The A2E-laden RPE cells promoted polarization of Th1 cells in vitro, but not Th2 or Th17 differentiation. The A2E induced RPE cells to release inflammatory cytokines and ROS, but PGE2 production was inhibited. Through neutralization of IL-1β or inhibition of COX2-PGE2 pathways, A2E-laden RPE cells expressed reduced effect in inducing Th1 cells. The A2E inhibited regulatory function of RPE cells in suppressing Th1 cell immunity in vitro through production of IL-1β and inhibition of PGE2. Our data indicate that A2E could suppress immunoregulatory function of RPE cells and adaptive immunity might play a role in the immune pathogenesis of AMD.

  6. Effects of aflibercept on primary RPE cells: toxicity, wound healing, uptake and phagocytosis.

    Science.gov (United States)

    Klettner, Alexa; Tahmaz, Nihat; Dithmer, Michaela; Richert, Elisabeth; Roider, Johann

    2014-10-01

    Anti-VEGF treatment is the therapy of choice in age-related macular degeneration, and is also applied in diabetic macular oedema or retinal vein occlusion. Recently, the fusion protein, aflibercept, has been approved for therapeutic use. In this study, we investigate the effects of aflibercept on primary RPE cells. Primary RPE cells were prepared from freshly slaughtered pigs' eyes. The impact of aflibercept on cell viability was investigated with MTT and trypan blue exclusion assay. The influence of aflibercept on wound healing was assessed with a scratch assay. Intracellular uptake of aflibercept was investigated in immunohistochemistry and its influence on phagocytosis with a phagocytosis assay using opsonised latex beads. Aflibercept displays no cytotoxicity on RPE cells but impairs its wound healing ability. It is taken up into RPE cells and can be intracellularly detected for at least 7 days. Intracellular aflibercept impairs the phagocytic capacity of RPE cells. Aflibercept interferes with the physiology of RPE cells, as it is taken up into RPE cells, which is accompanied by a reduction of the phagocytic ability. Additionally, it impairs the wound healing capacity of RPE cells. These effects on the physiology of RPE cells may indicate possible side effects. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  7. Transcriptomic analysis across nasal, temporal, and macular regions of human neural retina and RPE/choroid by RNA-Seq

    Science.gov (United States)

    Whitmore, S. Scott; Wagner, Alex H.; DeLuca, Adam P.; Drack, Arlene V.; Stone, Edwin M.; Tucker, Budd A.; Zeng, Shemin; Braun, Terry A.; Mullins, Robert F.; Scheetz, Todd E.

    2014-01-01

    Proper spatial differentiation of retinal cell types is necessary for normal human vision. Many retinal diseases, such as Best disease and male germ cell associated kinase (MAK)-associated retinitis pigmentosa, preferentially affect distinct topographic regions of the retina. While much is known about the distribution of cell-types in the retina, the distribution of molecular components across the posterior pole of the eye has not been well-studied. To investigate regional difference in molecular composition of ocular tissues, we assessed differential gene expression across the temporal, macular, and nasal retina and retinal pigment epithelium (RPE)/choroid of human eyes using RNA-Seq. RNA from temporal, macular, and nasal retina and RPE/choroid from four human donor eyes was extracted, poly-A selected, fragmented, and sequenced as 100 bp read pairs. Digital read files were mapped to the human genome and analyzed for differential expression using the Tuxedo software suite. Retina and RPE/choroid samples were clearly distinguishable at the transcriptome level. Numerous transcription factors were differentially expressed between regions of the retina and RPE/choroid. Photoreceptor-specific genes were enriched in the peripheral samples, while ganglion cell and amacrine cell genes were enriched in the macula. Within the RPE/choroid, RPE-specific genes were upregulated at the periphery while endothelium associated genes were upregulated in the macula. Consistent with previous studies, BEST1 expression was lower in macular than extramacular regions. The MAK gene was expressed at lower levels in macula than in extramacular regions, but did not exhibit a significant difference between nasal and temporal retina. The regional molecular distinction is greatest between macula and periphery and decreases between different peripheral regions within a tissue. Datasets such as these can be used to prioritize candidate genes for possible involvement in retinal diseases with

  8. Transcriptomic analysis across nasal, temporal, and macular regions of human neural retina and RPE/choroid by RNA-Seq.

    Science.gov (United States)

    Whitmore, S Scott; Wagner, Alex H; DeLuca, Adam P; Drack, Arlene V; Stone, Edwin M; Tucker, Budd A; Zeng, Shemin; Braun, Terry A; Mullins, Robert F; Scheetz, Todd E

    2014-12-01

    Proper spatial differentiation of retinal cell types is necessary for normal human vision. Many retinal diseases, such as Best disease and male germ cell associated kinase (MAK)-associated retinitis pigmentosa, preferentially affect distinct topographic regions of the retina. While much is known about the distribution of cell types in the retina, the distribution of molecular components across the posterior pole of the eye has not been well-studied. To investigate regional difference in molecular composition of ocular tissues, we assessed differential gene expression across the temporal, macular, and nasal retina and retinal pigment epithelium (RPE)/choroid of human eyes using RNA-Seq. RNA from temporal, macular, and nasal retina and RPE/choroid from four human donor eyes was extracted, poly-A selected, fragmented, and sequenced as 100 bp read pairs. Digital read files were mapped to the human genome and analyzed for differential expression using the Tuxedo software suite. Retina and RPE/choroid samples were clearly distinguishable at the transcriptome level. Numerous transcription factors were differentially expressed between regions of the retina and RPE/choroid. Photoreceptor-specific genes were enriched in the peripheral samples, while ganglion cell and amacrine cell genes were enriched in the macula. Within the RPE/choroid, RPE-specific genes were upregulated at the periphery while endothelium associated genes were upregulated in the macula. Consistent with previous studies, BEST1 expression was lower in macular than extramacular regions. The MAK gene was expressed at lower levels in macula than in extramacular regions, but did not exhibit a significant difference between nasal and temporal retina. The regional molecular distinction is greatest between macula and periphery and decreases between different peripheral regions within a tissue. Datasets such as these can be used to prioritize candidate genes for possible involvement in retinal diseases with

  9. 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.

  10. Protective Effect of Combined Caffeic Acid Phenethyl Ester and Bevacizumab Against Hydrogen Peroxide-Induced Oxidative Stress in Human RPE Cells.

    Science.gov (United States)

    Dinc, Erdem; Ayaz, Lokman; Kurt, Akif Hakan

    2017-12-01

    This study aimed to evaluate the protective effects of caffeic acid phenethyl ester (CAPE) and combined CAPE-bevacizumab against oxidative stress induced by hydrogen peroxide (H 2 O 2 ) in human retinal pigment epithelium. ARPE-19 cells were pretreated with 5, 10, and 30 μM CAPE alone and in combination with bevacizumab for 3 h, then exposed to H 2 O 2 for 16 h. Cell viability was evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Vascular endothelial growth factor (VEGF) protein levels in the medium were measured using a human VEGF ELISA kit. Total antioxidant status (TAS) and total oxidant status (TOS) were measured in ARPE-19 cells using the test kit from Rel Assay. Expression levels of VEGF, Bax, Bcl-2, cytochrome c, apoptotic protease activating factor-1 (apaf-1), and caspase-3 were determined using reverse transcription polymerase chain reaction. Pretreatment of ARPE-19 cells with 30 μM CAPE and combined CAPE-bevacizumab reduced H 2 O 2 mediated cell death. H 2 O 2 -induced oxidative stress increased TOS and VEGF production, which was significantly inhibited by CAPE and the CAPE-bevacizumab combination. VEGF, Bax, cytochrome c, apaf-1, and caspase-3 gene expressions were significantly decreased in cells pretreated with 5, 10, and 30 μM CAPE and combined CAPE-bevacizumab compared to the H 2 O 2 group. In addition, Bcl-2 expression was significantly increased in both the CAPE and CAPE-bevacizumab combination groups compared to the H 2 O 2 group. CAPE has a protective effect on ARPE-19 cells against oxidative stress, and VEGF protein level and expression can be decreased by incubation with different concentrations of CAPE. These results demonstrate that CAPE suppresses the mitochondria-mediated apoptosis in ARPE-19 cells under oxidative stress. In addition, the use of CAPE in combination with bevacizumab has an additive effect.

  11. Bcl-2, Bax, and c-Fos expression correlates to RPE cell apoptosis induced by UV-light and daunorubicin

    DEFF Research Database (Denmark)

    Liang, Y G; Jorgensen, A G; Kaestel, C G

    2000-01-01

    PURPOSE. The aim of this study was to determine the role of Bcl-2, Bcl-X L, Bax, and c-Fos in regulation of apoptosis, induced by ultraviolet-light A (UV-A) and daunorubicin (DNR), in retinal pigment epithelium (RPE) cells grown on bovine extracellular matrix (ECM)-coated or uncoated plastic dishes....... METHODS. Apoptosis in confluent RPE cells cultured on ECM-coated or uncoated dishes was induced by UV-A or DNR. Apoptosis was detected by 7-amino-actinomycin D labeling followed by flow cytometry and by terminal deoxy-transferase mediated X-dUTP nick end labeling (TUNEL). Cellular expression of Bcl-2, Bcl......-X L, Bax, and c-Fos was determined by the use of antibodies and flow cytometry, Western blot analysis, and immunocytochemical staining. RESULTS. Both UV-A and DNR induce apoptosis in human RPE cells in vitro. Human fetal RPE cells grown on ECM-coated dishes were significantly more resistant to UV...

  12. Cystic fibrosis transmembrane conductance regulator contributes to reacidification of alkalinized lysosomes in RPE cells.

    Science.gov (United States)

    Liu, Ji; Lu, Wennan; Guha, Sonia; Baltazar, Gabriel C; Coffey, Erin E; Laties, Alan M; Rubenstein, Ronald C; Reenstra, William W; Mitchell, Claire H

    2012-07-15

    The role of the cystic fibrosis transmembrane conductance regulator (CFTR) in lysosomal acidification has been difficult to determine. We demonstrate here that CFTR contributes more to the reacidification of lysosomes from an elevated pH than to baseline pH maintenance. Lysosomal alkalinization is increasingly recognized as a factor in diseases of accumulation, and we previously showed that cAMP reacidified alkalinized lysosomes in retinal pigmented epithelial (RPE) cells. As the influx of anions to electrically balance proton accumulation may enhance lysosomal acidification, the contribution of the cAMP-activated anion channel CFTR to lysosomal reacidification was probed. The antagonist CFTR(inh)-172 had little effect on baseline levels of lysosomal pH in cultured human RPE cells but substantially reduced the reacidification of compromised lysosomes by cAMP. Likewise, CFTR activators had a bigger impact on cells whose lysosomes had been alkalinized. Knockdown of CFTR with small interfering RNA had a larger effect on alkalinized lysosomes than on baseline levels. Inhibition of CFTR in isolated lysosomes altered pH. While CFTR and Lamp1 were colocalized, treatment with cAMP did not increase targeting of CFTR to the lysosome. The inhibition of CFTR slowed lysosomal degradation of photoreceptor outer segments while activation of CFTR enhanced their clearance from compromised lysosomes. Activation of CFTR acidified RPE lysosomes from the ABCA4(-/-) mouse model of recessive Stargardt's disease, whose lysosomes are considerably alkalinized. In summary, CFTR contributes more to reducing lysosomal pH from alkalinized levels than to maintaining baseline pH. Treatment to activate CFTR may thus be of benefit in disorders of accumulation associated with lysosomal alkalinization.

  13. TNF-α decreases VEGF secretion in highly polarized RPE cells but increases it in non-polarized RPE cells related to crosstalk between JNK and NF-κB pathways.

    Directory of Open Access Journals (Sweden)

    Hiroto Terasaki

    Full Text Available Asymmetrical secretion of vascular endothelial growth factor (VEGF by retinal pigment epithelial (RPE cells in situ is critical for maintaining the homeostasis of the retina and choroid. VEGF is also involved in the development and progression of age-related macular degeneration (AMD. We studied the effect of tumor necrosis factor-α (TNF-α on the secretion of VEGF in polarized and non-polarized RPE cells (P-RPE cells and N-RPE cells, respectively in culture and in situ in rats. A subretinal injection of TNF-α caused a decrease in VEGF expression and choroidal atrophy. Porcine RPE cells were seeded on Transwell™ filters, and their maturation and polarization were confirmed by the asymmetrical VEGF secretion and trans electrical resistance. Exposure to TNF-α decreased the VEGF secretion in P-RPE cells but increased it in N-RPE cells in culture. TNF-α inactivated JNK in P-RPE cells but activated it in N-RPE cells, and TNF-α activated NF-κB in P-RPE cells but not in N-RPE cells. Inhibition of NF-κB activated JNK in both types of RPE cells indicating crosstalk between JNK and NF-κB. TNF-α induced the inhibitory effects of NF-κB on JNK in P-RPE cells because NF-κB is continuously inactivated. In N-RPE cells, however, it was not evident because NF-κB was already activated. The basic activation pattern of JNK and NF-κB and their crosstalk led to opposing responses of RPE cells to TNF-α. These results suggest that VEGF secretion under inflammatory conditions depends on cellular polarization, and the TNF-α-induced VEGF down-regulation may result in choroidal atrophy in polarized physiological RPE cells. TNF-α-induced VEGF up-regulation may cause neovascularization by non-polarized or non-physiological RPE cells.

  14. Oxidative Stress Induces Senescence in Cultured RPE Cells.

    Science.gov (United States)

    Aryan, Nona; Betts-Obregon, Brandi S; Perry, George; Tsin, Andrew T

    2016-01-01

    The aim of this research is to determine whether oxidative stress induces cellular senescence in human retinal pigment epithelial cells. Cultured ARPE19 cells were subjected to different concentrations of hydrogen peroxide to induce oxidative stress. Cells were seeded into 24-well plates with hydrogen peroxide added to cell medium and incubated at 37°C + 5% CO2 for a 90-minute period [at 0, 300, 400 and 800 micromolar (MCM) hydrogen peroxide]. The number of viable ARPE19 cells were recorded using the Trypan Blue Dye Exclusion Method and cell senescence was measured by positive staining for senescence-associated beta-galactosidase (SA-beta-Gal) protein. Without hydrogen peroxide treatment, the number of viable ARPE19 cells increased significantly from 50,000 cells/well to 197,000 within 72 hours. Treatment with hydrogen peroxide reduced this level of cell proliferation significantly (to 52,167 cells at 400 MCM; to 49,263 cells at 800 MCM). Meanwhile, cells with a high level of positive senescence-indicator SA-Beta-Gal-positive staining was induced by hydrogen peroxide treatment (from a baseline level of 12% to 80% at 400 MCM and at 800 MCM). Our data suggests that oxidative stress from hydrogen peroxide treatment inhibited ARPE19 cell proliferation and induced cellular senescence.

  15. Subretinal posterior pole injury induces selective proliferation of RPE cells in the periphery in in vivo studies in pigs

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Prause, Jan U; Prause, Michala

    2007-01-01

    PURPOSE: To study topographical differences in porcine retinal pigment epithelial (RPE) cell proliferation (1) in vivo, after experimental central surgical subretinal injury, and (2) in vitro. METHODS: Domestic pigs underwent either experimental RPE debridement (n = 5), subretinal amniotic membrane...... cells. This observation was true of both types of experimental surgery performed. In vitro, RPE isolates from the pre-equatorial region consistently yielded higher cell densities than did RPE cell isolates from more central parts of the epithelium. This was apparent through the three first passages...

  16. Canine and human visual cortex intact and responsive despite early retinal blindness from RPE65 mutation.

    Directory of Open Access Journals (Sweden)

    Geoffrey K Aguirre

    2007-06-01

    Full Text Available RPE65 is an essential molecule in the retinoid-visual cycle, and RPE65 gene mutations cause the congenital human blindness known as Leber congenital amaurosis (LCA. Somatic gene therapy delivered to the retina of blind dogs with an RPE65 mutation dramatically restores retinal physiology and has sparked international interest in human treatment trials for this incurable disease. An unanswered question is how the visual cortex responds after prolonged sensory deprivation from retinal dysfunction. We therefore studied the cortex of RPE65-mutant dogs before and after retinal gene therapy. Then, we inquired whether there is visual pathway integrity and responsivity in adult humans with LCA due to RPE65 mutations (RPE65-LCA.RPE65-mutant dogs were studied with fMRI. Prior to therapy, retinal and subcortical responses to light were markedly diminished, and there were minimal cortical responses within the primary visual areas of the lateral gyrus (activation amplitude mean +/- standard deviation [SD] = 0.07% +/- 0.06% and volume = 1.3 +/- 0.6 cm(3. Following therapy, retinal and subcortical response restoration was accompanied by increased amplitude (0.18% +/- 0.06% and volume (8.2 +/- 0.8 cm(3 of activation within the lateral gyrus (p < 0.005 for both. Cortical recovery occurred rapidly (within a month of treatment and was persistent (as long as 2.5 y after treatment. Recovery was present even when treatment was provided as late as 1-4 y of age. Human RPE65-LCA patients (ages 18-23 y were studied with structural magnetic resonance imaging. Optic nerve diameter (3.2 +/- 0.5 mm was within the normal range (3.2 +/- 0.3 mm, and occipital cortical white matter density as judged by voxel-based morphometry was slightly but significantly altered (1.3 SD below control average, p = 0.005. Functional magnetic resonance imaging in human RPE65-LCA patients revealed cortical responses with a markedly diminished activation volume (8.8 +/- 1.2 cm(3 compared to controls

  17. Zeaxanthin Inhibits Hypoxia-Induced VEGF Secretion by RPE Cells through Decreased Protein Levels of Hypoxia-Inducible Factors-1α

    Directory of Open Access Journals (Sweden)

    Richard Rosen

    2015-01-01

    Full Text Available Hypoxia is the most important stimulus leading to upregulation of VEGF in the retina and this is caused by accumulation of hypoxia-inducible factors-1α (HIF-1α protein. The effects of zeaxanthin, a natural phytochemical, on the VEGF and HIF-1α expression in the primary culture of human retinal pigment epithelial (RPE cells were studied. An in vitro RPE cell hypoxia model was established by placing cells under 1% oxygen pressure or by adding cobalt chloride (CoCl2 to the culture medium. RPE cells and conditioned media were collected from cultures treated with and without zeaxanthin under normoxic and hypoxic conditions. VEGF and HIF-1α protein and RNA levels were measured by ELISA kits and RT-PCR, respectively. Hypoxia caused a significant increase of VEGF expression and accumulation of HIF-1α in RPE cells. Zeaxanthin at 50–150 μM significantly inhibited the expression of VEGF and accumulation of HIF-1α protein caused by hypoxia but did not affect expression of VEGF and HIF-1α under normoxic conditions. This is the first report on the effect of zeaxanthin on VEGF and HIF-1α levels in cultured RPE cells and suggests that zeaxanthin may have potential value in the prevention and treatment of various retinal diseases associated with vascular leakage and neovascularization.

  18. Effect of SOCS1 overexpression on RPE cell activation by proinflammatory cytokines.

    Science.gov (United States)

    Bazewicz, Magdalena; Draganova, Dafina; Makhoul, Maya; Chtarto, Abdel; Elmaleh, Valerie; Tenenbaum, Liliane; Caspers, Laure; Bruyns, Catherine; Willermain, François

    2016-09-06

    The purpose of this study was to investigate the in vitro effect of Suppressor Of Cytokine Signaling 1 (SOCS1) overexpression in retinal pigment epithelium (RPE) cells on their activation by pro-inflammatory cytokines IFNγ, TNFα and IL-17. Retinal pigment epithelium cells (ARPE-19) were stably transfected with the control plasmid pIRES2-AcGFP1 or the plasmid pSOCS1-IRES2-AcGFP1. They were stimulated by IFNγ (150ng/ml), TNFα (30ng/ml) or IL-17 (100ng/ml). The levels of SOCS1 mRNA were measured by real-time PCR. Signal Transducer and Activator of Transcription 1 (STAT1) phosphorylation and IκBα expression were analysed by western Blot (WB). IL-8 secretion was analysed by ELISA and expression of MHCII molecules and ICAM-1/CD54 by flow cytometry. Our data show that SOCS1 mRNA overexpression in RPE cells prevents IFNγ-induced SOCS1 mRNA increase and IFNγ-mediated STAT1 phosphorylation. Moreover, SOCS1 overexpression in RPE cells inhibits IFNγ-induced decrease of IL-8 secretion and prevents IFNγ-induced MHC II and ICAM1/CD54 upregulation. However, SOCS1 overexpression does not affect TNFα-induced IκBα degradation nor block TNFα-induced or IL-17-induced IL-8 secretion. On the contrary, IL-17-induced secretion is increased by SOCS1 overexpression. In conclusion, SOCS1 overexpression in RPE cells inhibits some IFNγ-mediated responses that lead to uveitis development. This notion raises the possibility that SOCS1 overexpression could be a novel target for treating non-infectious uveitis. However, some proinflammatory effects of TNFα and IL-17 stimulation on RPE are not blocked by SOCS1 overexpression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Repressed SIRT1/PGC-1α pathway and mitochondrial disintegration in iPSC-derived RPE disease model of age-related macular degeneration.

    Science.gov (United States)

    Golestaneh, Nady; Chu, Yi; Cheng, Shuk Kei; Cao, Hong; Poliakov, Eugenia; Berinstein, Daniel M

    2016-12-20

    Study of age related macular degeneration (AMD) has been hampered by lack of human models that represent the complexity of the disease. Here we have developed a human in vitro disease model of AMD to investigate the underlying AMD disease mechanisms. Generation of iPSCs from retinal pigment epithelium (RPE) of AMD donors, age-matched normal donors, skin fibroblasts of a dry AMD patient, and differentiation of iPSCs into RPE (AMD RPE-iPSC-RPE, normal RPE-iPSC-RPE and AMD Skin-iPSC-RPE, respectively). Immunostaining, cell viability assay and reactive oxygen species (ROS) production under oxidative stress conditions, electron microscopy (EM) imaging, ATP production and glycogen concentration assays, quantitative real time PCR, western blot, karyotyping. The AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE present functional impairment and exhibit distinct disease phenotypes compared to RPE-iPSC-RPE generated from normal donors (Normal RPE-iPSC-RPE). The AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE show increased susceptibility to oxidative stress and produced higher levels of reactive oxygen species (ROS) under stress in accordance with recent reports. The susceptibility to oxidative stress-induced cell death in AMD RPE-iPSC-RPE and Skin-iPSC-RPE was consistent with inability of the AMD RPE-iPSC-RPE and Skin-iPSC-RPE to increase SOD2 expression under oxidative stress. Phenotypic analysis revealed disintegrated mitochondria, accumulation of autophagosomes and lipid droplets in AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE. Mitochondrial activity was significantly lower in AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE compared to normal cells and glycogen concentration was significantly increased in the diseased cells. Furthermore, Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), a regulator of mitochondrial biogenesis and function was repressed, and lower expression levels of NAD-dependent deacetylase sirtuin1 (SIRT1) were found in AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE

  20. Galectin-3 Induces Clustering of CD147 and Integrin-β1 Transmembrane Glycoprotein Receptors on the RPE Cell Surface

    Science.gov (United States)

    Priglinger, Claudia S.; Szober, Christoph M.; Priglinger, Siegfried G.; Merl, Juliane; Euler, Kerstin N.; Kernt, Marcus; Gondi, Gabor; Behler, Jennifer; Geerlof, Arie; Kampik, Anselm; Ueffing, Marius; Hauck, Stefanie M.

    2013-01-01

    Proliferative vitreoretinopathy (PVR) is a blinding disease frequently occurring after retinal detachment surgery. Adhesion, migration and matrix remodeling of dedifferentiated retinal pigment epithelial (RPE) cells characterize the onset of the disease. Treatment options are still restrained and identification of factors responsible for the abnormal behavior of the RPE cells will facilitate the development of novel therapeutics. Galectin-3, a carbohydrate-binding protein, was previously found to inhibit attachment and spreading of retinal pigment epithelial cells, and thus bares the potential to counteract PVR-associated cellular events. However, the identities of the corresponding cell surface glycoprotein receptor proteins on RPE cells are not known. Here we characterize RPE-specific Gal-3 containing glycoprotein complexes using a proteomic approach. Integrin-β1, integrin-α3 and CD147/EMMPRIN, a transmembrane glycoprotein implicated in regulating matrix metalloproteinase induction, were identified as potential Gal-3 interactors on RPE cell surfaces. In reciprocal immunoprecipitation experiments we confirmed that Gal-3 associated with CD147 and integrin-β1, but not with integrin-α3. Additionally, association of Gal-3 with CD147 and integrin-β1 was observed in co-localization analyses, while integrin-α3 only partially co-localized with Gal-3. Blocking of CD147 and integrin-β1 on RPE cell surfaces inhibited binding of Gal-3, whereas blocking of integrin-α3 failed to do so, suggesting that integrin-α3 is rather an indirect interactor. Importantly, Gal-3 binding promoted pronounced clustering and co-localization of CD147 and integrin-β1, with only partial association of integrin-α3. Finally, we show that RPE derived CD147 and integrin-β1, but not integrin-α3, carry predominantly β-1,6-N-actyl-D-glucosamine-branched glycans, which are high-affinity ligands for Gal-3. We conclude from these data that extracellular Gal-3 triggers clustering of CD147 and

  1. Galectin-3 induces clustering of CD147 and integrin-β1 transmembrane glycoprotein receptors on the RPE cell surface.

    Directory of Open Access Journals (Sweden)

    Claudia S Priglinger

    Full Text Available Proliferative vitreoretinopathy (PVR is a blinding disease frequently occurring after retinal detachment surgery. Adhesion, migration and matrix remodeling of dedifferentiated retinal pigment epithelial (RPE cells characterize the onset of the disease. Treatment options are still restrained and identification of factors responsible for the abnormal behavior of the RPE cells will facilitate the development of novel therapeutics. Galectin-3, a carbohydrate-binding protein, was previously found to inhibit attachment and spreading of retinal pigment epithelial cells, and thus bares the potential to counteract PVR-associated cellular events. However, the identities of the corresponding cell surface glycoprotein receptor proteins on RPE cells are not known. Here we characterize RPE-specific Gal-3 containing glycoprotein complexes using a proteomic approach. Integrin-β1, integrin-α3 and CD147/EMMPRIN, a transmembrane glycoprotein implicated in regulating matrix metalloproteinase induction, were identified as potential Gal-3 interactors on RPE cell surfaces. In reciprocal immunoprecipitation experiments we confirmed that Gal-3 associated with CD147 and integrin-β1, but not with integrin-α3. Additionally, association of Gal-3 with CD147 and integrin-β1 was observed in co-localization analyses, while integrin-α3 only partially co-localized with Gal-3. Blocking of CD147 and integrin-β1 on RPE cell surfaces inhibited binding of Gal-3, whereas blocking of integrin-α3 failed to do so, suggesting that integrin-α3 is rather an indirect interactor. Importantly, Gal-3 binding promoted pronounced clustering and co-localization of CD147 and integrin-β1, with only partial association of integrin-α3. Finally, we show that RPE derived CD147 and integrin-β1, but not integrin-α3, carry predominantly β-1,6-N-actyl-D-glucosamine-branched glycans, which are high-affinity ligands for Gal-3. We conclude from these data that extracellular Gal-3 triggers

  2. Exogenous NAD(+) decreases oxidative stress and protects H2O2-treated RPE cells against necrotic death through the up-regulation of autophagy.

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

    2016-05-31

    Increased oxidative stress, which can lead to the retinal pigment epithelium (RPE) cell death by inducing ATP depletion and DNA repair, is believed to be a prominent pathology in age-related macular degeneration (AMD). In the present study, we showed that and 0.1 mM nicotinamide adenine dinucleotide (NAD(+)) administration significantly blocked RPE cell death induced by 300 μM H2O2. Further investigation showed that H2O2 resulted in increased intracellular ROS level, activation of PARP-1 and subsequently necrotic death of RPE cells. Exogenous NAD(+) administration significantly decreased intracellular and intranuclear ROS levels in H2O2-treated RPE cells. In addition, NAD(+) administration to H2O2-treated RPE cells inhibited the activation of PARP-1 and protected the RPE cells against necrotic death. Moreover, exogenous NAD(+) administration up-regulated autophagy in the H2O2-treated RPE cells. Inhibition of autophagy by LY294002 blocked the decrease of intracellular and intranuclear ROS level. Besides, inhibition of autophagy by LY294002 abolished the protection of exogenous NAD(+) against H2O2-induced cell necrotic death. Taken together, our findings indicate that that exogenous NAD(+) administration suppresses H2O2-induced oxidative stress and protects RPE cells against PARP-1 mediated necrotic death through the up-regulation of autophagy. The results suggest that exogenous NAD(+) administration might be potential value for the treatment of AMD.

  3. Exogenous NAD+ decreases oxidative stress and protects H2O2-treated RPE cells against necrotic death through the up-regulation of autophagy

    Science.gov (United States)

    Zhu, Ying; Zhao, Ke-ke; Tong, Yao; Zhou, Ya-li; Wang, Yi-xiao; Zhao, Pei-quan; Wang, Zhao-yang

    2016-01-01

    Increased oxidative stress, which can lead to the retinal pigment epithelium (RPE) cell death by inducing ATP depletion and DNA repair, is believed to be a prominent pathology in age-related macular degeneration (AMD). In the present study, we showed that and 0.1 mM nicotinamide adenine dinucleotide (NAD+) administration significantly blocked RPE cell death induced by 300 μM H2O2. Further investigation showed that H2O2 resulted in increased intracellular ROS level, activation of PARP-1 and subsequently necrotic death of RPE cells. Exogenous NAD+ administration significantly decreased intracellular and intranuclear ROS levels in H2O2-treated RPE cells. In addition, NAD+ administration to H2O2-treated RPE cells inhibited the activation of PARP-1 and protected the RPE cells against necrotic death. Moreover, exogenous NAD+ administration up-regulated autophagy in the H2O2-treated RPE cells. Inhibition of autophagy by LY294002 blocked the decrease of intracellular and intranuclear ROS level. Besides, inhibition of autophagy by LY294002 abolished the protection of exogenous NAD+ against H2O2-induced cell necrotic death. Taken together, our findings indicate that that exogenous NAD+ administration suppresses H2O2-induced oxidative stress and protects RPE cells against PARP-1 mediated necrotic death through the up-regulation of autophagy. The results suggest that exogenous NAD+ administration might be potential value for the treatment of AMD. PMID:27240523

  4. Morphological and functional rescue in RCS rats after RPE cell line transplantation at a later stage of degeneration.

    Science.gov (United States)

    Wang, Shaomei; Lu, Bin; Girman, Sergej; Holmes, Toby; Bischoff, Nicolas; Lund, Raymond D

    2008-01-01

    It is well documented that grafting of cells in the subretinal space of Royal College of Surgeons (RCS) rats limits deterioration of vision and loss of photoreceptors if performed early in postnatal life. What is unclear is whether cells introduced later, when photoreceptor degeneration is already advanced, can still be effective. This possibility was examined in the present study, using the human retinal pigment epithelial cell line, ARPE-19. Dystrophic RCS rats (postnatal day [P] 60) received subretinal injection of ARPE-19 cells (2 x 10(5)/3 microL/eye). Spatial frequency was measured by recording optomotor responses at P100 and P150, and luminance threshold responses were recorded from the superior colliculus at P150. Retinas were stained with cresyl violet, retinal cell-specific markers, and a human nuclear marker. Control animals were injected with medium alone. Animals comparably treated with grafts at P21 were available for comparison. All animals were treated with immunosuppression. Later grafts preserved both spatial frequency and threshold responses over the control and delayed photoreceptor degeneration. There were two to three layers of rescued photoreceptors even at P150, compared with a scattered single layer in sham and untreated control retinas. Retinal cell marker staining showed an orderly array of the inner retinal lamination. The morphology of the second-order neurons was better preserved around the grafted area than in regions distant from graft. Sham injection had little effect in rescuing the photoreceptors. RPE cell line transplants delivered later in the course of degeneration can preserve not only the photoreceptors and inner retinal lamination but also visual function in RCS rats. However, early intervention can achieve better rescue.

  5. Retinal Pigmented Epithelial Cells Obtained from Human Induced Pluripotent Stem Cells Possess Functional Visual Cycle Enzymes in Vitro and in Vivo*

    Science.gov (United States)

    Maeda, Tadao; Lee, Mee Jee; Palczewska, Grazyna; Marsili, Stefania; Tesar, Paul J.; Palczewski, Krzysztof; Takahashi, Masayo; Maeda, Akiko

    2013-01-01

    Differentiated retinal pigmented epithelial (RPE) cells have been obtained from human induced pluripotent stem (hiPS) cells. However, the visual (retinoid) cycle in hiPS-RPE cells has not been adequately examined. Here we determined the expression of functional visual cycle enzymes in hiPS-RPE cells compared with that of isolated wild-type mouse primary RPE (mpRPE) cells in vitro and in vivo. hiPS-RPE cells appeared morphologically similar to mpRPE cells. Notably, expression of certain visual cycle proteins was maintained during cell culture of hiPS-RPE cells, whereas expression of these same molecules rapidly decreased in mpRPE cells. Production of the visual chromophore, 11-cis-retinal, and retinosome formation also were documented in hiPS-RPE cells in vitro. When mpRPE cells with luciferase activity were transplanted into the subretinal space of mice, bioluminance intensity was preserved for >3 months. Additionally, transplantation of mpRPE into blind Lrat−/− and Rpe65−/− mice resulted in the recovery of visual function, including increased electrographic signaling and endogenous 11-cis-retinal production. Finally, when hiPS-RPE cells were transplanted into the subretinal space of Lrat−/− and Rpe65−/− mice, their vision improved as well. Moreover, histological analyses of these eyes displayed replacement of dysfunctional RPE cells by hiPS-RPE cells. Together, our results show that hiPS-RPE cells can exhibit a functional visual cycle in vitro and in vivo. These cells could provide potential treatment options for certain blinding retinal degenerative diseases. PMID:24129572

  6. Methodologies for analysis of patterning in the mouse RPE sheet

    Science.gov (United States)

    Boatright, Jeffrey H.; Dalal, Nupur; Chrenek, Micah A.; Gardner, Christopher; Ziesel, Alison; Jiang, Yi; Grossniklaus, Hans E.

    2015-01-01

    Purpose Our goal was to optimize procedures for assessing shapes, sizes, and other quantitative metrics of retinal pigment epithelium (RPE) cells and contact- and noncontact-mediated cell-to-cell interactions across a large series of flatmount RPE images. Methods The two principal methodological advances of this study were optimization of a mouse RPE flatmount preparation and refinement of open-access software to rapidly analyze large numbers of flatmount images. Mouse eyes were harvested, and extra-orbital fat and muscles were removed. Eyes were fixed for 10 min, and dissected by puncturing the cornea with a sharp needle or a stab knife. Four radial cuts were made with iridectomy scissors from the puncture to near the optic nerve head. The lens, iris, and the neural retina were removed, leaving the RPE sheet exposed. The dissection and outcomes were monitored and evaluated by video recording. The RPE sheet was imaged under fluorescence confocal microscopy after staining for ZO-1 to identify RPE cell boundaries. Photoshop, Java, Perl, and Matlab scripts, as well as CellProfiler, were used to quantify selected parameters. Data were exported into Excel spreadsheets for further analysis. Results A simplified dissection procedure afforded a consistent source of images that could be processed by computer. The dissection and flatmounting techniques were illustrated in a video recording. Almost all of the sheet could be routinely imaged, and substantial fractions of the RPE sheet (usually 20–50% of the sheet) could be analyzed. Several common technical problems were noted and workarounds developed. The software-based analysis merged 25 to 36 images into one and adjusted settings to record an image suitable for large-scale identification of cell-to-cell boundaries, and then obtained quantitative descriptors of the shape of each cell, its neighbors, and interactions beyond direct cell–cell contact in the sheet. To validate the software, human- and computer

  7. Ultraviolet (UV and Hydrogen Peroxide Activate Ceramide-ER Stress-AMPK Signaling Axis to Promote Retinal Pigment Epithelium (RPE Cell Apoptosis

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    Jin Yao

    2013-05-01

    Full Text Available Ultraviolet (UV radiation and reactive oxygen species (ROS impair the physiological functions of retinal pigment epithelium (RPE cells by inducing cell apoptosis, which is the main cause of age-related macular degeneration (AMD. The mechanism by which UV/ROS induces RPE cell death is not fully addressed. Here, we observed the activation of a ceramide-endoplasmic reticulum (ER stress-AMP activated protein kinase (AMPK signaling axis in UV and hydrogen peroxide (H2O2-treated RPE cells. UV and H2O2 induced an early ceramide production, profound ER stress and AMPK activation. Pharmacological inhibitors against ER stress (salubrinal, ceramide production (fumonisin B1 and AMPK activation (compound C suppressed UV- and H2O2-induced RPE cell apoptosis. Conversely, cell permeable short-chain C6 ceramide and AMPK activator AICAR (5-amino-1-β-D-ribofuranosyl-imidazole-4-carboxamide mimicked UV and H2O2’s effects and promoted RPE cell apoptosis. Together, these results suggest that UV/H2O2 activates the ceramide-ER stress-AMPK signaling axis to promote RPE cell apoptosis.

  8. 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.

  9. Efflux protein expression in human stem cell-derived retinal pigment epithelial cells.

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    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.

  10. Hyperglycaemia exacerbates choroidal neovascularisation in mice via the oxidative stress-induced activation of STAT3 signalling in RPE cells.

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    Xia Li

    Full Text Available Choroidal neovascularisation (CNV that occurs as a result of age-related macular degeneration (AMD causes severe vision loss among elderly patients. The relationship between diabetes and CNV remains controversial. However, oxidative stress plays a critical role in the pathogenesis of both AMD and diabetes. In the present study, we investigated the influence of diabetes on experimentally induced CNV and on the underlying molecular mechanisms of CNV. CNV was induced via photocoagulation in the ocular fundi of mice with streptozotocin-induced diabetes. The effect of diabetes on the severity of CNV was measured. An immunofluorescence technique was used to determine the levels of oxidative DNA damage by anti-8-hydroxy-2-deoxyguanosine (8-OHdG antibody, the protein expression of phosphorylated signal transducer and activator of transcription 3 (p-STAT3 and vascular endothelial growth factor (VEGF, in mice with CNV. The production of reactive oxygen species (ROS in retinal pigment epithelial (RPE cells that had been cultured under high glucose was quantitated using the 2',7'-dichlorofluorescein diacetate (DCFH-DA method. p-STAT3 expression was examined using Western blot analysis. RT-PCR and ELISA processes were used to detect VEGF expression. Hyperglycaemia exacerbated the development of CNV in mice. Oxidative stress levels and the expression of p-STAT3 and VEGF were highly elevated both in mice and in cultured RPE cells. Treatment with the antioxidant compound N-acetyl-cysteine (NAC rescued the severity of CNV in diabetic mice. NAC also inhibited the overexpression of p-STAT3 and VEGF in CNV and in RPE cells. The JAK-2/STAT3 pathway inhibitor AG490 blocked VEGF expression but had no effect on the production of ROS in vitro. These results suggest that hyperglycaemia promotes the development of CNV by inducing oxidative stress, which in turn activates STAT3 signalling in RPE cells. Antioxidant supplementation helped attenuate the development of CNV

  11. Lack of FasL expression in cultured human retinal pigment epithelial cells

    DEFF Research Database (Denmark)

    Kaestel, C G; Madsen, H O; Prause, J U

    2001-01-01

    Retinal pigment epithelial (RPE) cells have been proposed to play a part in maintaining the eye as an immune privileged organ. However, our knowledge of the implicated mechanism is still sparse. Fas ligand (FasL) expression of RPE cells is generally recognized to be essential for the immune...... privilege of the eye, but due to contradictory published results, it is unclear whether RPE cells express this molecule. The purpose of this study was to investigate the expression of FasL in RPE cells in vitro and in vivo. Cultured human fetal and adult RPE cells were examined by flow cytometry, Western...... blotting, RT-PCR and RNase Protection assay for FasL expression. Additionally, sections of ocular tissue were stained for FasL by immunohistochemistry. None of the used methods indicated FasL expression in cultured fetal or adult RPE cells of various passages. However, RPE cells in vivo, as judged from...

  12. A human apoB100 transgenic mouse expresses human apoB100 in the RPE and develops features of early AMD

    DEFF Research Database (Denmark)

    Fujihara, Masashi; Bartels, Emil; Nielsen, Lars B

    2009-01-01

    changes consistent with early human AMD including loss of basal infoldings and accumulation of cytoplasmic vacuoles in the RPE, and basal laminar deposits containing long-spacing collagen and heterogeneous debris in Bruch membrane of apoB100 mice. In apoB100 mice given a high-fat diet, basal linear...... transgenic for a human genomic fragment encoding the full length human apoB ("apoB100" mice) and litter-mate control mice were given a normal chow or high-fat diet for 12 months. Mice were evaluated for human apoB mRNA expression in the RPE/choroid and liver by RT-qPCR. Phenotypic changes associated......-like deposits were identified in 12-month-old mice. Linear regression analysis showed that the genotype (human apoB transgene) was a stronger influencing factor than high-fat diet in producing AMD-like lesions used in this study. Human apoB100 transgenic mice overexpress apoB in RPE and, with time, develop...

  13. Mechanism of RPE cell death in α-crystallin deficient mice: a novel and critical role for MRP1-mediated GSH efflux.

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    Parameswaran G Sreekumar

    Full Text Available Absence of α-crystallins (αA and αB in retinal pigment epithelial (RPE cells renders them susceptible to oxidant-induced cell death. We tested the hypothesis that the protective effect of α-crystallin is mediated by changes in cellular glutathione (GSH and elucidated the mechanism of GSH efflux. In α-crystallin overexpressing cells resistant to cell death, cellular GSH was >2 fold higher than vector control cells and this increase was seen particularly in mitochondria. The high GSH levels associated with α-crystallin overexpression were due to increased GSH biosynthesis. On the other hand, cellular GSH was decreased by 50% in murine retina lacking αA or αB crystallin. Multiple multidrug resistance protein (MRP family isoforms were expressed in RPE, among which MRP1 was the most abundant. MRP1 was localized to the plasma membrane and inhibition of MRP1 markedly decreased GSH efflux. MRP1-suppressed cells were resistant to cell death and contained elevated intracellular GSH and GSSG. Increased GSH in MRP1-supressed cells resulted from a higher conversion of GSSG to GSH by glutathione reductase. In contrast, GSH efflux was significantly higher in MRP1 overexpressing RPE cells which also contained lower levels of cellular GSH and GSSG. Oxidative stress further increased GSH efflux with a decrease in cellular GSH and rendered cells apoptosis-prone. In conclusion, our data reveal for the first time that 1 MRP1 mediates GSH and GSSG efflux in RPE cells; 2 MRP1 inhibition renders RPE cells resistant to oxidative stress-induced cell death while MRP1 overexpression makes them susceptible and 3 the antiapoptotic function of α-crystallin in oxidatively stressed cells is mediated in part by GSH and MRP1. Our findings suggest that MRP1 and α crystallin are potential therapeutic targets in pathological retinal degenerative disorders linked to oxidative stress.

  14. Protective effect of bone morphogenetic protein 6 on RPE cells injury caused by H2O2

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    Li Chen

    2016-01-01

    Full Text Available AIM:To investigate the effect of bone morphogenetic protein 6(BMP-6on cellular morphology, proliferation and apoptosis of retinal pigment epithelial cells(ARPE-19incubated in hydrogen peroxide(H2O2. METHODS:ARPE-19 cells were cultured conventionally and divided into four groups. One group was untreated as blank group, the other three groups were incubated in 75μm/L H2O2, 150ng/mLBMP-6 or75μm/L H2O2+150ng/mL BMP-6. All the groups were incubated for 3h, 6h, 9h and 12h. We tested the cell viabilitity by MTT. We used flow cytometry to test the cell cycle and cell apoptosis.RESULTS:H2O2 significantly decreased the cell activity in time-dependent manner. The activity of cells with BMP-6+H2O2 was higher H2O2 group, and the differences between the two groups at 3h and 6h were significant(P2O2, while the cells with BMP-6 were less cell detachment and apoptosis. CONCLUSION:BMP-6 has protective effects on RPE cells from oxidative stress in certain extent.

  15. Gremlin promotes retinal pigmentation epithelial (RPE) cell proliferation, migration and VEGF production via activating VEGFR2-Akt-mTORC2 signaling.

    Science.gov (United States)

    Liu, Yuan; Chen, Zhijun; Cheng, Haixia; Chen, Juan; Qian, Jing

    2017-01-03

    Retinopathy of prematurity (ROP) is characterized by late-phase pathologic retinal vasoproliferation. Gremlin is a novel vascular endothelial growth factors (VEGF) receptor 2 (VEGFR2) agonist and promotes angiogenic response. We demonstrated that gremlin expression was significantly increased in retinas of ROP model mice, which was correlated with VEGF upregulation. In retinal pigmentation epithelial (RPE) cells, gremlin activated VEGFR2-Akt-mTORC2 (mammalian target of rapamycin complex 2) signaling, and promoted cell proliferation, migration and VEGF production. VEGFR inhibition (by SU5416) or shRNA knockdown almost abolished gremlin-mediated pleiotropic functions in RPE cells. Further, pharmacological inhibition of Akt-mTOR, or shRNA knockdown of key mTORC2 component (Rictor or Sin1) also attenuated gremlin-exerted activities in RPE cells. We conclude that gremlin promotes RPE cell proliferation, migration and VEGF production possibly via activating VEGFR2-Akt-mTORC2 signaling. Gremlin could be a novel therapeutic target of ROP or other retinal vasoproliferation diseases.

  16. Behavior of a Spontaneously Arising Human Retinal Pigment Epithelial Cell Line Cultivated on Thin Alginate Film.

    Science.gov (United States)

    Najafabadi, Hoda Shams; Soheili, Zahra-Soheila; Ganji, Shahla Mohammad

    2015-01-01

    A cell line spontaneously derived from human retinal pigment epithelium (hRPE) was cultured on alginate film gelatinized with different concentrations of neurobasal cell culture medium (NCCM) to assess its growth and morphological behavior on this naturally occurring polysaccharide. Neonatal human globes were used to isolate hRPE cells. They were cultured in Dulbecco's modified Eagle's-medium-and-Ham's-F12-medium-(DMEM/F12) supplemented with 10% fetal bovine serum (FBS). Cultures were continuously studied using phase contrast microscopy. After the nineth passage, cells were characterized through immunocytochemical analysis for Oct4, Chx10, and Pax6 and Ki67 markers. In each well of a 6-well microplate, 1 and 2% weight/volume (w/v) alginate in deionized water was added and gelatinized using 1× and 10× NCCM. hRPE cells were cultured at a density of 2 × 105 cells/well in alginate-coated microplates. After 5 days, hRPE colonies were harvested and re-plated on polystyrene substrates. Morphology and growth of hRPE cultures were determined during the next 2 weeks. The first few passages of the cultures were purely hRPE cells that revealed typical morphological features of the pigmented epithelium. They made spaces, devoid of cells, between hRPE cell monolayer and fill in the unoccupied spaces. They grew faster than native RPE cells and rapidly overgrew. Immunocytochemical test revealed that the founded cells expressed Chx10, Pax6, Ki67 and Oct4. The hRPE cells survived unlimitedly on alginate film and formed giant adjoining colonies. After re-plating, hRPE colonies adhered quickly on polystyrene and displayed native hRPE morphological features. Alginate film can support the survival and growth of hRPE cells and induce the cells to re-organize in tissue-like structures.

  17. Two-photon excited autofluorescence imaging of human retinal pigment epithelial cells

    Science.gov (United States)

    Han, Meng; Blindewald-Wittich, Almut; Holz, Frank G.; Giese, Günter; Niemz, Markolf H.; Snyder, Sarah; Sun, Hui; Yu, Jiayi; Agopov, Michael; La Schiazza, Olivier; Bille, Josef F.

    2006-01-01

    Degeneration of retinal pigment epithelial (RPE) cells severely impairs the visual function of retina photoreceptors. However, little is known about the events that trigger the death of RPE cells at the subcellular level. Two-photon excited autofluorescence (TPEF) imaging of RPE cells proves to be well suited to investigate both the morphological and the spectral characteristics of the human RPE cells. The dominant fluorophores of autofluorescence derive from lipofuscin (LF) granules that accumulate in the cytoplasm of the RPE cells with increasing age. Spectral TPEF imaging reveals the existence of abnormal LF granules with blue shifted autofluorescence in RPE cells of aging patients and brings new insights into the complicated composition of the LF granules. Based on a proposed two-photon laser scanning ophthalmoscope, TPEF imaging of the living retina may be valuable for diagnostic and pathological studies of age related eye diseases.

  18. The immune privilege of the eye: human retinal pigment epithelial cells selectively modulate T-cell activation in vitro

    DEFF Research Database (Denmark)

    Kaestel, Charlotte G; Lovato, Paola; Ødum, Niels

    2005-01-01

    PURPOSE: To examine the effect of human retinal pigment epithelial (RPE) cells on phytohemagglutinin (PHA) activation of T cells. METHODS: Resting peripheral blood lymphocytes (PBLs) were stimulated with PHA with or without the presence of gamma-irradiated RPE cells. Proliferation and the cell...... in cell culture supernatant was measured by ELISA. RESULTS: Human RPE cells were found to suppress PHA-induced proliferation, cyclin A, IL-2R-alpha and -gamma, and CD71 expression and decrease the production of IL-2; but RPE cells do not inhibit the PHA-induced expression of early activation markers CD69......, MHC class I and II, and of cyclin D of the PBLs. CONCLUSIONS: These results are the first to indicate that RPE cells impede generation of activated T cells by interfering with the induction of high-affinity IL-2R-alphabetagamma, IL-2 production, and the expression of CD71 and cyclin A....

  19. 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...

  20. Induced Retro-Differentiation of Human Retinal Pigment Epithelial Cells on PolyHEMA.

    Science.gov (United States)

    Nazemroaya, Fatemeh; Soheili, Zahra-Soheila; Samiei, Shahram; Deezagi, Abdolkhalegh; Ahmadieh, Hamid; Davari, Malihe; Heidari, Razeih; Bagheri, Abouzar; Darvishalipour-Astaneh, Shamila

    2017-10-01

    Retinal pigment epithelium (RPE) cells represent a great potential to rescue degenerated cells of the damaged retina. Activation of the virtually plastic properties of RPE cells may aid in recovery of retinal degenerative disorders without the need for entire RPE sheet transplantation. Poly (2-hydroxyethyl methacrylate)(PolyHEMA) is one of the most important hydrogels in the biomaterials world. This hydrophobic polymer does not normally support attachment of mammalian cells. In the current study we investigated the effect of PolyHEMA as a cell culture substrate on the growth, differentiation, and plasticity of hRPE cells. hRPE cells were isolated from neonatal human globes and cultured on PolyHEMA and polystyrene substrates (as controls) in 24-well culture plates. DMEM/F12 was supplemented with 10% fetal bovine serum (FBS) and/or 30% human amniotic fluid (HAF) for cultured cells on polystyrene and PolyHEMA coated vessels. Morphology, rate of cell proliferation and cell death, MTT assay, immunocytochemistry and Real-Time RT-PCR were performed to investigate the effects of PolyHEMA on the growth and differentiation of cultured hRPE cells. Proliferation rate of the cells that had been cultured on PolyHEMA was reduced; PolyHEMA did not induce cell death in the hRPE cultures. hRPE cells cultured on PolyHEMA formed many giant spheroid colonies. The giant colonies were re-cultured and the presence of retinal progenitor markers and markers of hRPE cells were detected in cell cultures on PolyHEMA. PolyHEMA seems to be promising for both maintenance and de-differentiation of hRPE cells and expansion of the retinal progenitor cells from the cultures that are originated from hRPE cells. J. Cell. Biochem. 118: 3080-3089, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  1. 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.

  2. Contacting co-culture of human retinal microvascular endothelial cells alters barrier function of human embryonic stem cell derived retinal pigment epithelial cells.

    Science.gov (United States)

    Skottman, H; Muranen, J; Lähdekorpi, H; Pajula, E; Mäkelä, K; Koivusalo, L; Koistinen, A; Uusitalo, H; Kaarniranta, K; Juuti-Uusitalo, K

    2017-10-01

    Here we evaluated the effects of human retinal microvascular endothelial cells (hREC) on mature human embryonic stem cell (hESC) derived retinal pigment epithelial (RPE) cells. The hESC-RPE cells (Regea08/017, Regea08/023 or Regea11/013) and hREC (ACBRI 181) were co-cultured on opposite sides of transparent membranes for up to six weeks. Thereafter barrier function, small molecule permeability, localization of RPE and endothelial cell marker proteins, cellular fine structure, and growth factor secretion of were evaluated. After co-culture, the RPE specific CRALBP and endothelial cell specific von Willebrand factor were appropriately localized. In addition, the general morphology, pigmentation, and fine structure of hESC-RPE cells were unaffected. Co-culture increased the barrier function of hESC-RPE cells, detected both with TEER measurements and cumulative permeability of FD4 - although the differences varied among the cell lines. Co-culturing significantly altered VEGF and PEDF secretion, but again the differences were cell line specific. The results of this study showed that co-culture with hREC affects hESC-RPE functionality. In addition, co-culture revealed drastic cell line specific differences, most notably in growth factor secretion. This model has the potential to be used as an in vitro outer blood-retinal barrier model for drug permeability testing. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Patient-specific mutations impair BESTROPHIN1’s essential role in mediating Ca2+-dependent Cl- currents in human RPE

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yao [Jonas Children’s Vision Care, and Bernard and Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology and Pathology & Cell Biology, Edward S. Harkness Eye Institute, New York Presbyterian Hospital/Columbia University, New York, United States; Zhang, Yu [Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, United States; Xu, Yu [Jonas Children’s Vision Care, and Bernard and Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology and Pathology & Cell Biology, Edward S. Harkness Eye Institute, New York Presbyterian Hospital/Columbia University, New York, United States; Department of Ophthalmology, Xinhua Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China; Kittredge, Alec [Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, United States; Ward, Nancy [Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, United States; Chen, Shoudeng [Molecular Imaging Center, Department of Experimental Medicine, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China; Tsang, Stephen H. [Jonas Children’s Vision Care, and Bernard and Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology and Pathology & Cell Biology, Edward S. Harkness Eye Institute, New York Presbyterian Hospital/Columbia University, New York, United States; Yang, Tingting [Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, United States

    2017-10-24

    Mutations in the human BEST1 gene lead to retinal degenerative diseases displaying progressive vision loss and even blindness. BESTROPHIN1, encoded by BEST1, is predominantly expressed in retinal pigment epithelium (RPE), but its physiological role has been a mystery for the last two decades. Using a patient-specific iPSC-based disease model and interdisciplinary approaches, we comprehensively analyzed two distinct BEST1 patient mutations, and discovered mechanistic correlations between patient clinical phenotypes, electrophysiology in their RPEs, and the structure and function of BESTROPHIN1 mutant channels. Our results revealed that the disease-causing mechanism of BEST1 mutations is centered on the indispensable role of BESTROPHIN1 in mediating the long speculated Ca2+-dependent Cl- current in RPE, and demonstrate that the pathological potential of BEST1 mutations can be evaluated and predicted with our iPSC-based ‘disease-in-a-dish’ approach. Moreover, we demonstrated that patient RPE is rescuable with viral gene supplementation, providing a proof-of-concept for curing BEST1-associated diseases.

  4. 17-AAG, a Hsp90 inhibitor, attenuates the hypoxia-induced expression of SDF-1alpha and ILK in mouse RPE cells.

    Science.gov (United States)

    Wang, Ye Qing; Zhang, Xiao Mei; Wang, Xiao Dan; Wang, Bin Jie; Wang, Wei

    2010-03-01

    The aim of this study was to investigate the changes of SDF-1alpha and ILK expression in mouse retinal pigment epithelium (RPE) cells in response to hypoxia, and the effect of 17-Allylamino-17-demethoxygeldanamycin (17-AAG), a heat shock protein 90 (Hsp90) inhibitor, on the hypoxia-induced expression of SDF-1alpha and ILK. RPE cells were cultured with 200 micromol/L cobalt chloride (CoCl(2)) for different times (1, 3, 6, 12, 24, 72 h) to imitate chemical hypoxia. Pretreatment of 17-AAG was 1 h prior to hypoxic insult. Cellular viability after 17-AAG treatment was assessed by MTT assay, and the changes of SDF-1alpha and ILK expression were examined by RT-PCR and Western blot. Up-regulation of SDF-1alpha and ILK expression in response to hypoxia was observed. One hour pretreatment of 17-AAG could remarkably decreased the hypoxia-induced SDF-1alpha and ILK expression in vitro. Our results indicated that SDF-1alpha and ILK involved in the hypoxic response of RPE cells, and 1 h pretreatment of 17-AAG had an inhibitive effect on the hypoxia-induced SDF-1alpha and ILK expression.

  5. Rapid, Directed Differentiation of Retinal Pigment Epithelial Cells from Human Embryonic or Induced Pluripotent Stem Cells

    OpenAIRE

    Foltz, LP; Clegg, DO

    2017-01-01

    We describe a robust method to direct the differentiation of pluripotent stem cells into retinal pigment epithelial cells (RPE). The purpose of providing a detailed and thorough protocol is to clearly demonstrate each step and to make this readily available to researchers in the field. This protocol results in a homogenous layer of RPE with minimal or no manual dissection needed. The method presented here has been shown to be effective for induced pluripotent stem cells (iPSC) and human embry...

  6. Age-related changes in the retinal pigment epithelium (RPE.

    Directory of Open Access Journals (Sweden)

    Xiaorong Gu

    Full Text Available Age-related changes in the retina are often accompanied by visual impairment but their mechanistic details remain poorly understood.Proteomic studies were pursued toward a better molecular understanding of retinal pigment epithelium (RPE aging mechanisms. RPE cells were isolated from young adults (3-4 month-old and old (24-25 month-old F344BN rats, and separated into subcellular fractions containing apical microvilli (MV and RPE cell bodies (CB lacking their apical microvilli. Proteins were extracted in detergent, separated by SDS-PAGE, digested in situ with trypsin and analyzed by LC MS/MS. Select proteins detected in young and old rat RPE were further studied using immunofluorescence and Western blot analysis.A total of 356 proteins were identified in RPE MV from young and 378 in RPE MV from old rats, 48% of which were common to each age group. A total of 897 proteins were identified in RPE CB from young rats and 675 in old CB, 56% of which were common to each age group. Several of the identified proteins, including proteins involved in response to oxidative stress, displayed both quantitative and qualitative changes in overall abundance during RPE aging. Numerous proteins were identified for the first time in the RPE. One such protein, collectrin, was localized to the apical membrane of apical brush border of proximal tubules where it likely regulates several amino acid transporters. Elsewhere, collectrin is involved in pancreatic β cell proliferation and insulin secretion. In the RPE, collectrin expression was significantly modulated during RPE aging. Another age-regulated, newly described protein was DJ-1, a protein extensively studied in brain where oxidative stress-related functions have been described.The data presented here reveals specific changes in the RPE during aging, providing the first protein database of RPE aging, which will facilitate future studies of age-related retinal diseases.

  7. Neonatal human retinal pigment epithelial cells secrete limited trophic factors in vitro and in vivo following striatal implantation in parkinsonian rats

    DEFF Research Database (Denmark)

    Russ, Kaspar; Flores, Joseph; Brudek, Tomasz

    2015-01-01

    Human retinal pigment epithelial (hRPE) cell implants into the striatum have been investigated as a potential cell-based treatment for Parkinson's disease in a Phase II clinical trial that recently failed. We hypothesize that the trophic factor potential of the hRPE cells could potentially influe...

  8. PlGF gene knockdown in human retinal pigment epithelial cells.

    Science.gov (United States)

    Akrami, Hassan; Soheili, Zahra-Soheila; Sadeghizadeh, Majid; Ahmadieh, Hamid; Rezaeikanavi, Mozhgan; Samiei, Shahram; Khalooghi, Keynoush

    2011-04-01

    To evaluate the knockdown of placental growth factor (PlGF) gene expression in human retinal pigment epithelium (RPE) cells and its effect on cell proliferation, apoptosis and angiogenic potential of RPE cells. Human RPE cells were isolated by dispase I solution and cultured in DMEM/F12 supplemented with 10% fetal calf serum (FCS). A small interfering RNA (siRNA) corresponding to PlGF mRNA and a scrambled siRNA (scRNA) were introduced into the cells. Cell proliferation and cell death were examined by ELISA. PlGF mRNA and protein were quantified by real-time polymerase chain reaction (PCR) and western blot. The levels of gene expression for human retinal pigment epithelium-specific protein 65 kDa (RPE65), cellular retinaldehyde-binding protein (CRALBP) and tyrosinase were examined by real-time PCR. The angiogenic activity of RPE cell-derived conditioned media was assayed by a tube formation assay using human umbilical vein endothelial cells (HUVECs). At a final siRNA concentration of 20 pmol/ml, the transfection efficiency was about 80%. The amount of PlGF transcripts was reduced to 10% after 36 h of incubation, and the amount of PlGF protein in culture supernatant was significantly decreased. Suppression of PlGF gene had no effect on RPE cell proliferation and survival, and there were no notable changes in the transcript levels of RPE65, CRALBP or tyrosinase for the cultures treated by siRNA cognate to PlGF. Vascular tube formation was efficiently reduced in HUVECs. Our findings present PlGF as a key modulator of angiogenic potential in RPE cells of the human retina.

  9. Novel Epigenetic Controlling of Hypoxia Pathway Related to Overexpression and Promoter Hypomethylation of TET1 and TET2 in RPE Cells.

    Science.gov (United States)

    Alivand, Mohammad Reza; Soheili, Zahra-Soheila; Pornour, Majid; Solali, Saeed; Sabouni, Farzaneh

    2017-10-01

    CpG methylation of DNA takes part in a specific epigenetic memory that plays crucial roles in the differentiation and abnormality of the cells. The methylation pattern aberration of genomes is affected in three ways, namely DNA methyltransferase (DNMT), ten-eleven translocation (TET), and methyl-binding domain (MBD) proteins. Of these, TET enzymes have recently been demonstrated to be master modifier enzymes in the DNA methylation process. Additionally, recent studies emphasize that not only epigenetic phenomena play a role in controlling hypoxia pathway, but the hypoxia condition also triggers hypomethylation of genomes that may help with the expression of hypoxia pathway genes. In this study, we suggested that TET1 and TET2 could play a role in the demethylation of genomes under chemical hypoxia conditions. Herein, the evaluating methylation status and mRNA expression of mentioned genes were utilized through real-time PCR and methylation-specific PCR (MSP), respectively. Our results showed that TET1 and TET2 genes were overexpressed (P < 0.05) under chemical hypoxia conditions in Retinal Pigment Epithelial (RPE) cells, whereas the promoter methylation status of them were hypomethylated in the same condition. Therefore, chemical hypoxia not only causes overexpression of TET1 and TET2 but also could gradually do promoter demethylation of same genes. This is the first study to show the relationship between epigenetics and the expression of mentioned genes related to hypoxia pathways. Furthermore, it seems that these associations in RPE cells are subjected to chemical hypoxia as a mechanism that could play a crucial role in methylation pattern changes of hypoxia-related diseases such as cancer and ischemia. J. Cell. Biochem. 118: 3193-3204, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. Application of stem cell-derived retinal pigmented epithelium in retinal degenerative diseases: present and future

    Directory of Open Access Journals (Sweden)

    Mingyue Luo

    2018-01-01

    Full Text Available As a constituent of blood-retinal barrier and retinal outer segment (ROS scavenger, retinal pigmented epithelium (RPE is fundamental to normal function of retina. Malfunctioning of RPE contributes to the onset and advance of retinal degenerative diseases. Up to date, RPE replacement therapy is the only possible method to completely reverse retinal degeneration. Transplantation of human RPE stem cell-derived RPE (hRPESC-RPE has shown some good results in animal models. With promising results in terms of safety and visual improvement, human embryonic stem cell-derived RPE (hESC-RPE can be expected in clinical settings in the near future. Despite twists and turns, induced pluripotent stem cell-derived RPE (iPSC-RPE is now being intensely investigated to overcome genetic and epigenetic instability. By far, only one patient has received iPSC-RPE transplant, which is a hallmark of iPSC technology development. During follow-up, no major complications such as immunogenicity or tumorigenesis have been observed. Future trials should keep focusing on the safety of stem cell-derived RPE (SC-RPE especially in long period, and better understanding of the nature of stem cell and the molecular events in the process to generate SC-RPE is necessary to the prosperity of SC-RPE clinical application.

  11. Application of stem cell-derived retinal pigmented epithelium in retinal degenerative diseases: present and future.

    Science.gov (United States)

    Luo, Mingyue; Chen, Youxin

    2018-01-01

    As a constituent of blood-retinal barrier and retinal outer segment (ROS) scavenger, retinal pigmented epithelium (RPE) is fundamental to normal function of retina. Malfunctioning of RPE contributes to the onset and advance of retinal degenerative diseases. Up to date, RPE replacement therapy is the only possible method to completely reverse retinal degeneration. Transplantation of human RPE stem cell-derived RPE (hRPESC-RPE) has shown some good results in animal models. With promising results in terms of safety and visual improvement, human embryonic stem cell-derived RPE (hESC-RPE) can be expected in clinical settings in the near future. Despite twists and turns, induced pluripotent stem cell-derived RPE (iPSC-RPE) is now being intensely investigated to overcome genetic and epigenetic instability. By far, only one patient has received iPSC-RPE transplant, which is a hallmark of iPSC technology development. During follow-up, no major complications such as immunogenicity or tumorigenesis have been observed. Future trials should keep focusing on the safety of stem cell-derived RPE (SC-RPE) especially in long period, and better understanding of the nature of stem cell and the molecular events in the process to generate SC-RPE is necessary to the prosperity of SC-RPE clinical application.

  12. 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...

  13. Effects of the Macular Carotenoid Lutein in Human Retinal Pigment Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Xiaoming Gong

    2017-12-01

    Full Text Available Retinal pigment epithelial (RPE cells are central to retinal health and homoeostasis. Oxidative stress-induced damage to the RPE occurs as part of the pathogenesis of age-related macular degeneration and neovascular retinopathies (e.g., retinopathy of prematurity, diabetic retinopathy. The xanthophyll carotenoids, lutein and zeaxanthin, are selectively taken up by the RPE, preferentially accumulated in the human macula, and transferred to photoreceptors. These macular xanthophylls protect the macula (and the broader retina via their antioxidant and photo-protective activities. This study was designed to investigate effects of various carotenoids (β-carotene, lycopene, and lutein on RPE cells subjected to either hypoxia or oxidative stress, in order to determine if there is effect specificity for macular pigment carotenoids. Using human RPE-derived ARPE-19 cells as an in vitro model, we exposed RPE cells to various concentrations of the specific carotenoids, followed by either graded hypoxia or oxidative stress using tert-butyl hydroperoxide (tBHP. The results indicate that lutein and lycopene, but not β-carotene, inhibit cell growth in undifferentiated ARPE-19 cells. Moreover, cell viability was decreased under hypoxic conditions. Pre-incubation of ARPE-19 cells with lutein or lycopene protected against tBHP-induced cell loss and cell co-exposure of lutein or lycopene with tBHP essentially neutralized tBHP-dependent cell death at tBHP concentrations up to 500 μM. Our findings indicate that lutein and lycopene inhibit the growth of human RPE cells and protect the RPE against oxidative stress-induced cell loss. These findings contribute to the understanding of the protective mechanisms attributable to retinal xanthophylls in eye health and retinopathies.

  14. Human retinal pigment epithelial cells inhibit proliferation and IL2R expression of activated T cells

    DEFF Research Database (Denmark)

    Kaestel, Charlotte G; Jørgensen, Annette; Nielsen, Mette

    2002-01-01

    -Thymidine incorporation assay, respectively. T cells and RPE cells were cultured directly together or in a transwell system for determination of the effect of cell contact. The importance of cell surface molecules was examined by application of a panel of blocking antibodies (CD2, CD18, CD40, CD40L, CD54, CD58......) in addition to use of TCR negative T cell lines. The expression of IL2R-alpha -beta and -gamma chains of activated T cells was analysed by flow cytometry after incubation of T cells alone or with RPE cells. Human RPE cells were found to inhibit the proliferation of activated T cells by a cell contact......-beta and -gamma chain expression within 24 hr after removal from the coculture. It is concluded that the cultured human adult and foetal RPE cells inhibit the proliferation of activated T cells by a process that does not involve apoptosis. It depends on cell contact but the involved surface molecules were...

  15. Comparative study of human embryonic stem cells (hESC) and human induced pluripotent stem cells (hiPSC) as a treatment for retinal dystrophies

    Science.gov (United States)

    Riera, Marina; Fontrodona, Laura; Albert, Silvia; Ramirez, Diana Mora; Seriola, Anna; Salas, Anna; Muñoz, Yolanda; Ramos, David; Villegas-Perez, Maria Paz; Zapata, Miguel Angel; Raya, Angel; Ruberte, Jesus; Veiga, Anna; Garcia-Arumi, Jose

    2016-01-01

    Retinal dystrophies (RD) are major causes of familial blindness and are characterized by progressive dysfunction of photoreceptor and/or retinal pigment epithelium (RPE) cells. In this study, we aimed to evaluate and compare the therapeutic effects of two pluripotent stem cell (PSC)-based therapies. We differentiated RPE from human embryonic stem cells (hESCs) or human-induced pluripotent stem cells (hiPSCs) and transplanted them into the subretinal space of the Royal College of Surgeons (RCS) rat. Once differentiated, cells from either source of PSC resembled mature RPE in their morphology and gene expression profile. Following transplantation, both hESC- and hiPSC-derived cells maintained the expression of specific RPE markers, lost their proliferative capacity, established tight junctions, and were able to perform phagocytosis of photoreceptor outer segments. Remarkably, grafted areas showed increased numbers of photoreceptor nuclei and outer segment disk membranes. Regardless of the cell source, human transplants protected retina from cell apoptosis, glial stress and accumulation of autofluorescence, and responded better to light stimuli. Altogether, our results show that hESC- and hiPSC-derived cells survived, migrated, integrated, and functioned as RPE in the RCS rat retina, providing preclinical evidence that either PSC source could be of potential benefit for treating RD. PMID:27006969

  16. Comparative study of human embryonic stem cells (hESC and human induced pluripotent stem cells (hiPSC as a treatment for retinal dystrophies

    Directory of Open Access Journals (Sweden)

    Marina Riera

    2016-01-01

    Full Text Available Retinal dystrophies (RD are major causes of familial blindness and are characterized by progressive dysfunction of photoreceptor and/or retinal pigment epithelium (RPE cells. In this study, we aimed to evaluate and compare the therapeutic effects of two pluripotent stem cell (PSC-based therapies. We differentiated RPE from human embryonic stem cells (hESCs or human-induced pluripotent stem cells (hiPSCs and transplanted them into the subretinal space of the Royal College of Surgeons (RCS rat. Once differentiated, cells from either source of PSC resembled mature RPE in their morphology and gene expression profile. Following transplantation, both hESC- and hiPSC-derived cells maintained the expression of specific RPE markers, lost their proliferative capacity, established tight junctions, and were able to perform phagocytosis of photoreceptor outer segments. Remarkably, grafted areas showed increased numbers of photoreceptor nuclei and outer segment disk membranes. Regardless of the cell source, human transplants protected retina from cell apoptosis, glial stress and accumulation of autofluorescence, and responded better to light stimuli. Altogether, our results show that hESC- and hiPSC-derived cells survived, migrated, integrated, and functioned as RPE in the RCS rat retina, providing preclinical evidence that either PSC source could be of potential benefit for treating RD.

  17. Human amniotic fluid promotes retinal pigmented epithelial cells' trans-differentiation into rod photoreceptors and retinal ganglion cells.

    Science.gov (United States)

    Ghaderi, Shima; Soheili, Zahra-Soheila; Ahmadieh, Hamid; Davari, Maliheh; Jahromi, Fatemeh Sanie; Samie, Shahram; Rezaie-Kanavi, Mozhgan; Pakravesh, Jalil; Deezagi, Abdolkhalegh

    2011-09-01

    To evaluate the effect of human amniotic fluid (HAF) on retinal pigmented epithelial cells growth and trans-differentiation into retinal neurons, retinal pigmented epithelium (RPE) cells were isolated from neonatal human cadaver eye globes and cultured in Dulbecco's modified Eagle's medium-F12 supplemented with 10% fetal bovine serum (FBS). Confluent monolayer cultures were trypsinized and passaged using FBS-containing or HAF-containing media. Amniotic fluid samples were received from pregnant women in the first trimester of gestation. Cell proliferation and death enzyme-linked immunosorbent assays were performed to assess the effect of HAF on RPE cell growth. Trans-differentiation into rod photoreceptors and retinal ganglion cells was also studied using immunocytochemistry and real-time polymerase chain reaction techniques. Primary cultures of RPE cells were successfully established under FBS-containing or HAF-containing media leading to rapid cell growth and proliferation. When RPE cells were moved to in vitro culture system, they began to lose their differentiation markers such as pigmentation and RPE65 marker and trans-differentiated neural-like cells followed by spheroid colonies pertaining to stem/progenitor cells were morphologically detected. Immunocytochemistry (ICC) analysis of HAF-treated cultures showed a considerable expression of Rhodopsin gene (30% Rhodopsin-positive cells) indicating trans-differentiation of RPE cells to rod photoreceptors. Real-time polymerase chain reaction revealed an HAF-dose-dependant expression of Thy-1 gene (RGC marker) and significant promoting effect of HAF on RGCs generation. The data presented here suggest that HAF possesses invaluable stimulatory effect on RPE cells growth and trans-differentiation into retinal neurons. It can be regarded as a newly introduced enriched supplement in serum-free kinds of media used in neuro-retinal regeneration studies.

  18. Study of Short-Pulsed Laser Retinal Injury Mechanisms By Time-Resolved Imaging of Photomechanical Transients in RPE

    National Research Council Canada - National Science Library

    Lin, Charles

    2000-01-01

    We studied RPE cell damage mechanism for laser duration from 100 femtosec to 5 microsec, and we have investigated the dependence of threshold fluence for cell damage on the laser spot size on the RPE...

  19. Noninvasive near infrared autofluorescence imaging of retinal pigment epithelial cells in the human retina using adaptive optics.

    Science.gov (United States)

    Liu, Tao; Jung, HaeWon; Liu, Jianfei; Droettboom, Michael; Tam, Johnny

    2017-10-01

    The retinal pigment epithelial (RPE) cells contain intrinsic fluorophores that can be visualized using infrared autofluorescence (IRAF). Although IRAF is routinely utilized in the clinic for visualizing retinal health and disease, currently, it is not possible to discern cellular details using IRAF due to limits in resolution. We demonstrate that the combination of adaptive optics (AO) with IRAF (AO-IRAF) enables higher-resolution imaging of the IRAF signal, revealing the RPE mosaic in the living human eye. Quantitative analysis of visualized RPE cells in 10 healthy subjects across various eccentricities demonstrates the possibility for in vivo density measurements of RPE cells, which range from 6505 to 5388 cells/mm 2 for the areas measured (peaking at the fovea). We also identified cone photoreceptors in relation to underlying RPE cells, and found that RPE cells support on average up to 18.74 cone photoreceptors in the fovea down to an average of 1.03 cone photoreceptors per RPE cell at an eccentricity of 6 mm. Clinical application of AO-IRAF to a patient with retinitis pigmentosa illustrates the potential for AO-IRAF imaging to become a valuable complementary approach to the current landscape of high resolution imaging modalities.

  20. LC-MS/MS Based Quantitation of ABC and SLC Transporter Proteins in Plasma Membranes of Cultured Primary Human Retinal Pigment Epithelium Cells and Immortalized ARPE19 Cell Line.

    Science.gov (United States)

    Pelkonen, Laura; Sato, Kazuki; Reinisalo, Mika; Kidron, Heidi; Tachikawa, Masanori; Watanabe, Michitoshi; Uchida, Yasuo; Urtti, Arto; Terasaki, Tetsuya

    2017-03-06

    The retinal pigment epithelium (RPE) forms the outer blood-retinal barrier between neural retina and choroid. The RPE has several important vision supporting functions, such as transport mechanisms that may also modify pharmacokinetics in the posterior eye segment. Expression of plasma membrane transporters in the RPE cells has not been quantitated. The aim of this study was to characterize and compare transporter protein expression in the ARPE19 cell line and hfRPE (human fetal RPE) cells by using quantitative targeted absolute proteomics (QTAP). Among 41 studied transporters, 16 proteins were expressed in hfRPE and 13 in ARPE19 cells. MRP1, MRP5, GLUT1, 4F2hc, TAUT, CAT1, LAT1, and MATE1 proteins were detected in both cell lines within 4-fold differences. MPR7, OAT2 and RFC1 were detected in the hfRPE cells, but their expression levels were below the limit of quantification in ARPE19 cells. PCFT was detected in both studied cell lines, but the expression was over 4-fold higher in hfRPE cells. MCT1, MCT4, MRP4, and Na + /K + ATPase were upregulated in the ARPE19 cell line showing over 4-fold differences in the quantitative expression values. Expression levels of 25 transporters were below the limit of quantification in both cell models. In conclusion, we present the first systematic and quantitative study on transporter protein expression in the plasma membranes of ARPE19 and hfRPE cells. Overall, transporter expression in the ARPE19 and hfRPE cells correlated well and the absolute expression levels were similar, but not identical. The presented quantitative expression levels could be a useful basis for further studies on drug permeation in the outer blood-retinal barrier.

  1. Subretinal Implantation of Retinal Pigment Epithelial Cells Derived From Human Embryonic Stem Cells: Improved Survival When Implanted as a Monolayer

    Science.gov (United States)

    Diniz, Bruno; Thomas, Padmaja; Thomas, Biju; Ribeiro, Ramiro; Hu, Yuntao; Brant, Rodrigo; Ahuja, Ashish; Zhu, Danhong; Liu, Laura; Koss, Michael; Maia, Mauricio; Chader, Gerald; Hinton, David R.; Humayun, Mark S.

    2013-01-01

    Purpose. To evaluate cell survival and tumorigenicity of human embryonic stem cell–derived retinal pigment epithelium (hESC-RPE) transplantation in immunocompromised nude rats. Cells were transplanted as a cell suspension (CS) or as a polarized monolayer plated on a parylene membrane (PM). Methods. Sixty-nine rats (38 male, 31 female) were surgically implanted with CS (n = 33) or PM (n = 36). Cohort subsets were killed at 1, 6, and 12 months after surgery. Both ocular tissues and systemic organs (brain, liver, kidneys, spleen, heart, and lungs) were fixed in 4% paraformaldehyde, embedded in paraffin, and sectioned. Every fifth section was stained with hematoxylin and eosin and analyzed histologically. Adjacent sections were processed for immunohistochemical analysis (as needed) using the following antibodies: anti-RPE65 (RPE-specific marker), anti-TRA-1-85 (human cell marker), anti-Ki67 (proliferation marker), anti-CD68 (macrophage), and anti-cytokeratin (epithelial marker). Results. The implanted cells were immunopositive for the RPE65 and TRA-1-85. Cell survival (P = 0.006) and the presence of a monolayer (P < 0.001) of hESC-RPE were significantly higher in eyes that received the PM. Gross morphological and histological analysis of the eye and the systemic organs after the surgery revealed no evidence of tumor or ectopic tissue formation in either group. Conclusions. hESC-RPE can survive for at least 12 months in an immunocompromised animal model. Polarized monolayers of hESC-RPE show improved survival compared to cell suspensions. The lack of teratoma or any ectopic tissue formation in the implanted rats bodes well for similar results with respect to safety in human subjects. PMID:23833067

  2. Expression and regulation of enzymes in the ceramide metabolic pathway in human retinal pigment epithelial cells and their relevance to retinal degeneration.

    Science.gov (United States)

    Zhu, DanHong; Sreekumar, Parameswaran G; Hinton, David R; Kannan, Ram

    2010-03-31

    Ceramide and its metabolic derivatives are important modulators of cellular apoptosis and proliferation. Dysregulation or imbalance of their metabolic pathways may promote the development of retinal degeneration. The aim of this study was to identify the expression and regulation of key enzymes of the ceramide pathway in retinal pigment epithelial (RPE) cells. RT-PCR was used to screen the enzymes involved in ceramide metabolism that are expressed in RPE. Over-expression of neutral sphingomyelinase-2 (SMPD3) or sphingosine kinase 1 (Sphk1) in ARPE-19 cells was achieved by transient transfection of SMPD3 or Sphk1 cDNA subcloned into an expression vector. The number of apoptotic or proliferating cells was determined using TUNEL and BrdU assays, respectively. Neutral sphingomyelinase-1, neutral sphingomyelinase-2, acidic ceramidase, ceramide kinase, SphK1 and Sphk2 were expressed in both ARPE-19 and early passage human fetal RPE (fRPE) cells, while alkaline ceramidase 2 was only expressed in fRPE cells. Over-expression of SMPD3 decreased RPE cell proliferation and increased cell apoptosis. The percentage of apoptotic cells increased proportionally with the amount of transfected SMPD3 DNA. Over-expression of SphK1 promoted cell proliferation and protected ARPE-19 cells from ceramide-induced apoptosis. The effect of C(2) ceramide on induction of apoptosis was evaluated in polarized vs. non-polarized RPE cultures; polarization of RPE was associated with much reduced apoptosis in response to ceramide. In conclusion, RPE cells possess the synthetic machinery for the production of ceramide, sphingosine, ceramide-1-phosphate (C1P), and sphingosine-1-phosphate (S1P). Over-expression of SMPD3 may increase cellular ceramide levels, leading to enhanced cell death and arrested cell proliferation. The selective induction of apoptosis in non-polarized RPE cultures by C(2) ceramide suggests that increased ceramide levels will preferentially affect non-polarized RPE, as are found in

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

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    Karen G Shadrach

    Full Text Available 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.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.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.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 stress is a known factor affecting this disease.

  4. Poly(trimethylene carbonate) as an elastic biodegradable film for human embryonic stem cell-derived retinal pigment epithelial cells

    NARCIS (Netherlands)

    Sorkio, Anni; Haimi, Suvi; Verdoold, Vincent; Juuti-Uusitalo, Kati; Grijpma, Dirk; Skottman, Heli

    2017-01-01

    Human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cell therapies show tremendous potential for the treatment of retinal degenerative diseases. A tissue engineering approach, where cells are delivered to the subretinal space on a biodegradable carrier as a sheet, shows great

  5. Poly(trimethylene carbonate) as an elastic biodegradable film for human embryonic stem cell-derived retinal pigment epithelial cells

    NARCIS (Netherlands)

    Sorkio, Anni; Haimi, Suvi; Verdoold, Vincent; Juuti-Uusitalo, Kati; Grijpma, Dirk; Skottman, Heli

    Human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cell therapies show tremendous potential for the treatment of retinal degenerative diseases. A tissue engineering approach, where cells are delivered to the subretinal space on a biodegradable carrier as a sheet, shows great

  6. Human embryonic stem cell-derived cells rescue visual function in dystrophic RCS rats.

    Science.gov (United States)

    Lund, Raymond D; Wang, Shaomei; Klimanskaya, Irina; Holmes, Toby; Ramos-Kelsey, Rebeca; Lu, Bin; Girman, Sergej; Bischoff, N; Sauvé, Yves; Lanza, Robert

    2006-01-01

    Embryonic stem cells promise to provide a well-characterized and reproducible source of replacement tissue for human clinical studies. An early potential application of this technology is the use of retinal pigment epithelium (RPE) for the treatment of retinal degenerative diseases such as macular degeneration. Here we show the reproducible generation of RPE (67 passageable cultures established from 18 different hES cell lines); batches of RPE derived from NIH-approved hES cells (H9) were tested and shown capable of extensive photoreceptor rescue in an animal model of retinal disease, the Royal College of Surgeons (RCS) rat, in which photoreceptor loss is caused by a defect in the adjacent retinal pigment epithelium. Improvement in visual performance was 100% over untreated controls (spatial acuity was approximately 70% that of normal nondystrophic rats) without evidence of untoward pathology. The use of somatic cell nuclear transfer (SCNT) and/or the creation of banks of reduced complexity human leucocyte antigen (HLA) hES-RPE lines could minimize or eliminate the need for immunosuppressive drugs and/or immunomodulatory protocols.

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

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    Alvaro Plaza Reyes

    2016-01-01

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

  8. Biological effects of cigarette smoke in cultured human retinal pigment epithelial cells.

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    Alice L Yu

    Full Text Available The goal of the present study was to determine whether treatment with cigarette smoke extract (CSE induces cell loss, cellular senescence, and extracellular matrix (ECM synthesis in primary human retinal pigment epithelial (RPE cells. Primary cultured human RPE cells were exposed to 2, 4, 8, and 12% of CSE concentration for 24 hours. Cell loss was detected by cell viability assay. Lipid peroxidation was assessed by loss of cis-parinaric acid (PNA fluorescence. Senescence-associated ß-galactosidase (SA-ß-Gal activity was detected by histochemical staining. Expression of apolipoprotein J (Apo J, connective tissue growth factor (CTGF, fibronectin, and laminin were examined by real-time PCR, western blot, or ELISA experiments. The results showed that exposure of cells to 12% of CSE concentration induced cell death, while treatment of cells with 2, 4, and 8% CSE increased lipid peroxidation. Exposure to 8% of CSE markedly increased the number of SA-ß-Gal positive cells to up to 82%, and the mRNA expression of Apo J, CTGF, and fibronectin by approximately 3-4 fold. Treatment with 8% of CSE also increased the protein expression of Apo J and CTGF and the secretion of fibronectin and laminin. Thus, treatment with CSE can induce cell loss, senescent changes, and ECM synthesis in primary human RPE cells. It may be speculated that cigarette smoke could be involved in cellular events in RPE cells as seen in age-related macular degeneration.

  9. Vitreous-induced cytoskeletal rearrangements via the Rac1 GTPase-dependent signaling pathway in human retinal pigment epithelial cells

    International Nuclear Information System (INIS)

    Huang, Xionggao; Wei, Yantao; Ma, Haizhi; Zhang, Shaochong

    2012-01-01

    Highlights: ► Vitreous induces morphological changes and cytoskeletal rearrangements in RPE cells. ► Rac1 is activated in vitreous-transformed RPE cells. ► Rac inhibition prevents morphological changes in vitreous-transformed RPE cells. ► Rac inhibition suppresses cytoskeletal rearrangements in vitreous-transformed RPE cells. ► The vitreous-induced effects are mediated by a Rac1 GTPase/LIMK1/cofilin pathway. -- Abstract: Proliferative vitreoretinopathy (PVR) is mainly caused by retinal pigment epithelial (RPE) cell migration, invasion, proliferation and transformation into fibroblast-like cells that produce the extracellular matrix (ECM). The vitreous humor is known to play an important role in PVR. An epithelial-to-mesenchymal transdifferentiation (EMT) of human RPE cells induced by 25% vitreous treatment has been linked to stimulation of the mesenchymal phenotype, migration and invasion. Here, we characterized the effects of the vitreous on the cell morphology and cytoskeleton in human RPE cells. The signaling pathway that mediates these effects was investigated. Serum-starved RPE cells were incubated with 25% vitreous, and the morphological changes were examined by phase-contrast microscopy. Filamentous actin (F-actin) was examined by immunofluorescence and confocal microscopy. Protein phosphorylation of AKT, ERK1/2, Smad2/3, LIM kinase (LIMK) 1 and cofilin was analyzed by Western blot analysis. Vitreous treatment induced cytoskeletal rearrangements, activated Rac1 and enhanced the phosphorylation of AKT, ERK1/2 and Smad2/3. When the cells were treated with a Rac activation-specific inhibitor, the cytoskeletal rearrangements were prevented, and the phosphorylation of Smad2/3 was blocked. Vitreous treatment also enhanced the phosphorylation of LIMK1 and cofilin and the Rac inhibitor blocked this effect. We propose that vitreous-transformed human RPE cells undergo cytoskeletal rearrangements via Rac1 GTPase-dependent pathways that modulate LIMK1 and

  10. Vitreous-induced cytoskeletal rearrangements via the Rac1 GTPase-dependent signaling pathway in human retinal pigment epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xionggao [State Key Ophthalmic Laboratory, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou (China); Department of Ophthalmology, Hainan Medical College, Haikou (China); Wei, Yantao; Ma, Haizhi [State Key Ophthalmic Laboratory, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou (China); Zhang, Shaochong, E-mail: zhshaochong@163.com [State Key Ophthalmic Laboratory, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou (China)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer Vitreous induces morphological changes and cytoskeletal rearrangements in RPE cells. Black-Right-Pointing-Pointer Rac1 is activated in vitreous-transformed RPE cells. Black-Right-Pointing-Pointer Rac inhibition prevents morphological changes in vitreous-transformed RPE cells. Black-Right-Pointing-Pointer Rac inhibition suppresses cytoskeletal rearrangements in vitreous-transformed RPE cells. Black-Right-Pointing-Pointer The vitreous-induced effects are mediated by a Rac1 GTPase/LIMK1/cofilin pathway. -- Abstract: Proliferative vitreoretinopathy (PVR) is mainly caused by retinal pigment epithelial (RPE) cell migration, invasion, proliferation and transformation into fibroblast-like cells that produce the extracellular matrix (ECM). The vitreous humor is known to play an important role in PVR. An epithelial-to-mesenchymal transdifferentiation (EMT) of human RPE cells induced by 25% vitreous treatment has been linked to stimulation of the mesenchymal phenotype, migration and invasion. Here, we characterized the effects of the vitreous on the cell morphology and cytoskeleton in human RPE cells. The signaling pathway that mediates these effects was investigated. Serum-starved RPE cells were incubated with 25% vitreous, and the morphological changes were examined by phase-contrast microscopy. Filamentous actin (F-actin) was examined by immunofluorescence and confocal microscopy. Protein phosphorylation of AKT, ERK1/2, Smad2/3, LIM kinase (LIMK) 1 and cofilin was analyzed by Western blot analysis. Vitreous treatment induced cytoskeletal rearrangements, activated Rac1 and enhanced the phosphorylation of AKT, ERK1/2 and Smad2/3. When the cells were treated with a Rac activation-specific inhibitor, the cytoskeletal rearrangements were prevented, and the phosphorylation of Smad2/3 was blocked. Vitreous treatment also enhanced the phosphorylation of LIMK1 and cofilin and the Rac inhibitor blocked this effect. We propose that vitreous

  11. 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...

  12. Analysis of the RPE sheet in the rd10 retinal degeneration model

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Yi [Los Alamos National Laboratory

    2011-01-04

    The normal RPE sheet in the C57Bl/6J mouse is subclassified into two major tiling patterns: A regular generally hexagonal array covering most of the surface and a 'soft network' near the ciliary body made of irregularly shaped cells. Physics models predict these two patterns based on contractility and elasticity of the RPE cell, and strength of cellular adhesion between cells. We hypothesized and identified major changes in RPE regular hexagonal tiling pattern in rdl0 compared to C57BL/6J mice. RPE sheet damage was extensive but occurred in rd10 later than expected, after most retinal degeneration. RPE sheet changes occur in zones with a bullseye pattern. In the posterior zone around the optic nerve RPE cells take on larger irregular and varied shapes to form an intact monolayer. In mid periphery, there is a higher than normal density of cells that progress into involuted layers of RPE under the retina. The periphery remains mostly normal until late stages of degeneration. The number of neighboring cells varies widely depending on zone and progression. RPE morphology continues to deteriorate long after the photoreceptors have degenerated. The RPE cells are bystanders to the rd10 degeneration within photo receptors, and the collateral damage to the RPE sheet resembles stimulation of migration or chemotaxis. Quantitative measures of the tiling patterns and histopathology detected here, scripted in a pipeline written in Perl and Cell Profiler (an open source Matlab plugin), are directly applicable to RPE sheet images from noninvasive fundus autofluorescence (FAF), adaptive optics confocal scanning laser ophthalmoscope (AO-cSLO), and spectral domain optical coherence tomography (SD-OCT) of patients with early stage AMD or RP.

  13. X-ray microprobe analysis of the retina and RPE in sheep with ovine ceroid-lipofuscinosis

    International Nuclear Information System (INIS)

    Samuelson, D.A.; Armstrong, D.; Jolly, R.

    1990-01-01

    Ovine ceroid-lipofuscinosis (OCL) is one animal model for the human condition, and because autofluorescent lipopigments are prominent in the brain and eye, it may also prove useful as a model for aging. For example, a progressive decline in electrical recording from brain and retina are observed in both aging and OCL. Samples of retinal and retinal pigment epithelial (RPE) tissues were obtained from a young control. 2 animals with OCL and a normal aged sheep. Specimens were cryo-fractured and examined by scanning electron microscopy/x-ray microanalysis. Measurements made of 6 individual cells in the ganglion layer of OCL specimens, the remainder of the retina, and RPE showed age-related changes in zinc, iron, and copper which were associated with lipopigment accumulation in the RPE. There was marked decrease in phosphate, sulfur, and manganese levels, as photoreceptor cells and their outer segments are lost in the disease process. This is the first report of metal analysis in the retina and RPE in a disease entity, and as a function of normal aging

  14. Multi-nucleate retinal pigment epithelium cells of the human macula exhibit a characteristic and highly specific distribution.

    Science.gov (United States)

    Starnes, Austin C; Huisingh, Carrie; McGwin, Gerald; Sloan, Kenneth R; Ablonczy, Zsolt; Smith, R Theodore; Curcio, Christine A; Ach, Thomas

    2016-01-01

    The human retinal pigment epithelium (RPE) is reportedly 3% bi-nucleated. The importance to human vision of multi-nucleated (MN)-RPE cells could be clarified with more data about their distribution in central retina. Nineteen human RPE-flatmounts (9 ≤ 51 years, 10 > 80 years) were imaged at 12 locations: 3 eccentricities (fovea, perifovea, near periphery) in 4 quadrants (superior, inferior, temporal, nasal). Image stacks of lipofuscin-attributable autofluorescence and phalloidin labeled F-actin cytoskeleton were obtained using a confocal fluorescence microscope. Nuclei were devoid of autofluorescence and were marked using morphometric software. Cell areas were approximated by Voronoi regions. Mean number of nuclei per cell among eccentricity/quadrant groups and by age were compared using Poisson and binominal regression models. A total of 11,403 RPE cells at 200 locations were analyzed: 94.66% mono-, 5.31% bi-, 0.02% tri-nucleate, and 0.01% with 5 nuclei. Age had no effect on number of nuclei. There were significant regional differences: highest frequencies of MN-cells were found at the perifovea (9.9%) and near periphery (6.8%). The fovea lacked MN-cells almost entirely. The nasal quadrant had significantly more MN-cells compared to other quadrants, at all eccentricities. This study demonstrates MN-RPE cells in human macula. MN-cells may arise due to endoreplication, cell fusion, or incomplete cell division. The topography of MN-RPE cells follows the topography of photoreceptors; with near-absence at the fovea (cones only) and high frequency at perifovea (highest rod density). This distribution might reflect specific requirements of retinal metabolism or other mechanisms addressable in further studies.

  15. Chemokine Expression in Retinal Pigment Epithelial ARPE-19 Cells in Response to Coculture with Activated T Cells

    DEFF Research Database (Denmark)

    Juel, Helene Bæk; Faber, Carsten; Udsen, Maja

    2012-01-01

    Purpose. To investigate the effects of T-cell–derived cytokines on gene and protein expression of chemokines in a human RPE cell line (ARPE-19). Methods. We used an in vitro coculture system in which the RPE and CD3/CD28–activated T-cells were separated by a membrane. RPE cell expression of chemo......Purpose. To investigate the effects of T-cell–derived cytokines on gene and protein expression of chemokines in a human RPE cell line (ARPE-19). Methods. We used an in vitro coculture system in which the RPE and CD3/CD28–activated T-cells were separated by a membrane. RPE cell expression...

  16. The influences of purple sweet potato anthocyanin on the growth characteristics of human retinal pigment epithelial cells

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    Min Sun

    2015-06-01

    Full Text Available Background: Anthocyanins have been proven to be beneficial to the eyes. However, information is scarce about the effects of purple sweet potato (Ipomoea batatas, L. anthocyanin (PSPA, a class of anthocyanins derived from purple sweet potato roots, on visual health. Objective: The aim of this study was to investigate whether PSPA could have influences on the growth characteristics (cellular morphology, survival, and proliferation of human retinal pigment epithelial (RPE cells, which perform essential functions for the visual process. Methods: The RPE cell line D407 was used in the present study. The cytotoxicity of PSPA was assessed by MTT assay. Then, cellular morphology, viability, cell cycle, Ki67expression, and PI3K/MAPK activation of RPE cells treated with PSPA were determined. Results: PSPA exhibited dose-dependent promotion of RPE cell proliferation at concentrations ranging from 10 to 1,000 µg/ml. RPE cells treated with PSPA demonstrated a predominantly polygonal morphology in a mosaic arrangement, and colony-like cells displayed numerous short apical microvilli and typical ultrastructure. PSPA treatment also resulted in a better platform growing status, statistically higher viability, an increase in the S-phase, and more Ki67+ cells. However, neither pAkt nor pERK were detected in either group. Conclusions: We found that PSPA maintained high cell viability, boosted DNA synthesis, and preserved a high percentage of continuously cycling cells to promote cell survival and division without changing cell morphology. This paper lays the foundation for further research about the damage-protective activities of PSPA on RPE cells or human vision.

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

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    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.

  18. TNF-α mediates choroidal neovascularization by upregulating VEGF expression in RPE through ROS-dependent β-catenin activation.

    Science.gov (United States)

    Wang, Haibo; Han, Xiaokun; Wittchen, Erika S; Hartnett, M Elizabeth

    2016-01-01

    Inflammation, oxidative stress, and angiogenesis have been proposed to interact in age-related macular degeneration. It has been postulated that external stimuli that cause oxidative stress can increase production of vascular endothelial growth factor (VEGF) in retinal pigment epithelial (RPE) cells. In this study, we tested the hypothesis that the inflammatory cytokine, tumor necrosis factor alpha (TNF-α), contributed to choroidal neovascularization (CNV) by upregulating VEGF in RPE through intracellular reactive oxygen species (ROS)-dependent signaling and sought to understand the mechanisms involved. In a murine laser-induced CNV model, 7 days after laser treatment and intravitreal neutralizing mouse TNF-α antibody or isotype immunoglobulin G (IgG) control, the following measurements were made: 1) TNF-α protein and VEGF protein in RPE/choroids with western blot, 2) CNV volume in RPE/choroidal flatmounts, and 3) semiquantification of oxidized phospholipids stained with E06 antibody within CNV with immunohistochemistry (IHC). In cultured human RPE cells treated with TNF-α or PBS control, 1) ROS generation was measured using the 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) fluorescence assay, and 2) NOX4 protein and VEGF protein or mRNA were measured with western blot or quantitative real-time PCR in cells pretreated with apocynin or nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) inhibitor, VAS 2870, or transfected with p22phox siRNA, and each was compared to its appropriate control. Western blots of phosphorylated p65 (p-p65), total p65 and β-actin, and quantitative real-time PCR of VEGF mRNA were measured in human RPE cells treated with TNF-α and pretreatment with the nuclear factor kappa B inhibitor, Bay 11-7082 or control. Western blots of β-catenin, VEGF, and p22phox and coimmunoprecipitation of β-catenin and T-cell transcriptional factor were performed in human RPE cells treated with TNF-α following pretreatment with

  19. Role of macrophage migration inhibitory factor (MIF) in the effects of oxidative stress on human retinal pigment epithelial cells.

    Science.gov (United States)

    Ko, Ji-Ae; Sotani, Yasuyuki; Ibrahim, Diah Gemala; Kiuchi, Yoshiaki

    2017-10-01

    Proliferative vitreoretinopathy (PVR) is the major cause of treatment failure in individuals who undergo surgery for retinal detachment. The epithelial-mesenchymal transition (EMT) in retinal pigment epithelium (RPE) cells contributes to the pathogenesis of PVR. Oxidative stress is thought to play a role in the progression of retinal diseases including PVR. We have now examined the effects of oxidative stress on the EMT and related processes in the human RPE cell line. We found that H 2 O 2 induced the contraction of RPE cells in a three-dimensional collagen gel. Analysis of a cytokine array revealed that H 2 O 2 specifically increased the release of macrophage migration inhibitory factor (MIF) from RPE cells. Reverse transcription-polymerase chain reaction and immunoblot analyses showed that H 2 O 2 increased the expression of MIF in RPE cells. Immunoblot and immunofluorescence analyses revealed that H 2 O 2 upregulated the expression of α-SMA and vimentin and downregulated that of ZO-1 and N-cadherin. Consistent with these observations, the transepithelial electrical resistance of cell was reduced by exposure to H 2 O 2 . The effects of oxidative stress on EMT-related and junctional protein expression as well as on transepithelial electrical resistance were inhibited by antibodies to MIF, but they were not mimicked by treatment with recombinant MIF. Finally, analysis with a profiling array for mitogen-activated protein kinase signalling revealed that H 2 O 2 specifically induced the phosphorylation of p38 mitogen-activated protein kinase. Our results thus suggest that MIF may play a role in induction of the EMT and related processes by oxidative stress in RPE cells and that it might thereby contribute to the pathogenesis of PVR. Proliferative vitreoretinopathy is a major complication of rhegmatogenous retinal detachment, and both oxidative stress and induction of the EMT in RPE cells are thought to contribute to the pathogenesis of this condition. We have now

  20. Intracameral voriconazole: In vitro safety for human ocular cells

    International Nuclear Information System (INIS)

    Kernt, M.; Kampik, A.

    2009-01-01

    Fungal keratitis is a sight-threatening infection of the cornea. It sometimes leads to loss of the eye. Despite an expanding range of fungal pathogens, there are only few therapeutic agents for its treatment available. Voriconazole is a second-generation synthetic triazole with a broad action against yeasts and molds. The current study investigates the safety of voriconazole for intracameral application in a cell culture model. Endothelial toxicity of voriconazole was evaluated in cultured human corneas. Possible toxic effects of voriconazole (10 μg/mL-10 mg/mL) in corneal endothelial cells (CEC), primary human trabecular meshwork cells (TMC), and primary human retinal pigment epithelium (RPE) cells were evaluated after 24 h and under conditions of inflammatory stress by treatment with tumor-necrosis-factor alpha (TNF-α), lipopolysaccharides (LPS), or interleukin-6 (IL-6) and hydrogen peroxide. Toxicity was evaluated by tetrazolium dye-reduction assay, and cell viability was quantified by a microscopic live-dead assay. No corneal endothelial toxicity could be detected after 30 days of treatment with 250 μg/mL of voriconazole. Concentrations up to 1 mg/mL had no influence on CEC, TMC, or RPE cell proliferation, or on cell viability when administered for 24 h. Hydrogen peroxide exposure did not increase cellular toxicity of voriconazole at concentrations from 10 to 250 μg/mL. After preincubation with TNF-α, LPS, or IL-6 for 24 h and subsequent voriconazole treatment for 24 h, no significant decrease in proliferation or viability was observed. This study showed no significant toxicity for voriconazole on CEC, TMC, RPE cells, or human corneal endothelium when administered in therapeutic concentrations up to 250 μg/mL

  1. Survival and Functionality of hESC-Derived Retinal Pigment Epithelium Cells Cultured as a Monolayer on Polymer Substrates Transplanted in RCS Rats.

    Science.gov (United States)

    Thomas, Biju B; Zhu, Danhong; Zhang, Li; Thomas, Padmaja B; Hu, Yuntao; Nazari, Hossein; Stefanini, Francisco; Falabella, Paulo; Clegg, Dennis O; Hinton, David R; Humayun, Mark S

    2016-05-01

    To determine the safety, survival, and functionality of human embryonic stem cell-derived RPE (hESC-RPE) cells seeded on a polymeric substrate (rCPCB-RPE1 implant) and implanted into the subretinal (SR) space of Royal College of Surgeons (RCS) rats. Monolayers of hESC-RPE cells cultured on parylene membrane were transplanted into the SR space of 4-week-old RCS rats. Group 1 (n = 46) received vitronectin-coated parylene membrane without cells (rMSPM+VN), group 2 (n = 59) received rCPCB-RPE1 implants, and group 3 (n = 13) served as the control group. Animals that are selected based on optical coherence tomography screening were subjected to visual function assays using optokinetic (OKN) testing and superior colliculus (SC) electrophysiology. At approximately 25 weeks of age (21 weeks after surgery), the eyes were examined histologically for cell survival, phagocytosis, and local toxicity. Eighty-seven percent of the rCPCB-RPE1-implanted animals showed hESC-RPE survivability. Significant numbers of outer nuclear layer cells were rescued in both group 1 (rMSPM+VN) and group 2 (rCPCB-RPE1) animals. A significantly higher ratio of rod photoreceptor cells to cone photoreceptor cells was found in the rCPCB-RPE1-implanted group. Animals with rCPCB-RPE1 implant showed hESC-RPE cells containing rhodopsin-positive particles in immunohistochemistry, suggesting phagocytic function. Superior colliculus mapping data demonstrated that a significantly higher number of SC sites responded to light stimulus at a lower luminance threshold level in the rCPCB-RPE1-implanted group. Optokinetic data suggested both implantation groups showed improved visual acuity. These results demonstrate the safety, survival, and functionality of the hESC-RPE monolayer transplantation in an RPE dysfunction rat model.

  2. 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.

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

    Science.gov (United States)

    Sanie-Jahromi, Fatemeh; Ahmadieh, Hamid; Soheili, Zahra-Soheila; Davari, Maliheh; Ghaderi, Shima; Kanavi, Mozhgan Rezaei; Samiei, Shahram; Deezagi, Abdolkhalegh; Pakravesh, Jalil; Bagheri, Abouzar

    2012-04-10

    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. 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. 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.

  4. 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.

  5. N-Acetylcysteine Amide Protects Against Oxidative Stress–Induced Microparticle Release From Human Retinal Pigment Epithelial Cells

    Science.gov (United States)

    Carver, Kyle A.; Yang, Dongli

    2016-01-01

    Purpose Oxidative stress is a major factor involved in retinal pigment epithelium (RPE) apoptosis that underlies AMD. Drusen, extracellular lipid- and protein-containing deposits, are strongly associated with the development of AMD. Cell-derived microparticles (MPs) are small membrane-bound vesicles shed from cells. The purpose of this study was to determine if oxidative stress drives MP release from RPE cells, to assess whether these MPs carry membrane complement regulatory proteins (mCRPs: CD46, CD55, and CD59), and to evaluate the effects of a thiol antioxidant on oxidative stress–induced MP release. Methods Retinal pigment epithelium cells isolated from human donor eyes were cultured and treated with hydrogen peroxide (H2O2) to induce oxidative stress. Isolated MPs were fixed for transmission electron microscopy or processed for component analysis by flow cytometry, Western blot analysis, and confocal microscopy. Results Transmission electron microscopy showed that MPs ranged in diameter from 100 to 1000 nm. H2O2 treatment led to time- and dose-dependent elevations in MPs with externalized phosphatidylserine and phosphatidylethanolamine, known markers of MPs. These increases were strongly correlated to RPE apoptosis. Oxidative stress significantly increased the release of mCRP-positive MPs, which were prevented by a thiol antioxidant, N-acetylcysteine amide (NACA). Conclusions This is the first evidence that oxidative stress induces cultured human RPE cells to release MPs that carry mCRPs on their surface. The levels of released MPs are strongly correlated with RPE apoptosis. N-acetylcysteine amide prevents oxidative stress–induced effects. Our findings indicate that oxidative stress reduces mCRPs on the RPE surface through releasing MPs. PMID:26842754

  6. Targeted siRNA Screens Identify ER-to-Mitochondrial Calcium Exchange in Autophagy and Mitophagy Responses in RPE1 Cells

    Directory of Open Access Journals (Sweden)

    Thomas D. B. MacVicar

    2015-06-01

    Full Text Available Autophagy is an important stress response pathway responsible for the removal and recycling of damaged or redundant cytosolic constituents. Mitochondrial damage triggers selective mitochondrial autophagy (mitophagy, mediated by a variety of response factors including the Pink1/Parkin system. Using human retinal pigment epithelial cells stably expressing autophagy and mitophagy reporters, we have conducted parallel screens of regulators of endoplasmic reticulum (ER and mitochondrial morphology and function contributing to starvation-induced autophagy and damage-induced mitophagy. These screens identified the ER chaperone and Ca2+ flux modulator, sigma non-opioid intracellular receptor 1 (SIGMAR1, as a regulator of autophagosome expansion during starvation. Screens also identified phosphatidyl ethanolamine methyl transferase (PEMT and the IP3-receptors (IP3Rs as mediators of Parkin-induced mitophagy. Further experiments suggested that IP3R-mediated transfer of Ca2+ from the ER lumen to the mitochondrial matrix via the mitochondrial Ca2+ uniporter (MCU primes mitochondria for mitophagy. Importantly, recruitment of Parkin to damaged mitochondria did not require IP3R-mediated ER-to-mitochondrial Ca2+ transfer, but mitochondrial clustering downstream of Parkin recruitment was impaired, suggesting involvement of regulators of mitochondrial dynamics and/or transport. Our data suggest that Ca2+ flux between ER and mitochondria at presumed ER/mitochondrial contact sites is needed both for starvation-induced autophagy and for Parkin-mediated mitophagy, further highlighting the importance of inter-organellar communication for effective cellular homeostasis.

  7. Differential behavioral outcomes following neonatal versus fetal human retinal pigment epithelial cell striatal implants in parkinsonian rats

    DEFF Research Database (Denmark)

    Russ, Kaspar; Flores, Joseph; Brudek, Tomasz

    2017-01-01

    Following the failure of a Phase II clinical study evaluating human retinal pigment epithelial (hRPE) cell implants as a potential treatment option for Parkinson's disease, speculation has centered on implant function and survival as possible contributors to the therapeutic outcomes. We recently ...

  8. Three-dimensional neuroepithelial culture from human embryonic stem cells and its use for quantitative conversion to retinal pigment epithelium.

    Directory of Open Access Journals (Sweden)

    Yu Zhu

    Full Text Available A goal in human embryonic stem cell (hESC research is the faithful differentiation to given cell types such as neural lineages. During embryonic development, a basement membrane surrounds the neural plate that forms a tight, apico-basolaterally polarized epithelium before closing to form a neural tube with a single lumen. Here we show that the three-dimensional epithelial cyst culture of hESCs in Matrigel combined with neural induction results in a quantitative conversion into neuroepithelial cysts containing a single lumen. Cells attain a defined neuroepithelial identity by 5 days. The neuroepithelial cysts naturally generate retinal epithelium, in part due to IGF-1/insulin signaling. We demonstrate the utility of this epithelial culture approach by achieving a quantitative production of retinal pigment epithelial (RPE cells from hESCs within 30 days. Direct transplantation of this RPE into a rat model of retinal degeneration without any selection or expansion of the cells results in the formation of a donor-derived RPE monolayer that rescues photoreceptor cells. The cyst method for neuroepithelial differentiation of pluripotent stem cells is not only of importance for RPE generation but will also be relevant to the production of other neuronal cell types and for reconstituting complex patterning events from three-dimensional neuroepithelia.

  9. Controlled surface morphology and hydrophilicity of polycaprolactone toward human retinal pigment epithelium cells

    International Nuclear Information System (INIS)

    Shahmoradi, Saleheh; Yazdian, Fatemeh; Tabandeh, Fatemeh; Soheili, Zahra-Soheila; Hatamian Zarami, Ashraf Sadat; Navaei-Nigjeh, Mona

    2017-01-01

    Applying scaffolds as a bed to enhance cell proliferation and even differentiation is one of the treatment of retina diseases such as age-related macular degeneration (AMD) which deteriorating photoreceptors and finally happening blindness. In this study, aligned polycaprolactone (PCL) nanofibers were electrospun and at different conditions and their characteristics were measured by scanning electron microscope (SEM) and contact angle. Response surface methodology (RSM) was used to optimize the diameter of fabricated nanofibers. Two factors as solution concentration and voltage value were considered as independent variables and their effects on nanofibers' diameters were evaluated by central composite design and the optimum conditions were obtained as 0.12 g/mL and 20 kV, respectively. In order to decrease the hydrophobicity of PCL, the surface of the fabricated scaffolds was modified by alkaline hydrolysis method. Contact time of the scaffolds and alkaline solution and concentration of alkaline solution were optimized using Box Behnken design and (120 min and 5 M were the optimal, respectively). Contact angle measurement showed the high hydrophilicity of treated scaffolds (with contact angle 7.48°). Plasma surface treatment was applied to compare the effect of using two kinds of surface modification methods simultaneously on hydrolyzed scaffolds. The RPE cells grown on scaffolds were examined by immunocytochemistry (ICC), MTT and continuous inspection of cellular morphology. Interestingly, Human RPE cells revealed their characteristic morphology on hydrolyzed scaffold well. As a result, we introduced a culture substrate with low diameter (185.8 nm), high porosity (82%) and suitable hydrophilicity (with contact angle 7.48 degree) which can be promising for hRPE cell transplantation. - Highlights: • Dimethylformamide (DMF) has significant effect on reduction of fibers' diameter. • Having high hydrophilicity by alkaline hydrolysis • Suitable

  10. Controlled surface morphology and hydrophilicity of polycaprolactone toward human retinal pigment epithelium cells

    Energy Technology Data Exchange (ETDEWEB)

    Shahmoradi, Saleheh; Yazdian, Fatemeh [Department of Life Science Engineering, Faculty of New sciences and Technologies, University of Tehran, Tehran (Iran, Islamic Republic of); Tabandeh, Fatemeh, E-mail: taban_f@nigeb.ac.ir [Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran (Iran, Islamic Republic of); Soheili, Zahra-Soheila [Department of Molecular Medicine, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran (Iran, Islamic Republic of); Hatamian Zarami, Ashraf Sadat [Department of Life Science Engineering, Faculty of New sciences and Technologies, University of Tehran, Tehran (Iran, Islamic Republic of); Navaei-Nigjeh, Mona [Department of Tissue Engineering, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2017-04-01

    Applying scaffolds as a bed to enhance cell proliferation and even differentiation is one of the treatment of retina diseases such as age-related macular degeneration (AMD) which deteriorating photoreceptors and finally happening blindness. In this study, aligned polycaprolactone (PCL) nanofibers were electrospun and at different conditions and their characteristics were measured by scanning electron microscope (SEM) and contact angle. Response surface methodology (RSM) was used to optimize the diameter of fabricated nanofibers. Two factors as solution concentration and voltage value were considered as independent variables and their effects on nanofibers' diameters were evaluated by central composite design and the optimum conditions were obtained as 0.12 g/mL and 20 kV, respectively. In order to decrease the hydrophobicity of PCL, the surface of the fabricated scaffolds was modified by alkaline hydrolysis method. Contact time of the scaffolds and alkaline solution and concentration of alkaline solution were optimized using Box Behnken design and (120 min and 5 M were the optimal, respectively). Contact angle measurement showed the high hydrophilicity of treated scaffolds (with contact angle 7.48°). Plasma surface treatment was applied to compare the effect of using two kinds of surface modification methods simultaneously on hydrolyzed scaffolds. The RPE cells grown on scaffolds were examined by immunocytochemistry (ICC), MTT and continuous inspection of cellular morphology. Interestingly, Human RPE cells revealed their characteristic morphology on hydrolyzed scaffold well. As a result, we introduced a culture substrate with low diameter (185.8 nm), high porosity (82%) and suitable hydrophilicity (with contact angle 7.48 degree) which can be promising for hRPE cell transplantation. - Highlights: • Dimethylformamide (DMF) has significant effect on reduction of fibers' diameter. • Having high hydrophilicity by alkaline hydrolysis • Suitable

  11. Fundus albipunctatus associated with compound heterozygous mutations in RPE65

    DEFF Research Database (Denmark)

    Schatz, Patrik; Preising, Markus; Lorenz, Birgit

    2011-01-01

    To describe a family with an 18-year-old woman with fundus albipunctatus and compound heterozygous mutations in RPE65 whose unaffected parents and 1 female sibling harbored single heterozygous RPE65 mutations.......To describe a family with an 18-year-old woman with fundus albipunctatus and compound heterozygous mutations in RPE65 whose unaffected parents and 1 female sibling harbored single heterozygous RPE65 mutations....

  12. Retinal pigment epithelium culture;a potential source of retinal stem cells.

    Science.gov (United States)

    Akrami, Hassan; Soheili, Zahra-Soheila; Khalooghi, Keynoush; Ahmadieh, Hamid; Rezaie-Kanavi, Mojgan; Samiei, Shahram; Davari, Malihe; Ghaderi, Shima; Sanie-Jahromi, Fatemeh

    2009-07-01

    To establish human retinal pigment epithelial (RPE) cell culture as a source for cell replacement therapy in ocular diseases. Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco's Modified Eagle's Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered.

  13. Construction of a cDNA library from human retinal pigment epithelial cells challenged with rod outer segments.

    Science.gov (United States)

    Cavaney, D M; Rakoczy, P E; Constable, I J

    1995-05-01

    To study genes expressed by retinal pigment epithelial (RPE) cells during phagocytosis and digestion of rod outer segments (ROS), a complementary (c)DNA library was produced using an in-vitro model. The cDNA library can be used to study molecular changes which contribute to the development of diseases due to a failure in outer segment phagocytosis and digestion by RPE cells. Here we demonstrate a way to study genes and their functions using a molecular biological approach and describing the first step involved in this process, the construction of a cDNA library. Human RPE cells obtained from the eyes of a seven-year-old donor were cultured and challenged with bovine ROS. The culture was harvested and total RNA was extracted. Complementary DNA was transcribed from the messenger (m)RNA and was directionally cloned into the LambdaGEM-4 bacteriophage vector successfully. Some clones were picked and the DNA extracted, to determine the size of the inserts as a measure of the quality of the library. Molecular biology and cell culture are important tools to be used in eye research, especially in areas where tissue is limiting and animal models are not available. We now have a ROS challenged RPE cDNA library which will be used to identify genes responsible for degrading phagocytosed debris within the retinal pigment epithelium.

  14. The Human Cell Atlas.

    Science.gov (United States)

    Regev, Aviv; Teichmann, Sarah A; Lander, Eric S; Amit, Ido; Benoist, Christophe; Birney, Ewan; Bodenmiller, Bernd; Campbell, Peter; Carninci, Piero; Clatworthy, Menna; Clevers, Hans; Deplancke, Bart; Dunham, Ian; Eberwine, James; Eils, Roland; Enard, Wolfgang; Farmer, Andrew; Fugger, Lars; Göttgens, Berthold; Hacohen, Nir; Haniffa, Muzlifah; Hemberg, Martin; Kim, Seung; Klenerman, Paul; Kriegstein, Arnold; Lein, Ed; Linnarsson, Sten; Lundberg, Emma; Lundeberg, Joakim; Majumder, Partha; Marioni, John C; Merad, Miriam; Mhlanga, Musa; Nawijn, Martijn; Netea, Mihai; Nolan, Garry; Pe'er, Dana; Phillipakis, Anthony; Ponting, Chris P; Quake, Stephen; Reik, Wolf; Rozenblatt-Rosen, Orit; Sanes, Joshua; Satija, Rahul; Schumacher, Ton N; Shalek, Alex; Shapiro, Ehud; Sharma, Padmanee; Shin, Jay W; Stegle, Oliver; Stratton, Michael; Stubbington, Michael J T; Theis, Fabian J; Uhlen, Matthias; van Oudenaarden, Alexander; Wagner, Allon; Watt, Fiona; Weissman, Jonathan; Wold, Barbara; Xavier, Ramnik; Yosef, Nir

    2017-12-05

    The recent advent of methods for high-throughput single-cell molecular profiling has catalyzed a growing sense in the scientific community that the time is ripe to complete the 150-year-old effort to identify all cell types in the human body. The Human Cell Atlas Project is an international collaborative effort that aims to define all human cell types in terms of distinctive molecular profiles (such as gene expression profiles) and to connect this information with classical cellular descriptions (such as location and morphology). An open comprehensive reference map of the molecular state of cells in healthy human tissues would propel the systematic study of physiological states, developmental trajectories, regulatory circuitry and interactions of cells, and also provide a framework for understanding cellular dysregulation in human disease. Here we describe the idea, its potential utility, early proofs-of-concept, and some design considerations for the Human Cell Atlas, including a commitment to open data, code, and community.

  15. 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.

  16. The human cell atlas

    DEFF Research Database (Denmark)

    Regev, Aviv; Teichmann, Sarah A.; Lander, Eric S.

    2017-01-01

    The recent advent of methods for high-throughput single-cell molecular profiling has catalyzed a growing sense in the scientific community that the time is ripe to complete the 150-year-old effort to identify all cell types in the human body. The Human Cell Atlas Project is an international...... collaborative effort that aims to define all human cell types in terms of distinctive molecular profiles (such as gene expression profiles) and to connect this information with classical cellular descriptions (such as location and morphology). An open comprehensive reference map of the molecular state of cells...... in healthy human tissues would propel the systematic study of physiological states, developmental trajectories, regulatory circuitry and interactions of cells, and also provide a framework for understanding cellular dysregulation in human disease. Here we describe the idea, its potential utility, early...

  17. Induced pluripotent stem cell-based therapy for age-related macular degeneration.

    Science.gov (United States)

    Bracha, Peter; Moore, Nicholas A; Ciulla, Thomas A

    2017-09-01

    In age-related macular degeneration (AMD), stem cells could possibly replace or regenerate disrupted pathologic retinal pigment epithelium (RPE), and produce supportive growth factors and cytokines such as brain-derived neurotrophic factor.  Induced pluripotent stem cells (iPSCs)-derived RPE was first subretinally transplanted in a neovascular AMD patient in 2014. Areas covered: Induced PSCs are derived from the introduction of transcription factors to adult cells under specific cell culture conditions, followed by differentiation into RPE cells. Induced PSC-derived RPE cells exhibit ion transport, membrane potential, polarized VEGF secretion and gene expression that is similar to native RPE. Despite having similar in vitro function, morphology, immunostaining and microscopic analysis, it remains to be seen if iPSC-derived RPE can replicate the myriad of in vivo functions, including immunomodulatory effects, of native RPE cells.  Historically, adjuvant RPE transplantation during CNV resections were technically difficult and complicated by immune rejection. Autologous iPSCs are hypothesized to reduce the risk of immune rejection, but their production is time-consuming and expensive.  Alternatively, allogenic transplantation using human leukocyte antigen (HLA)-matched iPSCs, similar to HLA-matched organ transplantation, is currently being investigated. Expert opinion: Challenges to successful transplantation with iPSCs include surgical technique, a pathologic subretinal microenvironment, possible immune rejection, and complications of immunosuppression.

  18. Progranulin increases phagocytosis by retinal pigment epithelial cells in culture.

    Science.gov (United States)

    Murase, Hiromi; Tsuruma, Kazuhiro; Kuse, Yoshiki; Shimazawa, Masamitsu; Hara, Hideaki

    2017-12-01

    Retinal pigment epithelium (RPE) cells take part in retinal preservation, such as phagocytizing the shed photoreceptor outer segments (POS), every day. The incomplete phagocytic function accelerates RPE degeneration and formation of the toxic by-product lipofuscin. Excessive lipofuscin accumulation is characteristic of various blinding diseases in the human eye. Progranulin is a cysteine-rich protein that has multiple biological activities, and it has a high presence in the retina. Progranulin has been recognized to be involved in macrophage phagocytosis in the brain. The purpose of this study is to determine whether progranulin influences phagocytosis by RPE cells. All experiments were performed on primary human RPE (hRPE) cells in culture. pHrodo was used to label the isolated porcine POS, and quantification of pHrodo fluorescence was used to determine the degree of phagocytosis. Western blotting and immunohistochemistry of key proteins involved in phagocytosis were used to clarify the mechanism of progranulin. Progranulin increased RPE phagocytosis in hydrogen peroxide-treated and nontreated RPE cells. The phosphorylated form of Mer tyrosine kinase, which is important for POS internalization, was significantly increased in the progranulin-exposed cells. This increase was attenuated by SU11274, an inhibitor of hepatic growth factor receptor. Under the oxidative stress condition, exposure to progranulin led to an approximately twofold increase in integrin alpha-v, which is associated with the first step in recognition of POS by RPE cells. These results suggest that progranulin could be an effective stimulator for RPE phagocytosis and could repair RPE function. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Mechanisms of selective delivery of xanthophylls to retinal pigment epithelial cells by human lipoproteins.

    Science.gov (United States)

    Thomas, Sara E; Harrison, Earl H

    2016-10-01

    The xanthophylls, lutein and zeaxanthin, are dietary carotenoids that selectively accumulate in the macula of the eye providing protection against age-related macular degeneration. To reach the macula, carotenoids cross the retinal pigment epithelium (RPE). Xanthophylls and β-carotene mostly associate with HDL and LDL, respectively. HDL binds to cells via a scavenger receptor class B1 (SR-B1)-dependent mechanism, while LDL binds via the LDL receptor. Using an in-vitro, human RPE cell model (ARPE-19), we studied the mechanisms of carotenoid uptake into the RPE by evaluating kinetics of cell uptake when delivered in serum or isolated LDL or HDL. For lutein and β-carotene, LDL delivery resulted in the highest rates and extents of uptake. In contrast, HDL was more effective in delivering zeaxanthin and meso-zeaxanthin leading to the highest rates and extents of uptake of all four carotenoids. Inhibitors of SR-B1 suppressed zeaxanthin delivery via HDL. Results show a selective HDL-mediated uptake of zeaxanthin and meso-zeaxanthin via SR-B1 and a LDL-mediated uptake of lutein. This demonstrates a plausible mechanism for the selective accumulation of zeaxanthin greater than lutein and xanthophylls over β-carotene in the retina. We found no evidence of xanthophyll metabolism to apocarotenoids or lutein conversion to meso-zeaxanthin. Copyright © 2016 by the American Society for Biochemistry and Molecular Biology, Inc.

  20. Resveratrol Protects Against Ultraviolet A-Mediated Inhibition of the Phagocytic Function of Human Retinal Pigment Epithelial Cells Via Large-Conductance Calcium-Activated Potassium Channels

    Directory of Open Access Journals (Sweden)

    Shwu-Jiuan Sheu

    2009-07-01

    Full Text Available This study was undertaken to examine the protective effect of resveratrol on human retinal pigment epithelial (RPE cell phagocytosis against ultraviolet irradiation damage. Cultured RPE cells were exposed to ultraviolet A (UVA, 20 minutes irradiation, and treated with meclofenamic acid (30μM, 20 minutes, paxilline (100 μM, 20 minutes or resveratrol (10μM, 20 minutes. Meclofenamic acid and resveratrol were given after exposure to UVA. Pretreatment with meclofenamic acid, resveratrol or paxilline before UVA irradiation was also performed. Fluorescent latex beads were then fed for 4 hours and the phagocytotic function was assessed by flow cytometry. UVA irradiation inhibited the phagocytic function of human RPE cells. The large-conductance calcium-activated potassium channel activator meclofenamic acid ameliorated the damage caused by UVA irradiation. Pretreatment with resveratrol acid also provided protection against damage caused by UVA. Posttreatment with meclofenamic acid offered mild protection, whereas resveratrol did not. In conclusion, the red wine flavonoid resveratrol ameliorated UVA-mediated inhibition of human RPE phagocytosis. The underlying mechanism might involve the large-conductance calcium-activated potassium channels.

  1. Role for nectin-1 in herpes simplex virus 1 entry and spread in human retinal pigment epithelial cells

    Science.gov (United States)

    Tiwari, Vaibhav; Oh, Myung-Jin; Kovacs, Maria; Shukla, Shripaad Y.; Valyi-Nagy, Tibor; Shukla, Deepak

    2009-01-01

    Herpes simplex virus 1 (HSV-1) demonstrates a unique ability to infect a variety of host cell types. Retinal pigment epithelial (RPE) cells form the outermost layer of the retina and provide a potential target for viral invasion and permanent vision impairment. Here we examine the initial cellular and molecular mechanisms that facilitate HSV-1 invasion of human RPE cells. High-resolution confocal microscopy demonstrated initial interaction of green fluorescent protein (GFP)-tagged virions with filopodia-like structures present on cell surfaces. Unidirectional movement of the virions on filopodia to the cell body was detected by live cell imaging of RPE cells, which demonstrated susceptibility to pH-dependent HSV-1 entry and replication. Use of RT-PCR indicated expression of nectin-1, herpes virus entry mediator (HVEM) and 3-O-sulfotransferase-3 (as a surrogate marker for 3-O-sulfated heparan sulfate). HVEM and nectin-1 expression was subsequently verified by flow cytometry. Nectin-1 expression in murine retinal tissue was also demonstrated by immunohistochemistry. Antibodies against nectin-1, but not HVEM, were able to block HSV-1 infection. Similar blocking effects were seen with a small interfering RNA construct specifically directed against nectin-1, which also blocked RPE cell fusion with HSV-1 glycoprotein-expressing Chinese hamster ovary (CHO-K1) cells. Anti-nectin-1 antibodies and F-actin depolymerizers were also successful in blocking the cytoskeletal changes that occur upon HSV-1 entry into cells. Our findings shed new light on the cellular and molecular mechanisms that help the virus to enter the cells of the inner eye. PMID:18803666

  2. Human stem cell-derived retinal epithelial cells activate complement via collectin 11 in response to stress

    DEFF Research Database (Denmark)

    Fanelli, Giorgia; Gonzalez-Cordero, Anai; Gardner, Peter J

    2017-01-01

    induced-pluripotent stem cell (iPSC)-derived RPE cells, particularly with regard to the complement pathway. We focused on collectin-11 (CL-11), a pattern recognition molecule that can trigger complement activation in renal epithelial tissue. We found evidence of constitutive and hypoxia-induced expression......, failed to activate complement. The presence of CL-11 in healthy murine and human retinal tissues confirmed the biological relevance of CL-11. Our data describe a new trigger mechanism of complement activation that could be important in disease pathogenesis and therapeutic interventions....

  3. The novel triterpenoid RTA 408 protects human retinal pigment epithelial cells against H2O2-induced cell injury via NF-E2-related factor 2 (Nrf2 activation

    Directory of Open Access Journals (Sweden)

    Xiaobin Liu

    2016-08-01

    Full Text Available Oxidative stress-induced retinal pigment epithelial (RPE cell damage is an important factor in the pathogenesis of age-related macular degeneration (AMD. Previous studies have shown that RTA 408, a synthetic triterpenoid compound, potently activates Nrf2. This study aimed to investigate the protective effects of RTA 408 in cultured RPE cells during oxidative stress and to determine the effects of RTA 408 on Nrf2 and its downstream target genes. Primary human RPE cells were pretreated with RTA 408 and then incubated in 200 μM H2O2 for 6 h. Cell viability was measured with the WST-8 assay. Apoptosis was quantitatively measured by annexin V/propidium iodide (PI double staining and Hoechst 33342 fluorescent staining. Reduced (GSH and oxidized glutathione (GSSG were measured using colorimetric assays. Nrf2 activation and its downstream effects on phase II enzymes were examined by Western blot. Treatment of RPE cells with nanomolar ranges (10 and 100 nM of RTA 408 markedly attenuated H2O2-induced viability loss and apoptosis. RTA 408 pretreatment significantly protected cells from oxidative stress-induced GSH loss, GSSG formation and decreased ROS production. RTA 408 activated Nrf2 and increased the expression of its downstream genes, such as HO-1, NQO1, SOD2, catalase, Grx1, and Trx1. Consequently, the enzyme activities of NQO1, Grx1, and Trx1 were fully protected by RTA 408 pretreatment under oxidative stress. Moreover, knockdown of Nrf2 by siRNA significantly reduced the cytoprotective effects of RTA 408. In conclusion, our data suggest that RTA 408 protect primary human RPE cells from oxidative stress-induced damage by activating Nrf2 and its downstream genes.

  4. Fisetin and luteolin protect human retinal pigment epithelial cells from oxidative stress-induced cell death and regulate inflammation

    Science.gov (United States)

    Hytti, Maria; Piippo, Niina; Korhonen, Eveliina; Honkakoski, Paavo; Kaarniranta, Kai; Kauppinen, Anu

    2015-01-01

    Degeneration of retinal pigment epithelial (RPE) cells is a clinical hallmark of age-related macular degeneration (AMD), the leading cause of blindness among aged people in the Western world. Both inflammation and oxidative stress are known to play vital roles in the development of this disease. Here, we assess the ability of fisetin and luteolin, to protect ARPE-19 cells from oxidative stress-induced cell death and to decrease intracellular inflammation. We also compare the growth and reactivity of human ARPE-19 cells in serum-free and serum-containing conditions. The absence of serum in the culture medium did not prevent ARPE-19 cells from reaching full confluency but caused an increased sensitivity to oxidative stress-induced cell death. Both fisetin and luteolin protected ARPE-19 cells from oxidative stress-induced cell death. They also significantly decreased the release of pro-inflammatory cytokines into the culture medium. The decrease in inflammation was associated with reduced activation of MAPKs and CREB, but was not linked to NF- κB or SIRT1. The ability of fisetin and luteolin to protect and repair stressed RPE cells even after the oxidative insult make them attractive in the search for treatments for AMD. PMID:26619957

  5. That Escalated Quickly—Planning to Ignore RPE Can Backfire

    Directory of Open Access Journals (Sweden)

    Maik Bieleke

    2017-09-01

    Full Text Available Ratings of perceived exertion (RPE are routinely assessed in exercise science and RPE is substantially associated with physiological criterion measures. According to the psychobiological model of endurance, RPE is a central limiting factor in performance. While RPE is known to be affected by psychological manipulations, it remains to be examined whether RPE can be self-regulated during static muscular endurance exercises to enhance performance. In this experiment, we investigate the effectiveness of the widely used and recommended self-regulation strategy of if-then planning (i.e., implementation intentions in down-regulating RPE and improving performance in a static muscular endurance task. 62 female students (age: M = 23.7 years, SD = 4.0 were randomly assigned to an implementation intention or a control condition and performed a static muscular endurance task. They held two intertwined rings as long as possible while avoiding contacts between the rings. In the implementation intention condition, participants had an if-then plan: “If the task becomes too strenuous for me, then I ignore the strain and tell myself: Keep going!” Every 25 ± 10 s participants reported their RPE along with their perceived pain. Endurance performance was measured as time to failure, along with contact errors as a measure of performance quality. No differences emerged between implementation intention and control participants regarding time to failure and performance quality. However, mixed-effects model analyses revealed a significant Time-to-Failure × Condition interaction for RPE. Compared to the control condition, participants in the implementation intention condition reported substantially greater increases in RPE during the second half of the task and reached higher total values of RPE before task termination. A similar but weaker pattern evinced for perceived pain. Our results demonstrate that RPE during an endurance task can be self-regulated with if

  6. Human mesenchymal stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem; Kassem, Moustapha

    2008-01-01

    Mesenchymal stem cells (MSC) are a group of clonogenic cells present among the bone marrow stroma and capable of multilineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. Due to their ease of isolation and their differentiation potential, MSC are being...... introduced into clinical medicine in variety of applications and through different ways of administration. Here, we discuss approaches for isolation, characterization and directing differentiation of human mesenchymal stem cells (hMSC). An update of the current clinical use of the cells is also provided....

  7. Efficient gene delivery to primary human retinal pigment epithelial cells: The innate and acquired properties of vectors.

    Science.gov (United States)

    Tasharrofi, Nooshin; Kouhkan, Fatemeh; Soleimani, Masoud; Soheili, Zahra-Soheila; Atyabi, Fatemeh; Akbari Javar, Hamid; Abedin Dorkoosh, Farid

    2017-02-25

    The purpose of this study is designing non-viral gene delivery vectors for transfection of the primary human retinal pigment epithelial cells (RPE). In the design process of gene delivery vectors, considering physicochemical properties of vectors alone does not seem to be enough since they interact with constituents of the surrounding environment and hence gain new characteristics. Moreover, due to these interactions, their cargo can be released untimely or undergo degradation before reaching to the target cells. Further, the characteristics of cells itself can also influence the transfection efficacy. For example, the non-dividing property of RPE cells can impede the transfection efficiency which in most studies was ignored by using immortal cell lines. In this study, vectors with different characteristics differing in mixing orders of pDNA, PEI polymer, and PLGA/PEI or PLGA nanoparticles were prepared and characterized. Then, their characteristics and efficacy in gene delivery to RPE cells in the presence of vitreous or fetal bovine serum (FBS) were evaluated. All formulations showed no cytotoxicity and were able to protect pDNA from premature release and degradation in extracellular media. Also, the adsorption of vitreous or serum proteins onto the surface of vectors changed their properties and hence cellular uptake and transfection efficacy. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. In vivo imaging of the retinal pigment epithelial cells

    Science.gov (United States)

    Morgan, Jessica Ijams Wolfing

    The retinal pigment epithelial (RPE) cells form an important layer of the retina because they are responsible for providing metabolic support to the photoreceptors. Techniques to image the RPE layer include autofluorescence imaging with a scanning laser ophthalmoscope (SLO). However, previous studies were unable to resolve single RPE cells in vivo. This thesis describes the technique of combining autofluorescence, SLO, adaptive optics (AO), and dual-wavelength simultaneous imaging and registration to visualize the individual cells in the RPE mosaic in human and primate retina for the first time in vivo. After imaging the RPE mosaic non-invasively, the cell layer's structure and regularity were characterized using quantitative metrics of cell density, spacing, and nearest neighbor distances. The RPE mosaic was compared to the cone mosaic, and RPE imaging methods were confirmed using histology. The ability to image the RPE mosaic led to the discovery of a novel retinal change following light exposure; 568 nm exposures caused an immediate reduction in autofluorescence followed by either full recovery or permanent damage in the RPE layer. A safety study was conducted to determine the range of exposure irradiances that caused permanent damage or transient autofluorescence reductions. Additionally, the threshold exposure causing autofluorescence reduction was determined and reciprocity of radiant exposure was confirmed. Light exposures delivered by the AOSLO were not significantly different than those delivered by a uniform source. As all exposures tested were near or below the permissible light levels of safety standards, this thesis provides evidence that the current light safety standards need to be revised. Finally, with the retinal damage and autofluorescence reduction thresholds identified, the methods of RPE imaging were modified to allow successful imaging of the individual cells in the RPE mosaic while still ensuring retinal safety. This thesis has provided a

  9. Memory, reconsolidation and extinction in Lymnaea require the soma of RPeD1.

    Science.gov (United States)

    Sangha, Susan; Varshney, Nishi; Fras, Mary; Smyth, Kim; Rosenegger, David; Parvez, Kashif; Sadamoto, Hisayo; Lukowiak, Ken

    2004-01-01

    The central pattern generator (CPG) that drives aerial respiratory behaviour in Lymnaea consists of 3 neurons. One of these, RPeD1--the cell that initiates activity in the circuit, plays an absolutely necessary role as a site for memory formation, memory reconsolidation, and extinction. Using an operant conditioning training procedure that results in a long-term non-declarative memory (LTM), we decrease the occurrence of aerial respiratory behaviour. Since snails can still breathe cutaneously learning this procedure is not harmful. Concomitant with behavioural memory are changes in the spiking activity of RPeD1. Going beyond neural correlates of memory we directly show that RPeD1 is a necessary site for LTM formation. Expanding on this finding we show that this neuron is also a necessary site for memory reconsolidation and 'Pavlovian' extinction. As far as we can determine, this is the first time a single neuron has been shown to be a necessary site for these different aspects memory. RPeD1 is thus a key neuron mediating different hierarchical aspects of memory. We are now in a position to determine the necessary neuronal, molecular and proteomic events in this neuron that are causal to memory formation, reconsolidation and extinction.

  10. In vitro differentiation of adipose-tissue-derived mesenchymal stem cells into neural retinal cells through expression of human PAX6 (5a) gene.

    Science.gov (United States)

    Rezanejad, Habib; Soheili, Zahra-Soheila; Haddad, Farhang; Matin, Maryam M; Samiei, Shahram; Manafi, Ali; Ahmadieh, Hamid

    2014-04-01

    The neural retina is subjected to various degenerative conditions. Regenerative stem-cell-based therapy holds great promise for treating severe retinal degeneration diseases, although many drawbacks remain to be overcome. One important problem is to gain authentically differentiated cells for replacement. Paired box 6 protein (5a) (PAX6 (5a)) is a highly conserved master control gene that has an essential role in the development of the vertebrate visual system. Human adipose-tissue-derived stem cell (hADSC) isolation was performed by using fat tissues and was confirmed by the differentiation potential of the cells into adipocytes and osteocytes and by their surface marker profile. The coding region of the human PAX6 (5a) gene isoform was cloned and lentiviral particles were propagated in HEK293T. The differentiation of hADSCs into retinal cells was characterized by morphological characteristics, quantitative real-time reverse transcription plus the polymerase chain reaction (qPCR) and immunocytochemistry (ICC) for some retinal cell-specific and retinal pigmented epithelial (RPE) cell-specific markers. hADSCs were successfully isolated. Flow cytometric analysis of surface markers indicated the high purity (~97 %) of isolated hADSCs. After 30 h of post-transduction, cells gradually showed the characteristic morphology of neuronal cells and small axon-like processes emerged. qPCR and ICC confirmed the differentiation of some neural retinal cells and RPE cells. Thus, PAX6 (5a) transcription factor expression, together with medium supplemented with fibronectin, is able to induce the differentiation of hADSCs into retinal progenitors, RPE cells and photoreceptors.

  11. Voltage-dependent ion channels in the mouse RPE: comparison with Norrie disease mice.

    Science.gov (United States)

    Wollmann, Guido; Lenzner, Steffen; Berger, Wolfgang; Rosenthal, Rita; Karl, Mike O; Strauss, Olaf

    2006-03-01

    We studied electrophysiological properties of cultured retinal pigment epithelial (RPE) cells from mouse and a mouse model for Norrie disease. Wild-type RPE cells revealed the expression of ion channels known from other species: delayed-rectifier K(+) channels composed of Kv1.3 subunits, inward rectifier K(+) channels, Ca(V)1.3 L-type Ca(2+) channels and outwardly rectifying Cl(-) channels. Expression pattern and the ion channel characteristics current density, blocker sensitivity, kinetics and voltage-dependence were compared in cells from wild-type and Norrie mice. Although no significant differences were observed, our study provides a base for future studies on ion channel function and dysfunction in transgenic mouse models.

  12. Human innate lymphoid cells.

    Science.gov (United States)

    Mjösberg, Jenny; Spits, Hergen

    2016-11-01

    Innate lymphoid cells (ILCs) are increasingly acknowledged as important mediators of immune homeostasis and pathology. ILCs act as early orchestrators of immunity, responding to epithelium-derived signals by expressing an array of cytokines and cell-surface receptors, which shape subsequent immune responses. As such, ILCs make up interesting therapeutic targets for several diseases. In patients with allergy and asthma, group 2 innate lymphoid cells produce high amounts of IL-5 and IL-13, thereby contributing to type 2-mediated inflammation. Group 3 innate lymphoid cells are implicated in intestinal homeostasis and psoriasis pathology through abundant IL-22 production, whereas group 1 innate lymphoid cells are accumulated in chronic inflammation of the gut (inflammatory bowel disease) and lung (chronic obstructive pulmonary disease), where they contribute to IFN-γ-mediated inflammation. Although the ontogeny of mouse ILCs is slowly unraveling, the development of human ILCs is far from understood. In addition, the growing complexity of the human ILC family in terms of previously unrecognized functional heterogeneity and plasticity has generated confusion within the field. Here we provide an updated view on the function and plasticity of human ILCs in tissue homeostasis and disease. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  13. Long Non-Coding RNA MALAT1 Mediates Transforming Growth Factor Beta1-Induced Epithelial-Mesenchymal Transition of Retinal Pigment Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Shuai Yang

    Full Text Available To study the role of long non-coding RNA (lncRNA MALAT1 in transforming growth factor beta 1 (TGF-β1-induced epithelial-mesenchymal transition (EMT of retinal pigment epithelial (RPE cells.ARPE-19 cells were cultured and exposed to TGF-β1. The EMT of APRE-19 cells is confirmed by morphological change, as well as the increased expression of alpha-smooth muscle actin (αSMA and fibronectin, and the down-regulation of E-cadherin and Zona occludin-1(ZO-1 at both mRNA and protein levels. The expression of lncRNA MALAT1 in RPE cells were detected by quantitative real-time PCR. Knockdown of MALAT1 was achieved by transfecting a small interfering RNA (SiRNA. The effect of inhibition of MALAT1 on EMT, migration, proliferation, and TGFβ signalings were observed. MALAT1 expression was also detected in primary RPE cells incubated with proliferative vitreoretinopathy (PVR vitreous samples.The expression of MALAT1 is significantly increased in RPE cells incubated with TGFβ1. MALAT1 silencing attenuates TGFβ1-induced EMT, migration, and proliferation of RPE cells, at least partially through activating Smad2/3 signaling. MALAT1 is also significantly increased in primary RPE cells incubated with PVR vitreous samples.LncRNA MALAT1 is involved in TGFβ1-induced EMT of human RPE cells and provides new understandings for the pathogenesis of PVR.

  14. USING SESSION RPE TO MONITOR DIFFERENT METHODS OF RESISTANCE EXERCISE

    Directory of Open Access Journals (Sweden)

    Alison D. Egan

    2006-06-01

    Full Text Available The purpose of this study was to compare session rating of perceived exertion for different resistance training techniques in the squat exercise. These techniques included traditional resistance training, super slow, and maximal power training. Fourteen college-age women (Mean ± SD; age = 22 ± 3 years; height = 1.68 ± 0. 07 m completed three experimental trials in a randomized crossover design. The traditional resistance training protocol consisted of 6 sets of 6 repetitions of squats using 80% of 1-RM. The super slow protocol consisted of 6 sets of 6 repetitions using 55% of 1-RM. The maximal power protocol consisted of 6 sets of 6 repetitions using 30% of 1-RM. Rating of perceived exertion (RPE measures were obtained following each set using Borg's CR-10 scale. In addition, a session RPE value was obtained 30 minutes following each exercise session. When comparing average RPE and session RPE, no significant difference was found. However, power training had significantly lower (p < 0.05 average and session RPE (4.50 ± 1.9 and 4.5 ± 2.1 compared to both super slow training (7.81 ± 1.75 and 7.43 ± 1.73 and traditional training (7.33 ± 1.52 and 7.13 ± 1.73. The results indicate that session RPE values are not significantly different from the more traditional methods of measuring RPE during exercise bouts. It does appear that the resistance training mode that is used results in differences in perceived exertion that does not relate directly to the loading that is used. Using session RPE provides practitioners with the same information about perceived exertion as the traditional RPE measures. Taking a single measure following a training session would appear to be much easier than using multiple measures of RPE throughout a resistance training workout. However, practitioners should also be aware that the RPE does not directly relate to the relative intensity used and appears to be dependent on the mode of resistance exercise that is used

  15. Human leukaemic cells

    International Nuclear Information System (INIS)

    Andronikashvili, E.L.; Mosulishvili, L.M.; Belokobil'skiy, A.I.; Kharabadze, N.E.; Shonia, N.I.; Desai, L.S.; Foley, G.E.

    1976-01-01

    The results of the determination of trace elements in nucleic acids and histones in human leukaemic cells by activation analysis are reported. The Cr 2+ , Fe 2+ , Zn 2+ , Co 2+ and Sb 2+ content of DNA and RNA of leukaemic cells compared to that of lymphocytes from a patient with infectious mononucleosis or a normal donor are shown tabulated. Similar comparisons are shown for the same trace metal content of histones isolated from the same type of cells. It is felt that the results afford further interesting speculation that trace metals may be involved in the interactions between histones and DNA (especially at the binding sites of histones to DNA), which affect transcription characteristics. (U.K.)

  16. Controlled surface morphology and hydrophilicity of polycaprolactone toward human retinal pigment epithelium cells.

    Science.gov (United States)

    Shahmoradi, Saleheh; Yazdian, Fatemeh; Tabandeh, Fatemeh; Soheili, Zahra-Soheila; Hatamian Zarami, Ashraf Sadat; Navaei-Nigjeh, Mona

    2017-04-01

    Applying scaffolds as a bed to enhance cell proliferation and even differentiation is one of the treatment of retina diseases such as age-related macular degeneration (AMD) which deteriorating photoreceptors and finally happening blindness. In this study, aligned polycaprolactone (PCL) nanofibers were electrospun and at different conditions and their characteristics were measured by scanning electron microscope (SEM) and contact angle. Response surface methodology (RSM) was used to optimize the diameter of fabricated nanofibers. Two factors as solution concentration and voltage value were considered as independent variables and their effects on nanofibers' diameters were evaluated by central composite design and the optimum conditions were obtained as 0.12g/mL and 20kV, respectively. In order to decrease the hydrophobicity of PCL, the surface of the fabricated scaffolds was modified by alkaline hydrolysis method. Contact time of the scaffolds and alkaline solution and concentration of alkaline solution were optimized using Box Behnken design and (120min and 5M were the optimal, respectively). Contact angle measurement showed the high hydrophilicity of treated scaffolds (with contact angle 7.48°). Plasma surface treatment was applied to compare the effect of using two kinds of surface modification methods simultaneously on hydrolyzed scaffolds. The RPE cells grown on scaffolds were examined by immunocytochemistry (ICC), MTT and continuous inspection of cellular morphology. Interestingly, Human RPE cells revealed their characteristic morphology on hydrolyzed scaffold well. As a result, we introduced a culture substrate with low diameter (185.8nm), high porosity (82%) and suitable hydrophilicity (with contact angle 7.48 degree) which can be promising for hRPE cell transplantation. Copyright © 2016. Published by Elsevier B.V.

  17. Survival Improvement in Human Retinal Pigment Epithelial Cells via Fas Receptor Targeting by miR-374a.

    Science.gov (United States)

    Tasharrofi, Nooshin; Kouhkan, Fatemeh; Soleimani, Masoud; Soheili, Zahra-Sheila; Kabiri, Mahboubeh; Mahmoudi Saber, Mohaddeseh; Dorkoosh, Farid Abedin

    2017-12-01

    Oxidative conditions of the eye could contribute to retinal cells loss through activating the Fas-L/Fas pathway. This phenomenon is one of the leading causes of some ocular diseases like age-related macular degeneration (AMD). By targeting proteins at their mRNA level, microRNAs (miRNAs) can regulate gene expression and cell function. The aim of the present study is to investigate Fas targeting by miR-374a and find whether it can inhibit Fas-mediated apoptosis in primary human retinal pigment epithelial (RPE) cells under oxidative stress. So, the primary human RPE cells were transfected with pre-miR-374a pLEX construct using polymeric carrier and were exposed to H 2 O 2 (200 μM) as an oxidant agent for induction of Fas expression. Fas expression at mRNA and protein level was evaluated by quantitative real-time PCR and Western blot analysis, respectively. These results revealed that miR-374a could prevent Fas upregulation under oxidative conditions. Moreover, Luciferase activity assay confirmed that Fas could be a direct target of miR-374a. The cell viability studies demonstrated that caspase-3 activity was negligible in miR-374a treated cells compared to the controls. Our data suggest miR-374a is a negative regulator of Fas death receptor which is able to enhance the cell survival and protect RPE cells against oxidative conditions. J. Cell. Biochem. 118: 4854-4861, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  18. SPECIFIC ROLE OF LYMPHATIC MARKER PODOPLANIN IN RETINAL PIGMENT EPITHELIAL CELLS

    Science.gov (United States)

    Grimaldo, S.; Garcia, M.; Zhang, H.; Chen, L.

    2015-01-01

    Podoplanin is a small transmembrane glycoprotein widely known to be a marker for lymphatic endothelial cells. In this study, we identify a novel localization of podoplanin in the retinal pigment epithelium (RPE), a cellular monolayer critically involved in the visual process. Using a small interfering RNA (siRNA)-mediated gene silencing approach, we have also demonstrated, for the first time, that podoplanin depletion in human RPE cells leads to a marked reduction of cell aggregates and tight junctions. Additionally, the podoplanin-depleted cells also exhibit a significantly lower rate of proliferation. These data together indicate that podoplanin plays a crucial role in RPE cell functions. Further investigation on this factor may reveal novel mechanisms and therapeutic strategies for RPE-related eye diseases, such as proliferative retinopathy and age-related macular degeneration. PMID:21226415

  19. Anti-apoptotic effects of Curcuma longa L. extract and its curcuminoids against blue light-induced cytotoxicity in A2E-laden human retinal pigment epithelial cells.

    Science.gov (United States)

    Park, Sang-Il; Lee, Eun Hye; Kim, So Ra; Jang, Young Pyo

    2017-03-01

    The purpose of the study was to investigate the protective effect of the Curcuma longa L. extract (CLE) and its curcuminoids against blue light-induced cytotoxicity in human retinal pigment epithelial (RPE) cells laded with A2E. A2E has been concerned in age-related macular degeneration (AMD). To perform this study, A2E-accumulated ARPE-19 cells were exposed to blue light to induce cytotoxicity. The cytotoxicity and apoptotic gene expression levels were evaluated using a lactate dehydrogenase (LDH) assay and real-time PCR analysis, respectively. Curcuma longa L. extract was found to exert a protective effect in a dose-dependent manner. At a concentration of 15 μm, curcumin, demethoxycurcumin and bisdemethoxycurcumin exerted significant protective effects against blue light-induced cytotoxicity. Treatment with CLE and curcuminoids meaningfully reduced the mRNA levels of c-Abl and p53, which was known to be augmented in apoptotic RPE cells. Demethoxycurcumin and bisdemethoxycurcumin were found to inhibit p38 expression, which is increased in blue light-irradiated A2E-accumulated RPE cells. Curcuma longa L. extract and its curcuminoids provided significant protection against photooxidative damage and apoptosis in the RPE cells. Our results suggest that curcuminoids may show potential in the treatment of AMD. © 2017 Royal Pharmaceutical Society.

  20. Functional recovery after experimental RPE debridement, mfERG studies in a porcine model

    DEFF Research Database (Denmark)

    Sørensen, Nina Buus; Lassota, Nathan; Kyhn, Maria Voss

    2013-01-01

    BACKGROUND: The correlation between histologically identified regeneration of retinal pigment epithelium (RPE) and functional outcome measured by multifocal electroretinography (mfERG) following surgical debridement is examined in a porcine model. In humans, visual acuity is reduced in diseases......, and by brushing the Bruch's membrane with a silicone catheter. Immediately following surgery (baseline) and after 2 and 6 weeks respectively, the animals were examined by mfERG, fundus photographs (FPs), fluorescein angiograms (FAs), and histopathology. RESULTS: The mfERG P1 amplitude was decreased 2 weeks (T2....... CONCLUSION: This is the first study to show that the histological regeneration of hypopigmented RPE correlates to a return of the retinal function, measured by mfERG....

  1. Multi-level communication of human retinal pigment epithelial cells via tunneling nanotubes.

    Directory of Open Access Journals (Sweden)

    Dierk Wittig

    Full Text Available BACKGROUND: Tunneling nanotubes (TNTs may offer a very specific and effective way of intercellular communication. Here we investigated TNTs in the human retinal pigment epithelial (RPE cell line ARPE-19. Morphology of TNTs was examined by immunostaining and scanning electron microscopy. To determine the function of TNTs between cells, we studied the TNT-dependent intercellular communication at different levels including electrical and calcium signalling, small molecular diffusion as well as mitochondrial re-localization. Further, intercellular organelles transfer was assayed by FACS analysis. METHODOLOGY AND PRINCIPAL FINDINGS: Microscopy showed that cultured ARPE-19 cells are frequently connected by TNTs, which are not attached to the substratum. The TNTs were straight connections between cells, had a typical diameter of 50 to 300 nm and a length of up to 120 µm. We observed de novo formation of TNTs by diverging from migrating cells after a short time of interaction. Scanning electron microscopy confirmed characteristic features of TNTs. Fluorescence microscopy revealed that TNTs between ARPE-19 cells contain F-actin but no microtubules. Depolymerisation of F-actin, induced by addition of latrunculin-B, led to disappearance of TNTs. Importantly, these TNTs could function as channels for the diffusion of small molecules such as Lucifer Yellow, but not for large molecules like Dextran Red. Further, organelle exchange between cells via TNTs was observed by microscopy. Using Ca²⁺ imaging we show the intercellular transmission of calcium signals through TNTs. Mechanical stimulation led to membrane depolarisation, which expand through TNT connections between ARPE-19 cells. We further demonstrate that TNTs can mediate electrical coupling between distant cells. Immunolabelling for Cx43 showed that this gap junction protein is interposed at one end of 44% of TNTs between ARPE-19 cells. CONCLUSIONS AND SIGNIFICANCE: Our observations indicate that

  2. Quantitative Fundus Autofluorescence in Best Vitelliform Macular Dystrophy: RPE Lipofuscin is not Increased in Non-Lesion Areas of Retina.

    Science.gov (United States)

    Sparrow, Janet R; Duncker, Tobias; Woods, Russell; Delori, François C

    2016-01-01

    Since the lipofuscin of retinal pigment epithelial (RPE) cells has been implicated in the pathogenesis of Best vitelliform macular dystrophy, we quantified fundus autofluorescence (quantitative fundus autofluorescence, qAF) as an indirect measure of RPE lipofuscin levels. Mean non-lesion qAF was found to be within normal limits for age. By spectral domain optical coherence tomography (SD-OCT) vitelliform lesions presented as fluid-filled subretinal detachments containing reflective material. We discuss photoreceptor outer segment debris as the source of the intense fluorescence of these lesions and loss of anion channel functioning as an explanation for the bullous photoreceptor-RPE detachment. Unexplained is the propensity of the disease for central retina.

  3. Human leukaemic cells

    International Nuclear Information System (INIS)

    Andronikashvili, E.L.; Mosulishvili, L.M.; Belokobil'skiy, A.I.; Kharabadze, N.E.; Shonia, N.I.; Desai, L.S.; Foley, G.E.

    1976-01-01

    Trace metals were measured by neutron-activation analyses in purified nucleic acids and histone(s) of lymphocytes from patients with acute lymphocytic leukaemia or infectious mononucleosis, and from normal donors. DNA isolated from lymphocytes of a patient with infectious mononucleosis and a normal donor showed a high content of Cr 2+ , Sb 2+ , Fe 2+ , Zn 2+ , whereas DNA of lymphoblasts from a patient with acute lymphocytic leukaemia had a lower content of these trace metals, but the Co 2+ content was 20-fold higher than in DNA of normal donor lymphocytic cells. Total histones from leukaemic cells had higher contents of most of the trace metals except for Zn 2+ , which was present in lesser concentration than in histones from normal donor lymphocytic cells. Lysine-rich (F1) histones showed lower contents of Cr 2+ , Sb 2+ and Co 2+ , whereas arginine-rich (F3) histones had significantly higher contents of these trace metals. These observations may be of interest in that F3 histones more effectively inhibit RNA synthesis in human lymphocytic cells than do other species of histones. (author)

  4. TGF-β-stimulated aberrant expression of class III β-tubulin via the ERK signaling pathway in cultured retinal pigment epithelial cells

    International Nuclear Information System (INIS)

    Chung, Eun Jee; Chun, Ji Na; Jung, Sun-Ah; Cho, Jin Won; Lee, Joon H.

    2011-01-01

    Highlights: ► TGF-β induces aberrant expression of βIII in RPE cells via the ERK pathway. ► TGF-β increases O-GlcNAc modification of βIII in RPE cells. ► Mature RPE cells have the capacity to express a neuron-associated gene by TGF-β. -- Abstract: The class III β-tubulin isotype (β III ) is expressed exclusively by neurons within the normal human retina and is not present in normal retinal pigment epithelial (RPE) cells in situ or in the early phase of primary cultures. However, aberrant expression of class III β-tubulin has been observed in passaged RPE cells and RPE cells with dedifferentiated morphology in pathologic epiretinal membranes from idiopathic macular pucker, proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR). Transforming growth factor-β (TGF-β) has been implicated in dedifferentiation of RPE cells and has a critical role in the development of proliferative vitreoretinal diseases. Here, we investigated the potential effects of TGF-β on the aberrant expression of class III β-tubulin and the intracellular signaling pathway mediating these changes. TGF-β-induced aberrant expression and O-linked-β-N-acetylglucosamine (O-GlcNac) modification of class III β-tubulin in cultured RPE cells as determined using Western blotting, RT-PCR and immunocytochemistry. TGF-β also stimulated phosphorylation of ERK. TGF-β-induced aberrant expression of class III β-tubulin was significantly reduced by pretreatment with U0126, an inhibitor of ERK phosphorylation. Our findings indicate that TGF-β stimulated aberrant expression of class III β-tubulin via activation of the ERK signaling pathway. These data demonstrate that mature RPE cells have the capacity to express a neuron-associated gene in response to TGF-β stimulation and provide useful information towards understanding the pathogenesis of proliferative vitreoretinal diseases.

  5. TGF-{beta}-stimulated aberrant expression of class III {beta}-tubulin via the ERK signaling pathway in cultured retinal pigment epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eun Jee [Department of Ophthalmology, National Health Insurance Corporation Ilsan Hospital, Gyeonggi-do (Korea, Republic of); Chun, Ji Na; Jung, Sun-Ah [Konyang University Myunggok Medical Research Institute, Kim' s Eye Hospital, Konyang University College of Medicine, Seoul (Korea, Republic of); Cho, Jin Won [Department of Biology, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Lee, Joon H., E-mail: joonhlee@konyang.ac.kr [Konyang University Myunggok Medical Research Institute, Kim' s Eye Hospital, Konyang University College of Medicine, Seoul (Korea, Republic of)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer TGF-{beta} induces aberrant expression of {beta}III in RPE cells via the ERK pathway. Black-Right-Pointing-Pointer TGF-{beta} increases O-GlcNAc modification of {beta}III in RPE cells. Black-Right-Pointing-Pointer Mature RPE cells have the capacity to express a neuron-associated gene by TGF-{beta}. -- Abstract: The class III {beta}-tubulin isotype ({beta}{sub III}) is expressed exclusively by neurons within the normal human retina and is not present in normal retinal pigment epithelial (RPE) cells in situ or in the early phase of primary cultures. However, aberrant expression of class III {beta}-tubulin has been observed in passaged RPE cells and RPE cells with dedifferentiated morphology in pathologic epiretinal membranes from idiopathic macular pucker, proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR). Transforming growth factor-{beta} (TGF-{beta}) has been implicated in dedifferentiation of RPE cells and has a critical role in the development of proliferative vitreoretinal diseases. Here, we investigated the potential effects of TGF-{beta} on the aberrant expression of class III {beta}-tubulin and the intracellular signaling pathway mediating these changes. TGF-{beta}-induced aberrant expression and O-linked-{beta}-N-acetylglucosamine (O-GlcNac) modification of class III {beta}-tubulin in cultured RPE cells as determined using Western blotting, RT-PCR and immunocytochemistry. TGF-{beta} also stimulated phosphorylation of ERK. TGF-{beta}-induced aberrant expression of class III {beta}-tubulin was significantly reduced by pretreatment with U0126, an inhibitor of ERK phosphorylation. Our findings indicate that TGF-{beta} stimulated aberrant expression of class III {beta}-tubulin via activation of the ERK signaling pathway. These data demonstrate that mature RPE cells have the capacity to express a neuron-associated gene in response to TGF-{beta} stimulation and provide useful information

  6. Loss of Extracellular Signal-Regulated Kinase 1/2 in the Retinal Pigment Epithelium Leads to RPE65 Decrease and Retinal Degeneration.

    Science.gov (United States)

    Pyakurel, Aswin; Balmer, Delphine; Saba-El-Leil, Marc K; Kizilyaprak, Caroline; Daraspe, Jean; Humbel, Bruno M; Voisin, Laure; Le, Yun Z; von Lintig, Johannes; Meloche, Sylvain; Roduit, Raphaël

    2017-12-15

    Recent work suggested that the activity of extracellular signal-regulated kinase 1/2 (ERK1/2) is increased in the retinal pigment epithelium (RPE) of age-related macular degeneration (ARMD) patients and therefore could be an attractive therapeutic target. Notably, ERK1/2 pathway inhibitors are used in cancer therapy, with severe and noncharacterized ocular side effects. To decipher the role of ERK1/2 in RPE cells, we conditionally disrupted the Erk1 and Erk2 genes in mouse RPE. The loss of ERK1/2 activity resulted in a significant decrease in the level of RPE65 expression, a decrease in ocular retinoid levels concomitant with low visual function, and a rapid disorganization of RPE cells, ultimately leading to retinal degeneration. Our results identify the ERK1/2 pathway as a direct regulator of the visual cycle and a critical component of the viability of RPE and photoreceptor cells. Moreover, our results caution about the need for a very fine adjustment of kinase inhibition in cancer or ARMD treatment in order to avoid ocular side effects. Copyright © 2017 Pyakurel et al.

  7. Isolation, Characterization, and Establishment of Spontaneously Immortalized Cell Line HRPE-2S With Stem Cell Properties.

    Science.gov (United States)

    Shams Najafabadi, Hoda; Soheili, Zahra-Soheila; Samiei, Shahram; Ahmadieh, Hamid; Ranaei Pirmardan, Ehsan; Masoumi, Maryam

    2017-10-01

    The retinal pigment epithelium is a monolayer of highly specialized pigmented cells located between the neural retina and the Bruch's membrane of the choroid. RPE cells play a crucial role in the maintenance and function of the underlying photoreceptors. This study introduces a spontaneously arising human retinal pigment epithelial cell line, HRPE-2S, which was isolated from primary RPE cell culture of 2 days old male donor. We characterized morphology and functional properties of the new cell line. The immortalized cell line was maintained in culture for more than 70 passages and 240 divisions. The average doubling time of the cells was approximately 22 h and got freezed at 26th passage. The cell line expressed RPE-specific markers RPE65 and cell junction protein ZO1 as an epithelial cell marker. It also expressed CHX10, PAX6, Nestin, SOX2 as stem and retinal progenitor cell markers. Ki67 as a marker of cell proliferation was expressed in all HRPE-2S cells. It represented typical epithelial cobblestone morphology and did not phenotypically change through several passages. Stem cell-like aggregations (neurospheres) were observed in SEM microscopy. The cells represented high mitotic index. They could be viable under hypoxic conditions and serum deprivation. According to functional studies, the cell line exhibited stem cell-like behaviors with particular emphasis on its self-renewal capacity. LDH isoenzymes expression pattern confirmed the same cellular source for both of the HRPE-2S cells and primary RPE cells. Characteristics of HRPE-2S cells promise it as an in vitro model for RPE stem cell-based researches. J. Cell. Physiol. 232: 2626-2640, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Highly sensitive in vitro methods for detection of residual undifferentiated cells in retinal pigment epithelial cells derived from human iPS cells.

    Directory of Open Access Journals (Sweden)

    Takuya Kuroda

    Full Text Available Human induced pluripotent stem cells (hiPSCs possess the capabilities of self-renewal and differentiation into multiple cell types, and they are free of the ethical problems associated with human embryonic stem cells (hESCs. These characteristics make hiPSCs a promising choice for future regenerative medicine research. There are significant obstacles, however, preventing the clinical use of hiPSCs. One of the most obvious safety issues is the presence of residual undifferentiated cells that have tumorigenic potential. To locate residual undifferentiated cells, in vivo teratoma formation assays have been performed with immunodeficient animals, which is both costly and time-consuming. Here, we examined three in vitro assay methods to detect undifferentiated cells (designated an in vitro tumorigenicity assay: soft agar colony formation assay, flow cytometry assay and quantitative real-time polymerase chain reaction assay (qRT-PCR. Although the soft agar colony formation assay was unable to detect hiPSCs even in the presence of a ROCK inhibitor that permits survival of dissociated hiPSCs/hESCs, the flow cytometry assay using anti-TRA-1-60 antibody detected 0.1% undifferentiated hiPSCs that were spiked in primary retinal pigment epithelial (RPE cells. Moreover, qRT-PCR with a specific probe and primers was found to detect a trace amount of Lin28 mRNA, which is equivalent to that present in a mixture of a single hiPSC and 5.0×10⁴ RPE cells. Our findings provide highly sensitive and quantitative in vitro assays essential for facilitating safety profiling of hiPSC-derived products for future regenerative medicine research.

  9. Acute and session RPE responses during resistance training: Bouts ...

    African Journals Online (AJOL)

    Journal Home > Vol 21, No 1 (2009) > ... On separate days in a counterbalanced order, subjects performed 3 sets of each exercise to volitional failure at a ... total work and acute RPE were significantly greater (p=0.01) for LI for all exercises.

  10. Genome engineering in human cells.

    Science.gov (United States)

    Song, Minjung; Kim, Young-Hoon; Kim, Jin-Soo; Kim, Hyongbum

    2014-01-01

    Genome editing in human cells is of great value in research, medicine, and biotechnology. Programmable nucleases including zinc-finger nucleases, transcription activator-like effector nucleases, and RNA-guided engineered nucleases recognize a specific target sequence and make a double-strand break at that site, which can result in gene disruption, gene insertion, gene correction, or chromosomal rearrangements. The target sequence complexities of these programmable nucleases are higher than 3.2 mega base pairs, the size of the haploid human genome. Here, we briefly introduce the structure of the human genome and the characteristics of each programmable nuclease, and review their applications in human cells including pluripotent stem cells. In addition, we discuss various delivery methods for nucleases, programmable nickases, and enrichment of gene-edited human cells, all of which facilitate efficient and precise genome editing in human cells.

  11. Human Umbilical Cord Mesenchymal Stem Cells: Subpopulations and Their Difference in Cell Biology and Effects on Retinal Degeneration in RCS Rats.

    Science.gov (United States)

    Wang, L; Li, P; Tian, Y; Li, Z; Lian, C; Ou, Q; Jin, C; Gao, F; Xu, J-Y; Wang, J; Wang, F; Zhang, J; Zhang, J; Li, W; Tian, H; Lu, L; Xu, G-T

    2017-01-01

    Human umbilical cord mesenchymal stem cells (hUC-MSCs) are potential candidates for treating retinal degeneration (RD). To further study the biology and therapeutic effects of the hUC-MSCs on retinal degeneration. Two hUC-MSC subpopulations, termed hUC-MSC1 and hUC-MSC2, were isolated by single-cell cloning method and their therapeutic functions were compared in RCS rat, a RD model. Although both subsets satisfied the basic requirements for hUC-MSCs, they were significantly different in morphology, proliferation rate, differentiation capacity, phenotype and gene expression. Furthermore, only the smaller, fibroblast-like, faster growing subset hUC-MSC1 displayed stronger colony forming potential as well as adipogenic and osteogenic differentiation capacities. When the two subsets were respectively transplanted into the subretinal spaces of RCS rats, both subsets survived, but only hUC-MSC1 expressed RPE cell markers Bestrophin and RPE65. More importantly, hUC-MSC1 showed stronger rescue effect on the retinal function as indicated by the higher b-wave amplitude on ERG examination, thicker retinal nuclear layer, and decreased apoptotic photoreceptors. When both subsets were treated with interleukin-6, mimicking the inflammatory environment when the cells were transplanted into the eyes with degenerated retina, hUC-MSC1 expressed much higher levels of trophic factors in comparison with hUC-MSC2. The data here, in addition to prove the heterogeneity of hUC-MSCs, confirmed that the stronger therapeutic effects of hUC-MSC1 were attributed to its stronger anti-apoptotic effect, paracrine of trophic factors and potential RPE cell differentiation capacity. Thus, the subset hUC-MSC1, not the other subset or the ungrouped hUC-MSCs should be used for effective treatment of RD. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. New medium used in the differentiation of human pluripotent stem cells to retinal cells is comparable to fetal human eye tissue.

    Science.gov (United States)

    Wang, Xiaobing; Xiong, Kai; Lin, Cong; Lv, Lei; Chen, Jing; Xu, Chongchong; Wang, Songtao; Gu, Dandan; Zheng, Hua; Yu, Hurong; Li, Yan; Xiao, Honglei; Zhou, Guomin

    2015-06-01

    Human pluripotent stem cells (hPSCs) have the potential to differentiate along the retinal lineage. However, most induction systems are dependent on multiple small molecular compounds such as Dkk-1, Lefty-A, and retinoic acid. In the present study, we efficiently differentiated hPSCs into retinal cells using a retinal differentiation medium (RDM) without the use of small molecular compounds. This novel differentiation system recapitulates retinal morphogenesis in humans, i.e. hPSCs gradually differentiate into optic vesicle-shaped spheres, followed by optic cup-shaped spheres and, lastly, retinal progenitor cells. Furthermore, at different stages, hPSC-derived retinal cells mirror the transcription factor expression profiles seen in their counterparts during human embryogenesis. Most importantly, hinge epithelium was found between the hPSC-derived neural retina (NR) and retinal pigment epithelium (RPE). These data suggest that our culture system provides a new method for generating hPSC-derived retinal cells that, for the first time, might be used in human transplantation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Photobleaching and Fluorescence Recovery of RPE Bisretinoids.

    Directory of Open Access Journals (Sweden)

    Zhao Liu

    Full Text Available The autofluorescence of the retina that originates primarily from lipofuscin fluorophores in retinal pigment epithelial cells, is observed to undergo photobleaching during the acquisition of fundus autofluorescence images. Bisretinoid fluorophores isolated from retinal pigment epithelial cells have the spectral characteristics consistent with their being the source of fundus autofluorescence. Clinically relevant experiments were designed to better understand conditions in the micromilieu of bisretinoid fluorophores that can influence fluorescence efficiencies, photobleaching, and subsequent fluorescence recovery of this fluorophore. The consumption of the bisretinoid A2E due to photooxidation-induced degradation was quantified in solvent systems of variable relative permittivity (formerly called dielectric constant, in micelles, and in phospholipid vesicles of varying composition. Reorganization within biphasic systems was also examined. A2E content was measured by high performance liquid chromatography (HPLC and fluorescence intensity was quantified spectroscopically. As solvent polarity was increased, A2E fluorescent spectra exhibited red-shifted maxima and reduced intensity. A2E was depleted by light irradiation and the loss was more pronounced in less polar solvents, lower concentrations of anionic surfactant, and in gel- versus fluid-ordered phospholipid liposomes. Conditions that permit A2E aggregation promoted photooxidation/photodegradation, while movement of A2E between bisphasic systems was associated with fluorescence recovery after photobleaching. The fluorescence characteristics of A2E are subject to environmental modulation. Photooxidation and photodegradation of bisretinoid can account for fundus autofluorescence photobleaching. Return of fluorescence intensity after photobleaching likely occurs due to redistribution of A2E fractions amongst co-existing heterogeneous microdomains of the lysosomal compartment.

  14. Human stromal (mesenchymal) stem cells

    DEFF Research Database (Denmark)

    Aldahmash, Abdullah; Zaher, Walid; Al-Nbaheen, May

    2012-01-01

    Human stromal (mesenchymal) stem cells (hMSC) represent a group of non-hematopoietic stem cells present in the bone marrow stroma and the stroma of other organs including subcutaneous adipose tissue, placenta, and muscles. They exhibit the characteristics of somatic stem cells of self......-renewal and multi-lineage differentiation into mesoderm-type of cells, e.g., to osteoblasts, adipocytes, chondrocytes and possibly other cell types including hepatocytes and astrocytes. Due to their ease of culture and multipotentiality, hMSC are increasingly employed as a source for cells suitable for a number...

  15. 7,8-Dihydroxyflavone ameliorates high-glucose induced diabetic apoptosis in human retinal pigment epithelial cells by activating TrkB.

    Science.gov (United States)

    Yu, Xiaoyi; Liu, Qiuhong; Wang, Xiaochuan; Liu, Hong; Wang, Yan

    2018-01-01

    In diabetic retinopathy, prolonged high-level blood glucose induced significant impairments among various retinal tissues, including retinal pigment epithelial (RPE) cells. In an in vitro model of human RPE cells, we evaluated whether 7,8-Dihydroxyflavone (DHF) may effectively prevent high glucose-induced diabetic apoptosis among human RPE cells. ARPE-19 cells, a Human RPE cell line, were treated with d-glucose (50 mM) to induce apoptosis in vitro. Prior to glucose, ARPE-19 cells were pre-incubated with various concentrations of DHF. The effect of DHF on d-glucose-induced apoptosis was examined by TUNEL assay, in a concentration-dependent manner. The biological effects of DHF on Caspase-9 (Casp-9) and TrkB signaling pathways in d-glucose-injured ARPE-19 cells were evaluated by qRT-PCR and western blot (WB) assays. A TrkB antagonist, K252a, was also applied in DHF and d-glucose treated ARPE-19 cells. Possible effect of K252a blocking TrkB signaling pathway, thus reversing DHF-modulated apoptosis prevention was also examined by TUNEL and WB assays. DHF ameliorated d-glucose-induced diabetic apoptosis in ARPE-19 cells. Apoptotic factor Casp-9, at both mRNA and protein levels, were drastically inhibited by DHF in d-glucose-injured ARPE-19 cells. Also, DHF activated TrkB signaling pathway through phosphorylation. K252a dramatically reversed the preventive effect of DHF on d-glucose-induced apoptosis in ARPE-19 cells. Further investigation showed that K252a functioned through de-activating or de-phosphorylating TrkB signaling pathway. This work demonstrates that DHF, through activation of TrkB signaling pathway, has a preventive function in d-glucose-induced apoptosis in PRE cells in diabetic retinopathy. Copyright © 2017. Published by Elsevier Inc.

  16. Human innate lymphoid cells

    NARCIS (Netherlands)

    Hazenberg, Mette D.; Spits, Hergen

    2014-01-01

    Innate lymphoid cells (ILCs) are lymphoid cells that do not express rearranged receptors and have important effector and regulatory functions in innate immunity and tissue remodeling. ILCs are categorized into 3 groups based on their distinct patterns of cytokine production and the requirement of

  17. Human innate lymphoid cells

    NARCIS (Netherlands)

    Mjösberg, Jenny; Spits, Hergen

    2016-01-01

    Innate lymphoid cells (ILCs) are increasingly acknowledged as important mediators of immune homeostasis and pathology. ILCs act as early orchestrators of immunity, responding to epithelium-derived signals by expressing an array of cytokines and cell-surface receptors, which shape subsequent immune

  18. RPE and RPO in the revised Swiss radiation protection legislation; RPE und RPO in der revidierten schweizerischen Strahlenschutzgesetzgebung

    Energy Technology Data Exchange (ETDEWEB)

    Jahn, S.G. [Eidgenoessisches Nuklearsicherheitsinspektorat (ENSI), Brugg (Switzerland); Stritt, N.; Bogni, S. [Bundesamt fuer Gesundheit (BAG), Bern (Switzerland); Hammans, M. [Schweizerische Unfallversicherungsanstalt (SUVA), Luzern (Switzerland); Duerst, B. [Departement fuer Verteidigung, Bevoelkerungsschutz und Sport (VBS), Bern (Switzerland); Kuehne, G. [Paul-Scherrer-Institut (PSI), Wuerenlingen (Switzerland); Besancon, A. [Institut de Radiophysique (IRA), Lausanne (Switzerland)

    2013-07-01

    Currently the Swiss 'Ordinance on Radiation Protection' and the 'Ordinance about Education and Training in RP' are undergoing a revision process. Concerning responsibilities and obligations as well as the capabilities and skills in RP the new ordinances are supposed to take account on the new EU Basic Safety Standard on the one hand and on the other hand to resume the approved approaches on RP in Switzerland. An overview of the planned content of the revised ordinances will be given in this report. In the Swiss system the education, training and retraining of RPO has a higher priority. Particularly it will be described which groups of persons assume the roles of RPE and therefore the definition of RPE in the new Swiss legislation is needless. (orig.)

  19. Suppression of topoisomerase IIα expression and function in human cells decreases chromosomal radiosensitivity

    International Nuclear Information System (INIS)

    Terry, Samantha Y.A.; Riches, Andrew C.; Bryant, Peter E.

    2009-01-01

    The mechanism behind chromatid break formation is as yet unclear, although it is known that DNA double-strand breaks (DSBs) are the initiating lesions. Chromatid breaks formed in cells in the G2-phase of the cell-cycle disappear ('rejoin') as a function of time between radiation exposure and cell fixation. However, the kinetics of disappearance of chromatid breaks does not correspond to those of DSB rejoining, leading us to seek alternative models. We have proposed that chromatid breaks could be formed indirectly from DSB and that the mechanism involves topoisomerase IIα. In support of this hypothesis we have recently shown that frequencies of radiation-induced chromatid breaks are lower in two variant human promyelocytic leukaemic cell lines with reduced topoisomerase IIα expression. Here we report that suppression of topoisomerase IIα in human hTERT-RPE1 cells, either by its abrogation using specific siRNA or by inhibition of its catalytic activity with the inhibitor ICRF-193, causes a reduction in frequency of chromatid breaks in radiation-exposed cells. The findings support our hypothesis for the involvement of topoisomerase IIα in the formation of radiation-induced chromatid breaks, and could help explain inter-individual variation in human chromosomal radiosensitivity; elevation of which has been linked with cancer susceptibility.

  20. Stimulated human fibroblast cell survival

    International Nuclear Information System (INIS)

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

    1992-01-01

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

  1. Induction of oxidative and nitrosative stresses in human retinal pigment epithelial cells by all-trans-retinal

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xue [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu Province (China); Wang, Ke, E-mail: wangke@jsinm.org [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu Province (China); Zhang, Kai [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu Province (China); Zhou, Fanfan [Faculty of Pharmacy, University of Sydney, New South Wales 2006 (Australia); Zhu, Ling [Save Sight Institute, University of Sydney, New South Wales 2000 (Australia)

    2016-10-15

    Delayed clearance of free form all-trans-retinal (atRAL) is estimated be the key cause of retinal pigment epithelium (RPE) cells injury during the pathogenesis of retinopathies such as age-related macular degeneration (AMD), however, the underlying molecular mechanisms are far from clear. In this study, we investigated the cytotoxicity effect and underlying molecular mechanism of atRAL on human retinal pigment epithelium ARPE-19 cells. The results indicated that atRAL could cause cell dysfunction by inducing oxidative and nitrosative stresses in ARPE-19 cells. The oxidative stress induced by atRAL was mediated through up-regulation of reactive oxygen species (ROS) generation, activating mitochondrial-dependent and MAPKs signaling pathways, and finally resulting in apoptosis of ARPE-19 cells. The NADPH oxidase inhibitor apocynin could partly attenuated ROS generation, indicating that NADPH oxidase activity was involved in atRAL-induced oxidative stress in ARPE-19 cells. The nitrosative stress induced by atRAL was mainly reflected in increasing nitric oxide (NO) production, enhancing iNOS, ICAM-1 and VCAM-1 expressions, and promoting monocyte adhesion. Furthermore, above effects could be dramatically blocked by using a nuclear factor kappa B (NF-κB) inhibitor SN50, indicated that atRAL-induced oxidative and nitrosative stresses were mediated by NF-κB. The results provide better understanding of atRAL-induced toxicity in human RPE cells. - Highlights: • atRAL induces oxidative stress-mediated apoptosis in ARPE-19 cells. • atRAL induces oxidative stress-mediated inflammation in ARPE-19 cells. • NF-κB is involved in atRAL-induced oxidative and nitrosative stresses.

  2. Induction of oxidative and nitrosative stresses in human retinal pigment epithelial cells by all-trans-retinal

    International Nuclear Information System (INIS)

    Zhu, Xue; Wang, Ke; Zhang, Kai; Zhou, Fanfan; Zhu, Ling

    2016-01-01

    Delayed clearance of free form all-trans-retinal (atRAL) is estimated be the key cause of retinal pigment epithelium (RPE) cells injury during the pathogenesis of retinopathies such as age-related macular degeneration (AMD), however, the underlying molecular mechanisms are far from clear. In this study, we investigated the cytotoxicity effect and underlying molecular mechanism of atRAL on human retinal pigment epithelium ARPE-19 cells. The results indicated that atRAL could cause cell dysfunction by inducing oxidative and nitrosative stresses in ARPE-19 cells. The oxidative stress induced by atRAL was mediated through up-regulation of reactive oxygen species (ROS) generation, activating mitochondrial-dependent and MAPKs signaling pathways, and finally resulting in apoptosis of ARPE-19 cells. The NADPH oxidase inhibitor apocynin could partly attenuated ROS generation, indicating that NADPH oxidase activity was involved in atRAL-induced oxidative stress in ARPE-19 cells. The nitrosative stress induced by atRAL was mainly reflected in increasing nitric oxide (NO) production, enhancing iNOS, ICAM-1 and VCAM-1 expressions, and promoting monocyte adhesion. Furthermore, above effects could be dramatically blocked by using a nuclear factor kappa B (NF-κB) inhibitor SN50, indicated that atRAL-induced oxidative and nitrosative stresses were mediated by NF-κB. The results provide better understanding of atRAL-induced toxicity in human RPE cells. - Highlights: • atRAL induces oxidative stress-mediated apoptosis in ARPE-19 cells. • atRAL induces oxidative stress-mediated inflammation in ARPE-19 cells. • NF-κB is involved in atRAL-induced oxidative and nitrosative stresses.

  3. Defining the Human Macula Transcriptome and Candidate Retinal Disease Genes UsingEyeSAGE

    Science.gov (United States)

    Rickman, Catherine Bowes; Ebright, Jessica N.; Zavodni, Zachary J.; Yu, Ling; Wang, Tianyuan; Daiger, Stephen P.; Wistow, Graeme; Boon, Kathy; Hauser, Michael A.

    2009-01-01

    Purpose To develop large-scale, high-throughput annotation of the human macula transcriptome and to identify and prioritize candidate genes for inherited retinal dystrophies, based on ocular-expression profiles using serial analysis of gene expression (SAGE). Methods Two human retina and two retinal pigment epithelium (RPE)/choroid SAGE libraries made from matched macula or midperipheral retina and adjacent RPE/choroid of morphologically normal 28- to 66-year-old donors and a human central retina longSAGE library made from 41- to 66-year-old donors were generated. Their transcription profiles were entered into a relational database, EyeSAGE, including microarray expression profiles of retina and publicly available normal human tissue SAGE libraries. EyeSAGE was used to identify retina- and RPE-specific and -associated genes, and candidate genes for retina and RPE disease loci. Differential and/or cell-type specific expression was validated by quantitative and single-cell RT-PCR. Results Cone photoreceptor-associated gene expression was elevated in the macula transcription profiles. Analysis of the longSAGE retina tags enhanced tag-to-gene mapping and revealed alternatively spliced genes. Analysis of candidate gene expression tables for the identified Bardet-Biedl syndrome disease gene (BBS5) in the BBS5 disease region table yielded BBS5 as the top candidate. Compelling candidates for inherited retina diseases were identified. Conclusions The EyeSAGE database, combining three different gene-profiling platforms including the authors’ multidonor-derived retina/RPE SAGE libraries and existing single-donor retina/RPE libraries, is a powerful resource for definition of the retina and RPE transcriptomes. It can be used to identify retina-specific genes, including alternatively spliced transcripts and to prioritize candidate genes within mapped retinal disease regions. PMID:16723438

  4. Human embryonic stem cells handbook

    Directory of Open Access Journals (Sweden)

    Carlo Alberto Redi

    2013-03-01

    Full Text Available After the Nobel prize in physiology or medicine was awarded jointly to Sir John Gurdon and Shinya Yamanaka for the discovery that mature cells can be reprogrammed to become pluripotent it became imperative to write down the review for a book entirely devoted to human embryonic stem cells (hES, those cells that are a urgent need for researchers, those cells that rekindle the ethical debates and finally, last but not least, those cells whose study paved the way to obtain induced pluripotent stem cells by the OSKC’s Yamanaka method (the OSKC acronim refers, for those not familiar with the topic, to the four stemness genes used to transfect somatic fibroblasts: Oct4, Sox2, Klf4 and c-Myc....

  5. Collectin-11 Is an Important Modulator of Retinal Pigment Epithelial Cell Phagocytosis and Cytokine Production.

    Science.gov (United States)

    Dong, Xia; Wu, Weiju; Ma, Liang; Liu, Chengfei; Bhuckory, Mohajeet B; Wang, Liping; Nandrot, Emeline F; Xu, Heping; Li, Ke; Liu, Yizhi; Zhou, Wuding

    2017-01-01

    In this paper, we report previously unknown roles for collectin-11 (CL-11, a soluble C-type lectin) in modulating the retinal pigment epithelial (RPE) cell functions of phagocytosis and cytokine production. We found that CL-11 and its carbohydrate ligand are expressed in both the murine and human neural retina; these resemble each other in terms of RPE and photoreceptor cells. Functional analysis of murine RPE cells showed that CL-11 facilitates the opsonophagocytosis of photoreceptor outer segments and apoptotic cells, and also upregulates IL-10 production. Mechanistic analysis revealed that calreticulin on the RPE cells is required for CL-11-mediated opsonophagocytosis whereas signal-regulatory protein α and mannosyl residues on the cells are involved in the CL-11-mediated upregulation of IL-10 production. This study is the first to demonstrate the role of CL-11 and the molecular mechanisms involved in modulating RPE cell phagocytosis and cytokine production. It provides a new insight into retinal health and disease and has implications for other phagocytic cells. © 2017 S. Karger AG, Basel.

  6. Altered bioenergetics and enhanced resistance to oxidative stress in human retinal pigment epithelial cells from donors with age-related macular degeneration

    Directory of Open Access Journals (Sweden)

    Deborah A. Ferrington

    2017-10-01

    Full Text Available Age-related macular degeneration (AMD is the leading cause of blindness among older adults. It has been suggested that mitochondrial defects in the retinal pigment epithelium (RPE underlies AMD pathology. To test this idea, we developed primary cultures of RPE to ask whether RPE from donors with AMD differ in their metabolic profile compared with healthy age-matched donors. Analysis of gene expression, protein content, and RPE function showed that these cultured cells replicated many of the cardinal features of RPE in vivo. Using the Seahorse Extracellular Flux Analyzer to measure bioenergetics, we observed RPE from donors with AMD exhibited reduced mitochondrial and glycolytic function compared with healthy donors. RPE from AMD donors were also more resistant to oxidative inactivation of these two energy-producing pathways and were less susceptible to oxidation-induced cell death compared with cells from healthy donors. Investigation of the potential mechanism responsible for differences in bioenergetics and resistance to oxidative stress showed RPE from AMD donors had increased PGC1α protein as well as differential expression of multiple genes in response to an oxidative challenge. Based on our data, we propose that cultured RPE from donors phenotyped for the presence or absence of AMD provides an excellent model system for studying “AMD in a dish”. Our results are consistent with the ideas that (i a bioenergetics crisis in the RPE contributes to AMD pathology, and (ii the diseased environment in vivo causes changes in the cellular profile that are retained in vitro.

  7. Functional annotation of the human retinal pigment epithelium transcriptome

    Directory of Open Access Journals (Sweden)

    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

  8. Identification of intracellular phospholipases A2 in the human eye: involvement in phagocytosis of photoreceptor outer segments

    DEFF Research Database (Denmark)

    Kolko, Miriam; Wang, Jinmei; Zhan, Chen

    2007-01-01

    PURPOSE: To identify intracellular phospholipases A(2) (PLA(2)) in the human retina and to explore the role of these enzymes in human retinal pigment epithelium (RPE) phagocytosis of photoreceptor outer segments (POS). METHODS: PCR amplification and Western blot analysis were used to identify m......)-VIA activity was found to be specifically increased 12 hours after ARPE-19 cells were fed with POS. Finally, RPE phagocytosis was inhibited by the iPLA(2)-VIA inhibitor bromoenol lactone. CONCLUSIONS: Various intracellular PLA(2) subtypes are present in the human retina. iPLA(2)-VIA may play...

  9. Tuft (caveolated) cells in two human colon carcinoma cell lines.

    OpenAIRE

    Barkla, D. H.; Whitehead, R. H.; Foster, H.; Tutton, P. J.

    1988-01-01

    The presence of an unusual cell type in two human colon carcinoma cell lines is reported. The cells show the same morphology as "tuft" (caveolated) cells present in normal gastrointestinal epithelium. Tuft cells were seen in cell line LIM 1863 growing in vitro and in human colon carcinoma cell line LIM 2210 growing as subcutaneous solid tumour xenografts in nude mice. Characteristic morphologic features of tuft cells included a wide base, narrow apex and a tuft of long microvilli projecting f...

  10. Combination of retinal pigment epithelium cell-conditioned medium and photoreceptor outer segments stimulate mesenchymal stem cell differentiation toward a functional retinal pigment epithelium cell phenotype.

    Science.gov (United States)

    Huang, Chen; Zhang, Jing; Ao, Mingxin; Li, Ying; Zhang, Chun; Xu, Yonggen; Li, Xuemin; Wang, Wei

    2012-02-01

    Recent studies have suggested that bone marrow-derived mesenchymal stem cells (BMMSCs) are capable of retinal tissue-specific differentiation but not retinal pigment epithelium (RPE) cell-specific differentiation. Photoreceptor outer segments (POS) contribute to RPE development and maturation. However, there has been no standard culture system that fosters the differentiation of BMMSCs into mature RPE cells in vitro. In this study, we investigated if the soluble factors from RPE cells and POS could differentiate BMMSCs into cells having a phenotype characteristic of RPE cells. Rat BMMSCs were separately co-cultured with RPE cells, or they were exposed to either control medium, RPE cell-conditioned medium (RPECM), POS, or a combination of RPECM and POS (RPECM-POS). After 7 days, the cells were analyzed for morphology and the expression of RPE markers (cytokeratin 8, CRALBP, and RPE65) to assess the RPE differentiation. Significantly higher pigment accumulation and increased protein expression of the three markers were seen in cells cultured in RPECM-POS than in other treated cultures. Furthermore, the RPECM-POS-treated cultures displayed ultrastructural features typical of RPE cells, expressed RPE cell functional proteins, and had the capability to phagocytose POS. Together, theses results suggest the combination of RPECM and POS stimulate BMMSCs differentiation toward a functional RPE phenotype. Our results provide the foundation for a new route to RPE regenerative therapy involving BMMSCs. Future work isolating the active agent in RPECM and POS would be useful in therapies for RPE diseases or in developing appropriately pre-differentiated BMMSCs for tissue-engineered RPE reconstruction. Copyright © 2011 Wiley Periodicals, Inc.

  11. Human glomerular epithelial cell proteoglycans

    International Nuclear Information System (INIS)

    Thomas, G.J.; Jenner, L.; Mason, R.M.; Davies, M.

    1990-01-01

    Proteoglycans synthesized by cultures of human glomerular epithelial cells have been isolated and characterized. Three types of heparan sulfate were detected. Heparan sulfate proteoglycan I (HSPG-I; Kav 6B 0.04) was found in the cell layer and medium and accounted for 12% of the total proteoglycans synthesized. HSPG-II (Kav 6B 0.25) accounted for 18% of the proteoglycans and was located in the medium and cell layer. A third population (9% of the proteoglycan population), heparan sulfate glycosaminoglycan (HS-GAG; Kav 6B 0.4-0.8), had properties consistent with single glycosaminoglycan chains or their fragments and was found only in the cell layer. HSPG-I and HSPG-II from the cell layer had hydrophobic properties; they were released from the cell layer by mild trypsin treatment. HS-GAG lacked these properties, consisted of low-molecular-mass heparan sulfate oligosaccharides, and were intracellular. HSPG-I and -II released to the medium lacked hydrophobic properties. The cells also produced three distinct types of chondroitin sulfates. The major species, chondroitin sulfate proteoglycan I (CSPG-I) eluted in the excluded volume of a Sepharose CL-6B column, accounted for 30% of the proteoglycans detected, and was found in both the cell layer and medium. Cell layer CSPG-I bound to octyl-Sepharose. It was released from the cell layer by mild trypsin treatment. CSPG-II (Kav 6B 0.1-0.23) accounted for 10% of the total 35S-labeled macromolecules and was found predominantly in the culture medium. A small amount of CS-GAG (Kav 6B 0.25-0.6) is present in the cell extract and like HS-GAG is intracellular. Pulse-chase experiments indicated that HSPG-I and -II and CSPG-I and -II are lost from the cell layer either by direct release into the medium or by internalization where they are metabolized to single glycosaminoglycan chains and subsequently to inorganic sulfate

  12. DNA repair in human cells

    International Nuclear Information System (INIS)

    Regan, J.D.; Carrier, W.L.; Kusano, I.; Furuno-Fukushi, I.; Dunn, W.C. Jr.; Francis, A.A.; Lee, W.H.

    1982-01-01

    Our primary objective is to elucidate the molecular events in human cells when cellular macromolecules such as DNA are damaged by radiation or chemical agents. We study and characterize (i) the sequence of DNA repair events, (ii) the various modalities of repair, (iii) the genetic inhibition of repair due to mutation, (iv) the physiological inhibition of repair due to mutation, (v) the physiological inhibition of repair due to biochemical inhibitors, and (vi) the genetic basis of repair. Our ultimate goals are to (i) isolate and analyze the repair component of the mutagenic and/or carcinogenic event in human cells, and (ii) elucidate the magnitude and significance of this repair component as it impinges on the practical problems of human irradiation or exposure to actual or potential chemical mutagens and carcinogens. The significance of these studies lies in (i) the ubiquitousness of repair (most organisms, including man, have several complex repair systems), (ii) the belief that mutagenic and carcinogenic events may arise only from residual (nonrepaired) lesions or that error-prone repair systems may be the major induction mechanisms of the mutagenic or carcinogenic event, and (iii) the clear association of repair defects and highly carcinogenic disease states in man [xeroderma pigmentosum (XP)

  13. The human airway epithelial basal cell transcriptome.

    Directory of Open Access Journals (Sweden)

    Neil R Hackett

    2011-05-01

    Full Text Available The human airway epithelium consists of 4 major cell types: ciliated, secretory, columnar and basal cells. During natural turnover and in response to injury, the airway basal cells function as stem/progenitor cells for the other airway cell types. The objective of this study is to better understand human airway epithelial basal cell biology by defining the gene expression signature of this cell population.Bronchial brushing was used to obtain airway epithelium from healthy nonsmokers. Microarrays were used to assess the transcriptome of basal cells purified from the airway epithelium in comparison to the transcriptome of the differentiated airway epithelium. This analysis identified the "human airway basal cell signature" as 1,161 unique genes with >5-fold higher expression level in basal cells compared to differentiated epithelium. The basal cell signature was suppressed when the basal cells differentiated into a ciliated airway epithelium in vitro. The basal cell signature displayed overlap with genes expressed in basal-like cells from other human tissues and with that of murine airway basal cells. Consistent with self-modulation as well as signaling to other airway cell types, the human airway basal cell signature was characterized by genes encoding extracellular matrix components, growth factors and growth factor receptors, including genes related to the EGF and VEGF pathways. Interestingly, while the basal cell signature overlaps that of basal-like cells of other organs, the human airway basal cell signature has features not previously associated with this cell type, including a unique pattern of genes encoding extracellular matrix components, G protein-coupled receptors, neuroactive ligands and receptors, and ion channels.The human airway epithelial basal cell signature identified in the present study provides novel insights into the molecular phenotype and biology of the stem/progenitor cells of the human airway epithelium.

  14. Guanine nucleotide-binding regulatory proteins in retinal pigment epithelial cells.

    OpenAIRE

    Jiang, M; Pandey, S; Tran, V T; Fong, H K

    1991-01-01

    The expression of GTP-binding regulatory proteins (G proteins) in retinal pigment epithelial (RPE) cells was analyzed by RNA blot hybridization and cDNA amplification. Both adult and fetal human RPE cells contain mRNA for multiple G protein alpha subunits (G alpha) including Gs alpha, Gi-1 alpha, Gi-2 alpha, Gi-3 alpha, and Gz alpha (or Gx alpha), where Gs and Gi are proteins that stimulate or inhibit adenylyl cyclase, respectively, and Gz is a protein that may mediate pertussis toxin-insensi...

  15. Evidence for RPE65-independent vision in the cone-dominated zebrafish retina.

    Science.gov (United States)

    Schonthaler, Helia B; Lampert, Johanna M; Isken, Andrea; Rinner, Oliver; Mader, Andreas; Gesemann, Matthias; Oberhauser, Vitus; Golczak, Marcin; Biehlmaier, Oliver; Palczewski, Krzysztof; Neuhauss, Stephan C F; von Lintig, Johannes

    2007-10-01

    An enzyme-based cyclic pathway for trans to cis isomerization of the chromophore of visual pigments (11-cis-retinal) is intrinsic to vertebrate cone and rod vision. This process, called the visual cycle, is mostly characterized in rod-dominated retinas and essentially depends on RPE65, an all-trans to 11-cis-retinoid isomerase. Here we analysed the role of RPE65 in zebrafish, a species with a cone-dominated retina. We cloned zebrafish RPE65 and showed that its expression coincided with photoreceptor development. Targeted gene knockdown of RPE65 resulted in morphologically altered rod outer segments and overall reduced 11-cis-retinal levels. Cone vision of RPE65-deficient larvae remained functional as demonstrated by behavioural tests and by metabolite profiling for retinoids. Furthermore, all-trans retinylamine, a potent inhibitor of the rod visual cycle, reduced 11-cis-retinal levels of control larvae to a similar extent but showed no additive effects in RPE65-deficient larvae. Thus, our study of zebrafish provides in vivo evidence for the existence of an RPE65-independent pathway for the regeneration of 11-cis-retinal for cone vision.

  16. Human regulatory B cells control the TFH cell response.

    Science.gov (United States)

    Achour, Achouak; Simon, Quentin; Mohr, Audrey; Séité, Jean-François; Youinou, Pierre; Bendaoud, Boutahar; Ghedira, Ibtissem; Pers, Jacques-Olivier; Jamin, Christophe

    2017-07-01

    Follicular helper T (T FH ) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of T FH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on T FH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate T FH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing T FH cell maturation. In cocultures they differentiated B cells into CD138 + plasma and IgD - CD27 + memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented T FH cell development. Added to T FH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3 + CXCR5 + PD-1 + follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on T FH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Human Breg cells control T FH cell maturation, expand follicular regulatory T cells, and inhibit the T FH cell-mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the T FH cell-dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  17. Alanine/RPE dosimetry in the process of blood irradiation

    International Nuclear Information System (INIS)

    Chen, F.; Covas, D.T.; Baffa, O.

    2000-01-01

    A set of eighty dosemeters approximately of Dl- alanine was proportioned to the Hemo center of Hospital das Clinicas of Medicine Faculty at Ribeirao Preto (HC-FRMP) in the Sao Paulo University, with the purpose to realize a quality control of the radiation dose supplied to blood bags. These dosemeters were divided in eight groups and irradiated for a two months period.The dosemeters were adhered to the bags and arranged inside of an acrylic box filled water with dimensions: (40x40x20) cm 3 . The box irradiation was made using two fields parallel-opposed of (40x40) cm 2 at 80 cm distance source-surface, in the Radiotherapy Service of HC-FMRP, with a 60 Co teletherapy unit. The irradiation time was sufficient to supply a dose of 20 Gy approximately in the box center. The RPE measures were realized in a Varian E-4 spectrometer operating in X-band. For the total of dosemeters and for the irradiation volume, the minimum and maximum doses were of 14 Gy and 23 Gy respectively. The mean dose was (18±2) Gy (1 σ), and the variability coefficient 11 %. Around 5 % of the bags received a dose under of the recommended limit by the Brazilian legislation and as consequence, the exposure time was increased. (Author)

  18. Session-RPE Method for Training Load Monitoring: Validity, Ecological Usefulness, and Influencing Factors

    Directory of Open Access Journals (Sweden)

    Monoem Haddad

    2017-11-01

    Full Text Available Purpose: The aim of this review is to (1 retrieve all data validating the Session-rating of perceived exertion (RPE-method using various criteria, (2 highlight the rationale of this method and its ecological usefulness, and (3 describe factors that can alter RPE and users of this method should take into consideration.Method: Search engines such as SPORTDiscus, PubMed, and Google Scholar databases in the English language between 2001 and 2016 were consulted for the validity and usefulness of the session-RPE method. Studies were considered for further analysis when they used the session-RPE method proposed by Foster et al. in 2001. Participants were athletes of any gender, age, or level of competition. Studies using languages other than English were excluded in the analysis of the validity and reliability of the session-RPE method. Other studies were examined to explain the rationale of the session-RPE method and the origin of RPE.Results: A total of 950 studies cited the Foster et al. study that proposed the session RPE-method. 36 studies have examined the validity and reliability of this proposed method using the modified CR-10.Conclusion: These studies confirmed the validity and good reliability and internal consistency of session-RPE method in several sports and physical activities with men and women of different age categories (children, adolescents, and adults among various expertise levels. This method could be used as “standing alone” method for training load (TL monitoring purposes though some recommend to combine it with other physiological parameters as heart rate.

  19. Endocannabinoids and Human Sperm Cells

    Directory of Open Access Journals (Sweden)

    Giovanna Zolese

    2010-10-01

    Full Text Available N-acylethanolamides (NAEs are naturally occurring signaling lipids consisting of amides and esters of long-chain polyunsaturated fatty acids. Usually they are present in a very small amounts in many mammalian tissues and cells, including human reproductive tracts and fluids. Recently, the presence of N-arachidonoylethanolamide (anandamide, AEA, the most characterised member of endocannabinoids, and its congeners palmitoylethanolamide (PEA and oleylethanolamide (OEA in seminal plasma, oviductal fluid, and follicular fluids was demonstrated. AEA has been shown to bind not only type-1 (CB1 and type-2 (CB2 cannabinoid receptors, but also type-1 vanilloid receptor (TRPV1, while PEA and OEA are inactive with respect to classical cannabinoid CB1 and CB2 but activate TRPV1 or peroxisome proliferator activate receptors (PPARs. This review concerns the most recent experimental data on PEA and OEA, endocannabinoid-like molecules which appear to exert their action exclusively on sperm cells with altered features, such as membrane characteristics and kinematic parameters. Their beneficial effects on these cells could suggest a possible pharmacological use of PEA and OEA on patients affected by some forms of idiopathic infertility.

  20. Isolation and characterization of a spontaneously immortalized bovine retinal pigmented epithelial cell line

    Directory of Open Access Journals (Sweden)

    Griffiths T Daniel

    2009-05-01

    Full Text Available Abstract Background The Retinal Pigmented Epithelium (RPE is juxtaposed with the photoreceptor outer segments of the eye. The proximity of the photoreceptor cells is a prerequisite for their survival, as they depend on the RPE to remove the outer segments and are also influenced by RPE cell paracrine factors. RPE cell death can cause a progressive loss of photoreceptor function, which can diminish vision and, over time, blindness ensues. Degeneration of the retina has been shown to induce a variety of retinopathies, such as Stargardt's disease, Cone-Rod Dystrophy (CRD, Retinitis Pigmentosa (RP, Fundus Flavimaculatus (FFM, Best's disease and Age-related Macular Degeneration (AMD. We have cultured primary bovine RPE cells to gain a further understanding of the mechanisms of RPE cell death. One of the cultures, named tRPE, surpassed senescence and was further characterized to determine its viability as a model for retinal diseases. Results The tRPE cell line has been passaged up to 150 population doublings and was shown to be morphologically similar to primary cells. They have been characterized to be of RPE origin by reverse transcriptase PCR and immunocytochemistry using the RPE-specific genes RPE65 and CRALBP and RPE-specific proteins RPE65 and Bestrophin. The tRPE cells are also immunoreactive to vimentin, cytokeratin and zonula occludens-1 antibodies. Chromosome analysis indicates a normal diploid number. The tRPE cells do not grow in suspension or in soft agar. After 3H thymidine incorporation, the cells do not appear to divide appreciably after confluency. Conclusion The tRPE cells are immortal, but still exhibit contact inhibition, serum dependence, monolayer growth and secrete an extra-cellular matrix. They retain the in-vivo morphology, gene expression and cell polarity. Additionally, the cells endocytose exogenous melanin, A2E and purified lipofuscin granules. This cell line may be a useful in-vitro research model for retinal

  1. Stem cells in the human breast

    DEFF Research Database (Denmark)

    Petersen, Ole William; Polyak, Kornelia

    2010-01-01

    The origins of the epithelial cells participating in the development, tissue homeostasis, and cancer of the human breast are poorly understood. However, emerging evidence suggests a role for adult tissue-specific stem cells in these processes. In a hierarchical manner, these generate the two main...... mammary cell lineages, producing an increasing number of cells with distinct properties. Understanding the biological characteristics of human breast stem cells and their progeny is crucial in attempts to compare the features of normal stem cells and cancer precursor cells and distinguish these from...... nonprecursor cells and cells from the bulk of a tumor. A historical overview of research on human breast stem cells in primary tissue and in culture reveals the progress that has been made in this area, whereas a focus on the cell-of-origin and reprogramming that occurs during neoplastic conversion provides...

  2. Satellite cells in human skeletal muscle plasticity.

    Science.gov (United States)

    Snijders, Tim; Nederveen, Joshua P; McKay, Bryon R; Joanisse, Sophie; Verdijk, Lex B; van Loon, Luc J C; Parise, Gianni

    2015-01-01

    Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodeling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to humans under physiological conditions. Findings from in vivo human studies suggest that satellite cells play a key role in skeletal muscle fiber repair/remodeling in response to exercise. Mounting evidence indicates that aging has a profound impact on the regulation of satellite cells in human skeletal muscle. Yet, the precise role of satellite cells in the development of muscle fiber atrophy with age remains unresolved. This review seeks to integrate recent results from in vivo human studies on satellite cell function in muscle fiber repair/remodeling in the wider context of satellite cell biology whose literature is largely based on animal and cell models.

  3. Differentiation/Purification Protocol for Retinal Pigment Epithelium from Mouse Induced Pluripotent Stem Cells as a Research Tool.

    Directory of Open Access Journals (Sweden)

    Yuko Iwasaki

    Full Text Available To establish a novel protocol for differentiation of retinal pigment epithelium (RPE with high purity from mouse induced pluripotent stem cells (iPSC.Retinal progenitor cells were differentiated from mouse iPSC, and RPE differentiation was then enhanced by activation of the Wnt signaling pathway, inhibition of the fibroblast growth factor signaling pathway, and inhibition of the Rho-associated, coiled-coil containing protein kinase signaling pathway. Expanded pigmented cells were purified by plate adhesion after Accutase® treatment. Enriched cells were cultured until they developed a cobblestone appearance with cuboidal shape. The characteristics of iPS-RPE were confirmed by gene expression, immunocytochemistry, and electron microscopy. Functions and immunologic features of the iPS-RPE were also evaluated.We obtained iPS-RPE at high purity (approximately 98%. The iPS-RPE showed apical-basal polarity and cellular structure characteristic of RPE. Expression levels of several RPE markers were lower than those of freshly isolated mouse RPE but comparable to those of primary cultured RPE. The iPS-RPE could form tight junctions, phagocytose photoreceptor outer segments, express immune antigens, and suppress lymphocyte proliferation.We successfully developed a differentiation/purification protocol to obtain mouse iPS-RPE. The mouse iPS-RPE can serve as an attractive tool for functional and morphological studies of RPE.

  4. Loss of Melanin by Eye Retinal Pigment Epithelium Cells Is Associated with Its Oxidative Destruction in Melanolipofuscin Granules.

    Science.gov (United States)

    Dontsov, A E; Sakina, N L; Ostrovsky, M A

    2017-08-01

    The effect of superoxide radicals on melanin destruction and degradation of melanosomes isolated from cells of retinal pigment epithelium (RPE) of the human eye was studied. We found that potassium superoxide causes destruction of melanin in melanosomes of human and bovine RPE, as well as destruction of melanin from the ink bag of squid, with the formation of fluorescent decay products having an emission maximum at 520-525 nm. The initial kinetics of the accumulation of the fluorescent decay products is linear. Superoxide radicals lead simultaneously to a decrease in the number of melanosomes and to a decrease in concentration of paramagnetic centers in them. Complete degradation of melanosomes leads to the formation of a transparent solution containing dissolved proteins and melanin degradation products that do not exhibit paramagnetic properties. To completely degrade one melanosome of human RPE, 650 ± 100 fmol of superoxide are sufficient. The concentration of paramagnetic centers in a melanolipofuscin granule of human RPE is on average 32.5 ± 10.4% (p melanin undergoing a destruction process in these granules. RPE cells also contain intermediate granules that have an EPR signal with a lower intensity than that of melanolipofuscin granules, but higher than that of lipofuscin granules. This signal is due to the presence of residual melanin in these granules. Irradiation of a mixture of melanosomes with lipofuscin granules with blue light (450 nm), in contrast to irradiation of only melanosomes, results in the appearance of fluorescent melanin degradation products. We suggest that one of the main mechanisms of age-related decrease in melanin concentration in human RPE cells is its destruction in melanolipofuscin granules under the action of superoxide radicals formed during photoinduced oxygen reduction by lipofuscin fluorophores.

  5. Epigallocatechin-gallate (EGCG) regulates autophagy in human retinal pigment epithelial cells: A potential role for reducing UVB light-induced retinal damage

    International Nuclear Information System (INIS)

    Li, Chao-Peng; Yao, Jin; Tao, Zhi-Fu; Li, Xiu-Miao; Jiang, Qin; Yan, Biao

    2013-01-01

    Highlights: •UVB irradiation induces RPE autophagy. •EGCG treatment represses UVB-mediated autophagy. •EGCG regulates UVB-mediated autophagy through mTOR signaling pathway. •EGCG sensitizes RPE cells to UVB-induced damage in an autophagy-dependent manner. -- Abstract: Autophagy is an intracellular catabolic process involved in protein and organelle degradation via the lysosomal pathway that has been linked in the pathogenesis of age-related macular degeneration (AMD). UVB irradiation-mediated degeneration of the macular retinal pigment epithelial (RPE) cells is an important hallmark of AMD, which is along with the change in RPE autophagy. Thus, pharmacological manipulation of RPE autophagy may offer an alternative therapeutic target in AMD. Here, we found that epigallocatechin-3-gallate (EGCG), a polyphenolic compound from green tea, plays a regulatory role in UVB irradiation-induced autophagy in RPE cells. UVB irradiation results in a marked increase in the amount of LC3-II protein in a dose-dependent manner. EGCG administration leads to a significant reduction in the formation of LC3-II and autophagosomes. mTOR signaling activation is required for EGCG-induced LC3-II formation, as evidenced by the fact that EGCG-induced LC3-II formation is significantly impaired by rapamycin administration. Moreover, EGCG significantly alleviates the toxic effects of UVB irradiation on RPE cells in an autophagy-dependent manner. Collectively, our study reveals a novel role of EGCG in RPE autophagy. EGCG may be exploited as a potential therapeutic reagent for the treatment of pathological conditions associated with abnormal autophagy

  6. Epigallocatechin-gallate (EGCG) regulates autophagy in human retinal pigment epithelial cells: A potential role for reducing UVB light-induced retinal damage

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chao-Peng; Yao, Jin; Tao, Zhi-Fu; Li, Xiu-Miao; Jiang, Qin, E-mail: jqin710@vip.sina.com; Yan, Biao, E-mail: yanbiao1982@hotmail.com

    2013-09-06

    Highlights: •UVB irradiation induces RPE autophagy. •EGCG treatment represses UVB-mediated autophagy. •EGCG regulates UVB-mediated autophagy through mTOR signaling pathway. •EGCG sensitizes RPE cells to UVB-induced damage in an autophagy-dependent manner. -- Abstract: Autophagy is an intracellular catabolic process involved in protein and organelle degradation via the lysosomal pathway that has been linked in the pathogenesis of age-related macular degeneration (AMD). UVB irradiation-mediated degeneration of the macular retinal pigment epithelial (RPE) cells is an important hallmark of AMD, which is along with the change in RPE autophagy. Thus, pharmacological manipulation of RPE autophagy may offer an alternative therapeutic target in AMD. Here, we found that epigallocatechin-3-gallate (EGCG), a polyphenolic compound from green tea, plays a regulatory role in UVB irradiation-induced autophagy in RPE cells. UVB irradiation results in a marked increase in the amount of LC3-II protein in a dose-dependent manner. EGCG administration leads to a significant reduction in the formation of LC3-II and autophagosomes. mTOR signaling activation is required for EGCG-induced LC3-II formation, as evidenced by the fact that EGCG-induced LC3-II formation is significantly impaired by rapamycin administration. Moreover, EGCG significantly alleviates the toxic effects of UVB irradiation on RPE cells in an autophagy-dependent manner. Collectively, our study reveals a novel role of EGCG in RPE autophagy. EGCG may be exploited as a potential therapeutic reagent for the treatment of pathological conditions associated with abnormal autophagy.

  7. c-Myc-Dependent Cell Competition in Human Cancer Cells.

    Science.gov (United States)

    Patel, Manish S; Shah, Heta S; Shrivastava, Neeta

    2017-07-01

    Cell Competition is an interaction between cells for existence in heterogeneous cell populations of multicellular organisms. This phenomenon is involved in initiation and progression of cancer where heterogeneous cell populations compete directly or indirectly for the survival of the fittest based on differential gene expression. In Drosophila, cells having lower dMyc expression are eliminated by cell competition through apoptosis when present in the milieu of cells having higher dMyc expression. Thus, we designed a study to develop c-Myc (human homolog) dependent in vitro cell competition model of human cancer cells. Cells with higher c-Myc were transfected with c-myc shRNA to prepare cells with lower c-Myc and then co-cultured with the same type of cells having a higher c-Myc in equal ratio. Cells with lower c-Myc showed a significant decrease in numbers when compared with higher c-Myc cells, suggesting "loser" and "winner" status of cells, respectively. During microscopy, engulfment of loser cells by winner cells was observed with higher expression of JNK in loser cells. Furthermore, elimination of loser cells was prevented significantly, when co-cultured cells were treated with the JNK (apoptosis) inhibitor. Above results indicate elimination of loser cells in the presence of winner cells by c-Myc-dependent mechanisms of cell competition in human cancer cells. This could be an important mechanism in human tumors where normal cells are eliminated by c-Myc-overexpressed tumor cells. J. Cell. Biochem. 118: 1782-1791, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Does the Timing of Measurement Alter Session-RPE in Boxers?

    Science.gov (United States)

    Uchida, Marco C; Teixeira, Luis F M; Godoi, Vladmir J; Marchetti, Paulo H; Conte, Marcelo; Coutts, Aaron J; Bacurau, Reury F P

    2014-01-01

    The purpose of this study was to compare the influence of measuring the overall session rating of perceived exertion (session-RPE) at 10 vs. 30 minutes following exercise. Eight boxers completed three different standardized training sessions of different intensities (easy, moderate and hard) in a matchedpairs, randomized research design. Exercise intensity was assessed during each bout by measuring heart rate, blood lactate concentration and session-RPE. To assess the effect of measurement timing on session-RPE, RPE data were collected either 10 or 30 minutes post-exercise. There was no significant effect of measurement time on session-RPE values following easy (10 minutes: session-RPE = 1.3 ± 1.0 Arbitrary Unit (AU), %Heart Rate Reserve (HRR) = 49.5 ± 11.1, and ∆Blood lactate = -2.3 ± 16.3%; 30 minutes: session-RPE = 1.7 ± 1.0 AU, %HRR = 51.3 ± 10.8, and ∆Blood lactate = 0.7 ± 25.2%), moderate (10 minutes: session-RPE = 2.7 ± 1.6 AU, %HRR = 67.2 ± 10.8, and ∆Blood lactate = 2.2 ± 19%; 30 minutes: session-RPE = 2.5 ± 0.9 AU, %HRR = 67.2 ± 5.9, and ∆Blood lactate = 24.5 ± 17.1%) and hard (10 minutes: session-RPE = 5.7 ± 1.0 AU, %HRR = 88.1 ± 6.3, and ∆Blood lactate = 146.3 ± 87.9%; 30 minutes: session-RPE = 5.8 ± 1.9 AU, %HRR> = 83.3 ± 8.0, and ∆Blood lactate = 91.6 ± 39%) sessions. In conclusion, our findings suggest that session-RPE can be used in boxing training routines across a range of intensities and accurate measurements can be determined as early as 10 minutes after exercise. Key PointsIt is difficult to quantify and monitoring the external training load in martial arts (e.g. Aikido, Kung Fu, Judo) and physical combat sports (e.g. Boxing, Muay Thai), session RPE method appears to be a reliable method to quantifying training load in those sports.For many athletes it is impractical to wait 30 minutes after training session to provide a session-RPE. The present findings show that collecting ses-sion-RPE measures at 10 min

  9. acute and session rPe responses during resistance training: Bouts ...

    African Journals Online (AJOL)

    tive measure of aerobic exercise intensity. While correlating well ... ing intensity in aerobic-type exercise. 7 ... While original work dealt with RPE during an exercise bout, ..... Borg G. Perceived exertion as an indicator of somatic stress. Scan J.

  10. Signaling hierarchy regulating human endothelial cell development.

    Science.gov (United States)

    Kelly, Melissa A; Hirschi, Karen K

    2009-05-01

    Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these studies. Using human embryonic stem cells as a model system, we were able to reproducibly and robustly generate differentiated endothelial cells via coculture on OP9 marrow stromal cells. We found that, in contrast to studies in the mouse, bFGF and VEGF had no specific effects on the initiation of human vasculogenesis. However, exogenous Ihh promoted endothelial cell differentiation, as evidenced by increased production of cells with cobblestone morphology that coexpress multiple endothelial-specific genes and proteins, form lumens, and exhibit DiI-AcLDL uptake. Inhibition of BMP signaling using Noggin or BMP4, specifically, using neutralizing antibodies suppressed endothelial cell formation; whereas, addition of rhBMP4 to cells treated with the hedgehog inhibitor cyclopamine rescued endothelial cell development. Our studies revealed that Ihh promoted human endothelial cell differentiation from pluripotent hES cells via BMP signaling, providing novel insights applicable to modulating human endothelial cell formation and vascular regeneration for human clinical therapies.

  11. Symmetry breaking in human neuroblastoma cells

    Science.gov (United States)

    Izumi, Hideki; Kaneko, Yasuhiko

    2014-01-01

    Asymmetric cell division (ACD) is a characteristic of cancer stem cells, which exhibit high malignant potential. However, the cellular mechanisms that regulate symmetric (self-renewal) and asymmetric cell divisions are mostly unknown. Using human neuroblastoma cells, we found that the oncosuppressor protein tripartite motif containing 32 (TRIM32) positively regulates ACD. PMID:27308367

  12. Trophoblast lineage cells derived from human induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying, E-mail: ying.chen@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Wang, Kai; Chandramouli, Gadisetti V.R. [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Knott, Jason G. [Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University (United States); Leach, Richard, E-mail: Richard.leach@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Department of Obstetrics, Gynecology and Women’s Health, Spectrum Health Medical Group (United States)

    2013-07-12

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro.

  13. Trophoblast lineage cells derived from human induced pluripotent stem cells

    International Nuclear Information System (INIS)

    Chen, Ying; Wang, Kai; Chandramouli, Gadisetti V.R.; Knott, Jason G.; Leach, Richard

    2013-01-01

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro

  14. Diffusion inside living human cells

    DEFF Research Database (Denmark)

    Leijnse, N.; Jeon, J. -H.; Loft, Steffen

    2012-01-01

    of the cell or within the nucleus. Also, granules in cells which are stressed by intense laser illumination or which have attached to a surface for a long period of time move in a more restricted fashion than those within healthy cells. For granules diffusing in healthy cells, in regions away from the cell...... cells. For these cells the exact diffusional pattern of a particular granule depends on the physiological state of the cell and on the localization of the granule within the cytoplasm. Granules located close to the actin rich periphery of the cell move less than those located towards to the center...

  15. Phototoxicity and cytotoxicity of fullerol in human retinal pigment epithelial cells

    International Nuclear Information System (INIS)

    Wielgus, Albert R.; Zhao, Baozhong; Chignell, Colin F.; Hu, Dan-Ning; Roberts, Joan E.

    2010-01-01

    The water-soluble nanoparticle hydroxylated fullerene [fullerol, nano-C 60 (OH) 22-26 ] has several clinical applications including use as a drug carrier to bypass the blood ocular barriers. We have previously found that fullerol is both cytotoxic and phototoxic to human lens epithelial cells (HLE B-3) and that the endogenous antioxidant lutein blocked some of this phototoxicity. In the present study we have found that fullerol induces cytotoxic and phototoxic damage to human retinal pigment epithelial cells. Accumulation of nano-C 60 (OH) 22-26 in the cells was confirmed spectrophotometrically at 405 nm, and cell viability, cell metabolism and membrane permeability were estimated using trypan blue, MTS and LDH assays, respectively. Fullerol was cytotoxic toward hRPE cells maintained in the dark at concentrations higher than 10 μM. Exposure to an 8.5 J.cm -2 dose of visible light in the presence of > 5 μM fullerol induced TBARS formation and early apoptosis, indicating phototoxic damage in the form of lipid peroxidation. Pretreatment with 10 and 20 μM lutein offered some protection against fullerol photodamage. Using time resolved photophysical techniques, we have now confirmed that fullerol produces singlet oxygen with a quantum yield of Φ = 0.05 in D 2 O and with a range of 0.002-0.139 in various solvents. As our previous studies have shown that fullerol also produces superoxide in the presence of light, retinal phototoxic damage may occur through both type I (free radical) and type II (singlet oxygen) mechanisms. In conclusion, ocular exposure to fullerol, particularly in the presence of sunlight, may lead to retinal damage.

  16. PRMT1 and PRMT4 Regulate Oxidative Stress-Induced Retinal Pigment Epithelial Cell Damage in SIRT1-Dependent and SIRT1-Independent Manners

    Directory of Open Access Journals (Sweden)

    Dong-Il Kim

    2015-01-01

    Full Text Available Oxidative stress-induced retinal pigment epithelial (RPE cell damage is involved in the progression of diabetic retinopathy. Arginine methylation catalyzed by protein arginine methyltransferases (PRMTs has emerged as an important histone modification involved in diverse diseases. Sirtuin (SIRT1 is a protein deacetylase implicated in the onset of metabolic diseases. Therefore, we examined the roles of type I PRMTs and their relationship with SIRT1 in human RPE cells under H2O2-induced oxidative stress. H2O2 treatment increased PRMT1 and PRMT4 expression but decreased SIRT1 expression. Similar to H2O2 treatment, PRMT1 or PRMT4 overexpression increased RPE cell damage. Moreover, the H2O2-induced RPE cell damage was attenuated by PRMT1 or PRMT4 knockdown and SIRT1 overexpression. In this study, we revealed that SIRT1 expression was regulated by PRMT1 but not by PRMT4. Finally, we found that PRMT1 and PRMT4 expression is increased in the RPE layer of streptozotocin-treated rats. Taken together, we demonstrated that oxidative stress induces apoptosis both via PRMT1 in a SIRT1-dependent manner and via PRMT4 in a SIRT1-independent manner. The inhibition of the expression of type I PRMTs, especially PRMT1 and PRMT4, and increased SIRT1 could be therapeutic approaches for diabetic retinopathy.

  17. Molecular regulation of human hematopoietic stem cells

    NARCIS (Netherlands)

    van Galen, P.L.J.

    2014-01-01

    Peter van Galen focuses on understanding the determinants that maintain the stem cell state. Using human hematopoietic stem cells (HSCs) as a model, processes that govern self-renewal and tissue regeneration were investigated. Specifically, a role for microRNAs in balancing the human HSC

  18. Characterization of a spontaneously generated murine retinal pigmented epithelium cell line; a model for in vitro experiments

    International Nuclear Information System (INIS)

    Ranaei Pirmardan, Ehsan; Soheili, Zahra-Soheila; Samiei, Shahram; Ahmadieh, Hamid; Mowla, Seyed Javad; Ezzati, Razie; Naseri, Marzieh

    2016-01-01

    Retinal pigmented epithelium (RPE), the outermost layer of the retina, has a key role in maintaining retinal cells’ functions. Severity of the culture of RPE cells has exerted many limitations to both in vitro and in vivo studies and its therapeutic applications. Therefore, establishment of RPE cell lines with high proliferative potential can considerably improve study of RPE cell biology. Here we report generation of a spontaneously immortalized murine RPE cell line in primary mouse RPE cell culture. Founded colonized cells were picked up and expression of RPE and retinal progenitor cells’ (RPC) markers were studied using immunocytochemistry (ICC). Emerged cells cultured over 35 passages and population doubling times in different serum concentrations were calculated. We also investigated the ability of cells for becoming transfected by calcium-phosphate method and for becoming infected by adeno-associated virus serotype 2 (AAV2) using flow cytometry. Data showed that the cobblestone constituent cells expressed RPE65, cytokeratin and ZO1 and moreover several progenitor markers such as Pax6, Sox2, Nestin and Chx10. It revealed that, despite primary RPE cells, the newly emerged cells were easily transfectable and were highly infectable when compared with HEK293T cells. Our data indicated that the emerged mouse RPE cell line pretended RPC-like phenotype and also simultaneously expressed RPE markers. It would be a promising model for leading studies on RPE and RPC cells and substantially confirmed the great RPE plasticity and its invaluable potential in research studies. - Highlights: • Isolation of a spontaneously generated retinal pigmented epithelium cell line is reported. • The cells express some of the retinal progenitor cell markers in addition to the RPE markers. • The aforesaid cell line is highly transfecable and considerably infectable by AAV2. • These results confirm the great RPE plasticity and its invaluable potential in research studies.

  19. Characterization of a spontaneously generated murine retinal pigmented epithelium cell line; a model for in vitro experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ranaei Pirmardan, Ehsan [Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Soheili, Zahra-Soheila [Department of Molecular Medicine, National Institute of Genetic Engineering and Biotechnology, Tehran (Iran, Islamic Republic of); Samiei, Shahram [Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran (Iran, Islamic Republic of); Ahmadieh, Hamid [Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Mowla, Seyed Javad [Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Ezzati, Razie [Department of Molecular Medicine, National Institute of Genetic Engineering and Biotechnology, Tehran (Iran, Islamic Republic of); Naseri, Marzieh [Department of Molecular Medicine, Faculty of Advanced Technology, Iran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2016-10-01

    Retinal pigmented epithelium (RPE), the outermost layer of the retina, has a key role in maintaining retinal cells’ functions. Severity of the culture of RPE cells has exerted many limitations to both in vitro and in vivo studies and its therapeutic applications. Therefore, establishment of RPE cell lines with high proliferative potential can considerably improve study of RPE cell biology. Here we report generation of a spontaneously immortalized murine RPE cell line in primary mouse RPE cell culture. Founded colonized cells were picked up and expression of RPE and retinal progenitor cells’ (RPC) markers were studied using immunocytochemistry (ICC). Emerged cells cultured over 35 passages and population doubling times in different serum concentrations were calculated. We also investigated the ability of cells for becoming transfected by calcium-phosphate method and for becoming infected by adeno-associated virus serotype 2 (AAV2) using flow cytometry. Data showed that the cobblestone constituent cells expressed RPE65, cytokeratin and ZO1 and moreover several progenitor markers such as Pax6, Sox2, Nestin and Chx10. It revealed that, despite primary RPE cells, the newly emerged cells were easily transfectable and were highly infectable when compared with HEK293T cells. Our data indicated that the emerged mouse RPE cell line pretended RPC-like phenotype and also simultaneously expressed RPE markers. It would be a promising model for leading studies on RPE and RPC cells and substantially confirmed the great RPE plasticity and its invaluable potential in research studies. - Highlights: • Isolation of a spontaneously generated retinal pigmented epithelium cell line is reported. • The cells express some of the retinal progenitor cell markers in addition to the RPE markers. • The aforesaid cell line is highly transfecable and considerably infectable by AAV2. • These results confirm the great RPE plasticity and its invaluable potential in research studies.

  20. Human monoclonal antibodies reactive with human myelomonocytic leukemia cells.

    Science.gov (United States)

    Posner, M R; Santos, D J; Elboim, H S; Tumber, M B; Frackelton, A R

    1989-04-01

    Peripheral blood mononuclear cells from a patient with chronic myelogenous leukemia (CML), in remission, were depleted of CD8-positive T-cells and cultured with Epstein-Barr virus. Four of 20 cultures (20%) secreted human IgG antibodies selectively reactive with the cell surfaces of certain human leukemia cell lines. Three polyclonal, Epstein-Barr virus-transformed, B-cell lines were expanded and fused with the human-mouse myeloma analogue HMMA2.11TG/O. Antibody from secreting clones HL 1.2 (IgG1), HL 2.1 (IgG3), and HL 3.1 (IgG1) have been characterized. All three react with HL-60 (promyelocytic), RWLeu4 (CML promyelocytic), and U937 (monocytic), but not with KG-1 (myeloblastic) or K562 (CML erythroid). There is no reactivity with T-cell lines, Burkitt's cell lines, pre-B-leukemia cell lines, or an undifferentiated CML cell line, BV173. Leukemic cells from two of seven patients with acute myelogenous leukemia and one of five with acute lymphocytic leukemia react with all three antibodies. Normal lymphocytes, monocytes, polymorphonuclear cells, red blood cells, bone marrow cells, and platelets do not react. Samples from patients with other diverse hematopoietic malignancies showed no reactivity. Immunoprecipitations suggest that the reactive antigen(s) is a lactoperoxidase iodinatable series of cell surface proteins with molecular weights of 42,000-54,000 and a noniodinatable protein with a molecular weight of 82,000. Based on these data these human monoclonal antibodies appear to react with myelomonocytic leukemic cells and may detect a leukemia-specific antigen or a highly restricted differentiation antigen.

  1. Human hematopoietic cell culture, transduction, and analyses

    DEFF Research Database (Denmark)

    Bonde, Jesper; Wirthlin, Louisa; Kohn, Donald B

    2008-01-01

    This unit provides methods for introducing genes into human hematopoietic progenitor cells. The Basic Protocol describes isolation of CD34(+) cells, transduction of these cells with a retroviral vector on fibronectin-coated plates, assaying the efficiency of transduction, and establishing long-te...

  2. The lifetime of hypoxic human tumor cells

    International Nuclear Information System (INIS)

    Durand, Ralph E.; Sham, Edward

    1998-01-01

    Purpose: For hypoxic and anoxic cells in solid tumors to be a therapeutic problem, they must live long enough to be therapeutically relevant, or else be rapidly recruited into the proliferating compartment during therapy. We have, therefore, estimated lifetime and recruitment rate of hypoxic human tumor cells in multicell spheroids in vitro, or in xenografted tumors in SCID mice. Materials and Methods: Cell turnover was followed by flow cytometry techniques, using antibodies directed at incorporated halogenated pyrimidines. The disappearance of labeled cells was quantified, and verified to be cell loss rather than label dilution. Repopulation was studied in SiHa tumor xenografts during twice-daily 2.5-Gy radiation exposures. Results: The longevity of hypoxic human tumor cells in spheroids or xenografts exceeded that of rodent cell lines, and cell turnover was slower in xenografts than under static growth as spheroids. Human tumor cells remained viable in the hypoxic regions of xenografts for 4-10 days, compared to 3-5 days in spheroids, and 1-3 days for most rodent cells in spheroids. Repopulation was observed within the first few radiation treatments for the SiHa xenografts and, with accumulated doses of more than 10 Gy, virtually all recovered cells had progressed through at least one S-phase. Conclusion: Our results suggest an important difference in the ability of human vs. rodent tumor cells to withstand hypoxia, and raise questions concerning the increased longevity seen in vivo relative to the steady-state spheroid system

  3. Grafting of ARPE-19 and Schwann cells to the subretinal space in RCS rats.

    Science.gov (United States)

    Wang, Shaomei; Lu, Bin; Wood, Patrick; Lund, Raymond D

    2005-07-01

    To study the distribution of the human retinal pigment epithelium (hRPE) cell line ARPE-19 and human Schwann (hSC) cells grafted to the subretinal space of the Royal College of Surgeon (RCS) rat and the relation of graft cell distribution to photoreceptor rescue. Cell suspensions of both donor types were injected into the subretinal space of 3-week-old dystrophic RCS rats through a transscleral approach, human fibroblast and medium were used as control grafts. All animals were maintained on oral cyclosporine. At 1, 2, 4, 6, 15, 28, and 36 weeks after grafting, animals were killed. Human cell-specific markers were used to localize donor cells. Both donor cell types, as revealed by antibodies survived for a substantial time. Their distribution was very different: hRPE cells formed a large clump early on and, with time, spread along the host RPE in a layer one to two cells deep, whereas hSCs formed many smaller clumps, mainly in the subretinal space. Both cells rescued photoreceptors beyond the area of donor cell distribution. The number of surviving cells declined with time. Both hRPE and hSC grafts can survive and rescue photoreceptors for a substantial time after grafting. The number of both donor cell types declined with time, which could be an immune-related problem and/or due to other factors intrinsic to the host RCS retina. The fact that rescue occurred beyond the area of donor cell distribution suggests that diffusible factors are involved, raising the possibility that the two cell types function in a similar manner to rescue photoreceptors.

  4. Human Pluripotent Stem Cell Differentiation into Functional Epicardial Progenitor Cells

    NARCIS (Netherlands)

    Guadix, Juan Antonio; Orlova, Valeria V.; Giacomelli, Elisa; Bellin, Milena; Ribeiro, Marcelo C.; Mummery, Christine L.; Pérez-Pomares, José M.; Passier, Robert

    2017-01-01

    Human pluripotent stem cells (hPSCs) are widely used to study cardiovascular cell differentiation and function. Here, we induced differentiation of hPSCs (both embryonic and induced) to proepicardial/epicardial progenitor cells that cover the heart during development. Addition of retinoic acid (RA)

  5. Radiation effects on cultured human lymphoid cells

    International Nuclear Information System (INIS)

    Johansson, L.; Nilsson, K.; Carlsson, J.; Larsson, B.; Jakobsson, P.

    1981-01-01

    The cloning efficiency of human normal and malignant lymphoid cells is usually low. Radiation effects in vitro on such cells can therefore not be analysed with conventional cloning. However, this problem can be circumscribed by using the growth extrapolation method. A panel of human leukemia-lymphoma cell-lines representing Epstein-Barr virus carrying lymphoblastoid cells of presumed non-neoplastic derivation and neoplastic T- and B-lymphocytes was used to test the efficiency of this method. The sensitivity to radiation could be determined for all these cell types. The growth extrapolation method gave generally the same result as conventional cloning demonstrated by comparison with one exceptional cell-line with capacity for cloning in agar. The sensitivity varied largely between the different cell types. A common feature was that none of the cell lines had a good capacity to accumulate sublethal radiation injury. (Auth.)

  6. Energy Generation in the Human Body by the Human Cells ...

    African Journals Online (AJOL)

    We adapted the thermodynamics equation for energy generation in a diesel engine in modeling energy generation in human body by the human cells by doing a thorough study on both systems and saw that the process of energy generation is the same in them. We equally saw that the stages involved in energy generation ...

  7. Tuft (caveolated) cells in two human colon carcinoma cell lines.

    Science.gov (United States)

    Barkla, D H; Whitehead, R H; Foster, H; Tutton, P J

    1988-09-01

    The presence of an unusual cell type in two human colon carcinoma cell lines is reported. The cells show the same morphology as "tuft" (caveolated) cells present in normal gastrointestinal epithelium. Tuft cells were seen in cell line LIM 1863 growing in vitro and in human colon carcinoma cell line LIM 2210 growing as subcutaneous solid tumour xenografts in nude mice. Characteristic morphologic features of tuft cells included a wide base, narrow apex and a tuft of long microvilli projecting from the apical surface. The microvilli are attached by a core of long microfilaments passing deep into the apical cytoplasm. Between the microvilli are parallel arrays of vesicles (caveoli) containing flocculent material. Two different but not mutually exclusive explanations for the presence of tuft cells are proposed. The first explanation is that tuft cells came from the resected tumour and have survived by mitotic division during subsequent passages. The second explanation suggests that tuft cells are the progeny of undifferentiated tumour cells. Descriptions of tuft cells in colon carcinomas are uncommon and possible reasons for this are presented. The morphology of tuft cells is consistent with that of a highly differentiated cell specialised for absorption, and these new models provide an opportunity to further investigate the structure and function of tuft cells.

  8. Sensing radiosensitivity of human epidermal stem cells

    International Nuclear Information System (INIS)

    Rachidi, Walid; Harfourche, Ghida; Lemaitre, Gilles; Amiot, Franck; Vaigot, Pierre; Martin, Michele T.

    2007-01-01

    Purpose: Radiosensitivity of stem cells is a matter of debate. For mouse somatic stem cells, both radiosensitive and radioresistant stem cells have been described. By contrast, the response of human stem cells to radiation has been poorly studied. As epidermis is a radiosensitive tissue, we evaluated in the present work the radiosensitivity of cell populations enriched for epithelial stem cells of human epidermis. Methods and materials: The total keratinocyte population was enzymatically isolated from normal human skin. We used flow cytometry and antibodies against cell surface markers to isolate basal cell populations from human foreskin. Cell survival was measured after a dose of 2 Gy with the XTT assay at 72 h after exposure and with a clonogenic assay at 2 weeks. Transcriptome analysis using oligonucleotide microarrays was performed to assess the genomic cell responses to radiation. Results: Cell sorting based on two membrane proteins, α6 integrin and the transferrin receptor CD71, allowed isolation of keratinocyte populations enriched for the two types of cells found in the basal layer of epidermis: stem cells and progenitors. Both the XTT assay and the clonogenic assay showed that the stem cells were radioresistant whereas the progenitors were radiosensitive. We made the hypothesis that upstream DNA damage signalling might be different in the stem cells and used microarray technology to test this hypothesis. The stem cells exhibited a much more reduced gene response to a dose of 2 Gy than the progenitors, as we found that 6% of the spotted genes were regulated in the stem cells and 20% in the progenitors. Using Ingenuity Pathway Analysis software, we found that radiation exposure induced very specific pathways in the stem cells. The most striking responses were the repression of a network of genes involved in apoptosis and the induction of a network of cytokines and growth factors. Conclusion: These results show for the first time that keratinocyte

  9. Human Pluripotent Stem Cell Differentiation into Functional Epicardial Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Juan Antonio Guadix

    2017-12-01

    Full Text Available Summary: Human pluripotent stem cells (hPSCs are widely used to study cardiovascular cell differentiation and function. Here, we induced differentiation of hPSCs (both embryonic and induced to proepicardial/epicardial progenitor cells that cover the heart during development. Addition of retinoic acid (RA and bone morphogenetic protein 4 (BMP4 promoted expression of the mesodermal marker PDGFRα, upregulated characteristic (proepicardial progenitor cell genes, and downregulated transcription of myocardial genes. We confirmed the (proepicardial-like properties of these cells using in vitro co-culture assays and in ovo grafting of hPSC-epicardial cells into chick embryos. Our data show that RA + BMP4-treated hPSCs differentiate into (proepicardial-like cells displaying functional properties (adhesion and spreading over the myocardium of their in vivo counterpart. The results extend evidence that hPSCs are an excellent model to study (proepicardial differentiation into cardiovascular cells in human development and evaluate their potential for cardiac regeneration. : The authors have shown that hPSCs can be instructed in vitro to differentiate into a specific cardiac embryonic progenitor cell population called the proepicardium. Proepicardial cells are required for normal formation of the heart during development and might contribute to the development of cell-based therapies for heart repair. Keywords: human pluripotent stem cells, proepicardium, progenitor cells, cardiovascular, differentiation

  10. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  11. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    International Nuclear Information System (INIS)

    Varga, Nóra; Veréb, Zoltán; Rajnavölgyi, Éva; Német, Katalin; Uher, Ferenc; Sarkadi, Balázs; Apáti, Ágota

    2011-01-01

    Highlights: ► MSC like cells were derived from hESC by a simple and reproducible method. ► Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. ► MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  12. Toxicity of diuron in human cancer cells.

    Science.gov (United States)

    Huovinen, Marjo; Loikkanen, Jarkko; Naarala, Jonne; Vähäkangas, Kirsi

    2015-10-01

    Diuron is a substituted phenylurea used as a herbicide to control broadleaf and grass weeds and as a biocidal antifouling agent. Diuron is carcinogenic in rat urinary bladder and toxic to the reproductive system of oysters, sea urchins and lizards. The few studies carried out in human cells do not include the genotoxicity of diuron. We have investigated the toxicity of diuron in human breast adenocarcinoma (MCF-7) and human placental choriocarcinoma (BeWo) cells. The production of reactive oxygen species (ROS) was statistically significantly increased in both cell lines but only at the highest 200 μM concentration. Diuron clearly reduced the viability of BeWo, but not MCF-7 cells. The relative cell number was decreased in both cell lines indicative of inhibition of cell proliferation. In the Comet assay, diuron increased DNA fragmentation in MCF-7 but not in BeWo cells. The expressions of p53 protein, a marker for cell stress, and p21 protein, a transcriptional target of p53, were increased, but only in MCF-7 cells. In conclusion, our results suggest that diuron is cytotoxic and potentially genotoxic in a tissue-specific manner and that ROS play a role in its toxicity. Thus, exposure to diuron may exert harmful effects on fetal development and damage human health. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Regulatory T Cells in Human Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Dong-Jun Peng

    2012-01-01

    Full Text Available Multiple layers of suppressive components including regulatory T (TReg cells, suppressive antigen-presenting cells, and inhibitory cytokines form suppressive networks in the ovarian cancer microenvironment. It has been demonstrated that as a major suppressive element, TReg cells infiltrate tumor, interact with several types of immune cells, and mediate immune suppression through different molecular and cellular mechanisms. In this paper, we focus on human ovarian cancer and will discuss the nature of TReg cells including their subsets, trafficking, expansion, and function. We will briefly review the development of manipulation of TReg cells in preclinical and clinical settings.

  14. Genome Editing in Human Pluripotent Stem Cells.

    Science.gov (United States)

    Carlson-Stevermer, Jared; Saha, Krishanu

    2017-01-01

    Genome editing in human pluripotent stem cells (hPSCs) enables the generation of reporter lines and knockout cell lines. Zinc finger nucleases, transcription activator-like effector nucleases (TALENs), and CRISPR/Cas9 technology have recently increased the efficiency of proper gene editing by creating double strand breaks (DSB) at defined sequences in the human genome. These systems typically use plasmids to transiently transcribe nucleases within the cell. Here, we describe the process for preparing hPSCs for transient expression of nucleases via electroporation and subsequent analysis to create genetically modified stem cell lines.

  15. Modeling human infertility with pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Di Chen

    2017-05-01

    Full Text Available Human fertility is dependent upon the correct establishment and differentiation of the germline. This is because no other cell type in the body is capable of passing a genome and epigenome from parent to child. Terminally differentiated germline cells in the adult testis and ovary are called gametes. However, the initial specification of germline cells occurs in the embryo around the time of gastrulation. Most of our knowledge regarding the cell and molecular events that govern human germline specification involves extrapolating scientific principles from model organisms, most notably the mouse. However, recent work using next generation sequencing, gene editing and differentiation of germline cells from pluripotent stem cells has revealed that the core molecular mechanisms that regulate human germline development are different from rodents. Here, we will discuss the major molecular pathways required for human germline differentiation and how pluripotent stem cells have revolutionized our ability to study the earliest steps in human embryonic lineage specification in order to understand human fertility.

  16. Performance measurement of a new concept reciprocating piston expander (RPE using a newly developed small-scale dynamometer unit

    Directory of Open Access Journals (Sweden)

    Mohamad MNA

    2017-01-01

    Full Text Available This paper presents the progress of a small-scale dynamometer prototype development for performance measurement of a reciprocating piston expander (RPE. Since the available dynamometer systems in the market are limited to specific applications that require for the customization, their price normally very expensive. Since the current study on the RPE required a dynamometer unit, therefore, a new and cheaper dynamometer prototype that was suitable for RPE application has been developed. Using air as RPE working fluid, a case study has been carried out to measure its performance at different inlet fluid conditions, i.e., within 20°C–140°C and 3–5 bars. The results observed that the performance of RPE was proportionally increased to the increased of inlet fluid pressure and temperature. The maximum brake power produced was 27 Watt when the RPE operated at 140°C, 5 bars and the speed of 820 rpm. It also revealed that the changes in the pressure of inlet fluid can give significant change on the performance of the RPE due to its direct relation to the RPE actual rotating force. Although the RPE and dynamometer seem good being adapted to each other, both of them require some improvements to ensure both systems well operated and reliable.

  17. Retinal pigment epithelial cell multinucleation in the aging eye - a mechanism to repair damage and maintain homoeostasis.

    Science.gov (United States)

    Chen, Mei; Rajapakse, Dinusha; Fraczek, Monika; Luo, Chang; Forrester, John V; Xu, Heping

    2016-06-01

    Retinal pigment epithelial (RPE) cells are central to retinal health and homoeostasis. Dysfunction or death of RPE cells underlies many age-related retinal degenerative disorders particularly age-related macular degeneration. During aging RPE cells decline in number, suggesting an age-dependent cell loss. RPE cells are considered to be postmitotic, and how they repair damage during aging remains poorly defined. We show that RPE cells increase in size and become multinucleate during aging in C57BL/6J mice. Multinucleation appeared not to be due to cell fusion, but to incomplete cell division, that is failure of cytokinesis. Interestingly, the phagocytic activity of multinucleate RPE cells was not different from that of mononuclear RPE cells. Furthermore, exposure of RPE cells in vitro to photoreceptor outer segment (POS), particularly oxidized POS, dose-dependently promoted multinucleation and suppressed cell proliferation. Both failure of cytokinesis and suppression of proliferation required contact with POS. Exposure to POS also induced reactive oxygen species and DNA oxidation in RPE cells. We propose that RPE cells have the potential to proliferate in vivo and to repair defects in the monolayer. We further propose that the conventionally accepted 'postmitotic' status of RPE cells is due to a modified form of contact inhibition mediated by POS and that RPE cells are released from this state when contact with POS is lost. This is seen in long-standing rhegmatogenous retinal detachment as overtly proliferating RPE cells (proliferative vitreoretinopathy) and more subtly as multinucleation during normal aging. Age-related oxidative stress may promote failure of cytokinesis and multinucleation in RPE cells. © 2016 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  18. Plasma membrane proteomics of human embryonic stem cells and human embryonal carcinoma cells.

    NARCIS (Netherlands)

    Dormeyer, W.; van Hoof, D.; Braam, S.R.; Heck, A.J.R.; Mummery, C.L.; Krijgsveld, J.

    2008-01-01

    Human embryonic stem cells (hESCs) are of immense interest in regenerative medicine as they can self-renew indefinitely and can give rise to any adult cell type. Human embryonal carcinoma cells (hECCs) are the malignant counterparts of hESCs found in testis tumors. hESCs that have acquired

  19. Guidelines for human embryonic stem cell research

    National Research Council Canada - National Science Library

    Committee on Guidelines for Human Embryonic Stem Cell Research, National Research Council

    2005-01-01

    Since 1998, the volume of research being conducted using human embryonic stem (hES) cells has expanded primarily using private funds because of restrictions on the use of federal funds for such research...

  20. Satellite cells in human skeletal muscle plasticity

    Directory of Open Access Journals (Sweden)

    Tim eSnijders

    2015-10-01

    Full Text Available Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodelling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to humans under physiological conditions. Findings from in vivo human studies suggest that satellite cells play a key role in skeletal muscle fiber repair/remodelling in response to exercise. Mounting evidence indicates that aging has a profound impact on the regulation of satellite cells in human skeletal muscle. Yet, the precise role of satellite cells in the development of muscle fiber atrophy with age remains unresolved. This review seeks to integrate recent results from in vivo human studies on satellite cell function in muscle fiber repair/remodelling in the wider context of satellite cell biology whose literature is largely based on animal and cell models.

  1. Validity and reliability of the session-RPE method for quantifying training load in karate athletes.

    Science.gov (United States)

    Tabben, M; Tourny, C; Haddad, M; Chaabane, H; Chamari, K; Coquart, J B

    2015-04-24

    To test the construct validity and reliability of the session rating of perceived exertion (sRPE) method by examining the relationship between RPE and physiological parameters (heart rate: HR and blood lactate concentration: [La --] ) and the correlations between sRPE and two HR--based methods for quantifying internal training load (Banister's method and Edwards's method) during karate training camp. Eighteen elite karate athletes: ten men (age: 24.2 ± 2.3 y, body mass: 71.2 ± 9.0 kg, body fat: 8.2 ± 1.3% and height: 178 ± 7 cm) and eight women (age: 22.6 ± 1.2 y, body mass: 59.8 ± 8.4 kg, body fat: 20.2 ± 4.4%, height: 169 ± 4 cm) were included in the study. During training camp, subjects participated in eight karate--training sessions including three training modes (4 tactical--technical, 2 technical--development, and 2 randori training), during which RPE, HR, and [La -- ] were recorded. Significant correlations were found between RPE and physiological parameters (percentage of maximal HR: r = 0.75, 95% CI = 0.64--0.86; [La --] : r = 0.62, 95% CI = 0.49--0.75; P training load ( r = 0.65--0.95; P reliability of the same intensity across training sessions (Cronbach's α = 0.81, 95% CI = 0.61--0.92). This study demonstrates that the sRPE method is valid for quantifying internal training load and intensity in karate.

  2. Human Ocular Epithelial Cells Endogenously Expressing SOX2 and OCT4 Yield High Efficiency of Pluripotency Reprogramming.

    Directory of Open Access Journals (Sweden)

    Ming-Wai Poon

    Full Text Available A variety of pluripotency reprogramming frequencies from different somatic cells has been observed, indicating cell origin is a critical contributor for efficiency of pluripotency reprogramming. Identifying the cell sources for efficient induced pluripotent stem cells (iPSCs generation, and defining its advantages or disadvantages on reprogramming, is therefore important. Human ocular tissue-derived conjunctival epithelial cells (OECs exhibited endogenous expression of reprogramming factors OCT4A (the specific OCT 4 isoform on pluripotency reprogramming and SOX2. We therefore determined whether OECs could be used for high efficiency of iPSCs generation. We compared the endogenous expression levels of four pluripotency factors and the pluripotency reprograming efficiency of human OECs with that of ocular stromal cells (OSCs. Real-time PCR, microarray analysis, Western blotting and immunostaining assays were employed to compare OECiPSCs with OSCiPSCs on molecular bases of reprogramming efficiency and preferred lineage-differentiation potential. Using the traditional KMOS (KLF4, C-MYC, OCT4 and SOX2 reprogramming protocol, we confirmed that OECs, endogenously expressing reprogramming factors OCT4A and SOX2, yield very high efficiency of iPSCs generation (~1.5%. Furthermore, higher efficiency of retinal pigmented epithelial differentiation (RPE cells was observed in OECiPSCs compared to OSCiPSCs or skin fibroblast iMR90iPSCs. The findings in this study suggest that conjunctival-derived epithelial (OECs cells can be easier converted to iPSCs than conjunctival-derived stromal cells (OSCs. This cell type may also have advantages in retinal pigmented epithelial differentiation.

  3. Human Ocular Epithelial Cells Endogenously Expressing SOX2 and OCT4 Yield High Efficiency of Pluripotency Reprogramming.

    Science.gov (United States)

    Poon, Ming-Wai; He, Jia; Fang, Xiaowei; Zhang, Zhao; Wang, Weixin; Wang, Junwen; Qiu, Fangfang; Tse, Hung-Fat; Li, Wei; Liu, Zuguo; Lian, Qizhou

    2015-01-01

    A variety of pluripotency reprogramming frequencies from different somatic cells has been observed, indicating cell origin is a critical contributor for efficiency of pluripotency reprogramming. Identifying the cell sources for efficient induced pluripotent stem cells (iPSCs) generation, and defining its advantages or disadvantages on reprogramming, is therefore important. Human ocular tissue-derived conjunctival epithelial cells (OECs) exhibited endogenous expression of reprogramming factors OCT4A (the specific OCT 4 isoform on pluripotency reprogramming) and SOX2. We therefore determined whether OECs could be used for high efficiency of iPSCs generation. We compared the endogenous expression levels of four pluripotency factors and the pluripotency reprograming efficiency of human OECs with that of ocular stromal cells (OSCs). Real-time PCR, microarray analysis, Western blotting and immunostaining assays were employed to compare OECiPSCs with OSCiPSCs on molecular bases of reprogramming efficiency and preferred lineage-differentiation potential. Using the traditional KMOS (KLF4, C-MYC, OCT4 and SOX2) reprogramming protocol, we confirmed that OECs, endogenously expressing reprogramming factors OCT4A and SOX2, yield very high efficiency of iPSCs generation (~1.5%). Furthermore, higher efficiency of retinal pigmented epithelial differentiation (RPE cells) was observed in OECiPSCs compared to OSCiPSCs or skin fibroblast iMR90iPSCs. The findings in this study suggest that conjunctival-derived epithelial (OECs) cells can be easier converted to iPSCs than conjunctival-derived stromal cells (OSCs). This cell type may also have advantages in retinal pigmented epithelial differentiation.

  4. Human stem cells for craniomaxillofacial reconstruction.

    Science.gov (United States)

    Jalali, Morteza; Kirkpatrick, William Niall Alexander; Cameron, Malcolm Gregor; Pauklin, Siim; Vallier, Ludovic

    2014-07-01

    Human stem cell research represents an exceptional opportunity for regenerative medicine and the surgical reconstruction of the craniomaxillofacial complex. The correct architecture and function of the vastly diverse tissues of this important anatomical region are critical for life supportive processes, the delivery of senses, social interaction, and aesthetics. Craniomaxillofacial tissue loss is commonly associated with inflammatory responses of the surrounding tissue, significant scarring, disfigurement, and psychological sequelae as an inevitable consequence. The in vitro production of fully functional cells for skin, muscle, cartilage, bone, and neurovascular tissue formation from human stem cells, may one day provide novel materials for the reconstructive surgeon operating on patients with both hard and soft tissue deficit due to cancer, congenital disease, or trauma. However, the clinical translation of human stem cell technology, including the application of human pluripotent stem cells (hPSCs) in novel regenerative therapies, faces several hurdles that must be solved to permit safe and effective use in patients. The basic biology of hPSCs remains to be fully elucidated and concerns of tumorigenicity need to be addressed, prior to the development of cell transplantation treatments. Furthermore, functional comparison of in vitro generated tissue to their in vivo counterparts will be necessary for confirmation of maturity and suitability for application in reconstructive surgery. Here, we provide an overview of human stem cells in disease modeling, drug screening, and therapeutics, while also discussing the application of regenerative medicine for craniomaxillofacial tissue deficit and surgical reconstruction.

  5. Human neutrophils facilitate tumor cell transendothelial migration.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

  6. HLA engineering of human pluripotent stem cells.

    Science.gov (United States)

    Riolobos, Laura; Hirata, Roli K; Turtle, Cameron J; Wang, Pei-Rong; Gornalusse, German G; Zavajlevski, Maja; Riddell, Stanley R; Russell, David W

    2013-06-01

    The clinical use of human pluripotent stem cells and their derivatives is limited by the rejection of transplanted cells due to differences in their human leukocyte antigen (HLA) genes. This has led to the proposed use of histocompatible, patient-specific stem cells; however, the preparation of many different stem cell lines for clinical use is a daunting task. Here, we develop two distinct genetic engineering approaches that address this problem. First, we use a combination of gene targeting and mitotic recombination to derive HLA-homozygous embryonic stem cell (ESC) subclones from an HLA-heterozygous parental line. A small bank of HLA-homozygous stem cells with common haplotypes would match a significant proportion of the population. Second, we derive HLA class I-negative cells by targeted disruption of both alleles of the Beta-2 Microglobulin (B2M) gene in ESCs. Mixed leukocyte reactions and peptide-specific HLA-restricted CD8(+) T cell responses were reduced in class I-negative cells that had undergone differentiation in embryoid bodies. These B2M(-/-) ESCs could act as universal donor cells in applications where the transplanted cells do not express HLA class II genes. Both approaches used adeno-associated virus (AAV) vectors for efficient gene targeting in the absence of potentially genotoxic nucleases, and produced pluripotent, transgene-free cell lines.

  7. HLA Engineering of Human Pluripotent Stem Cells

    Science.gov (United States)

    Riolobos, Laura; Hirata, Roli K; Turtle, Cameron J; Wang, Pei-Rong; Gornalusse, German G; Zavajlevski, Maja; Riddell, Stanley R; Russell, David W

    2013-01-01

    The clinical use of human pluripotent stem cells and their derivatives is limited by the rejection of transplanted cells due to differences in their human leukocyte antigen (HLA) genes. This has led to the proposed use of histocompatible, patient-specific stem cells; however, the preparation of many different stem cell lines for clinical use is a daunting task. Here, we develop two distinct genetic engineering approaches that address this problem. First, we use a combination of gene targeting and mitotic recombination to derive HLA-homozygous embryonic stem cell (ESC) subclones from an HLA-heterozygous parental line. A small bank of HLA-homozygous stem cells with common haplotypes would match a significant proportion of the population. Second, we derive HLA class I–negative cells by targeted disruption of both alleles of the Beta-2 Microglobulin (B2M) gene in ESCs. Mixed leukocyte reactions and peptide-specific HLA-restricted CD8+ T cell responses were reduced in class I–negative cells that had undergone differentiation in embryoid bodies. These B2M−/− ESCs could act as universal donor cells in applications where the transplanted cells do not express HLA class II genes. Both approaches used adeno-associated virus (AAV) vectors for efficient gene targeting in the absence of potentially genotoxic nucleases, and produced pluripotent, transgene-free cell lines. PMID:23629003

  8. Influence of ultraviolet A radiation on osmolytes transport in human retinal pigment epithelial cells

    Directory of Open Access Journals (Sweden)

    Da-Yang Wu

    2014-04-01

    Full Text Available AIM: To demonstrate that ultraviolet A(UVAinduces osmolytes accumulation in retinal pigment epithelial(RPEcells.METHODS: Under different experimental conditions such as UVA exposure, hyperosmotic stress condition and hypoosmotic stress condition, RPE cells were cultured for different time periods. The betaine /γ-amino- n-butyric acid(GABAtransporter, the sodium-dependent myoinositol transporter and the taurine transporter(TAUTmRNA were measured by quantitative PCR. The radioactive labeled osmolytes were measured to evaluate the level of osmolytes transportation. RESULTS: This study demonstrated that RPE expressed mRNA specific for the betaine/GABA transporter, for the sodium-dependent myoinositol transporter and for the TAUT. In comparison to norm osmotic(300mosmol/Lcontrols, a 3-5-fold induction of mRNA expression for the betaine/GABA transporter, the sodium-dependent myoinositol transporter and the TAUT was observed within 6-24h after hyperosmotic exposure(400mosmol/L. Expression of osmolyte transporters was associated with an increased uptake of radioactive labeled osmolytes. Conversely, hypoosmotic(200mosmol/Lstimulation induced significant efflux of these osmolytes. UVA significantly stimulated osmolyte uptake. Increased osmolyte uptake was associated with upregulation of mRNA steady-state levels for osmolyte transporters in irradiated cells.CONCLUSION: UVA induces osmolyte uptake in RPE. It is similar reaction to hyperosmotic stress. This suggests that osmolyte uptake response by UVA may be important to maintain homeostasis.

  9. DNA fork displacement rates in human cells

    International Nuclear Information System (INIS)

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

    1981-01-01

    DNA fork displacement rates were measured in 20 human cell lines by a bromodeoxyuridine-313 nm photolysis technique. Cell lines included representatives of normal diploid, Fanconi's anemia, ataxia telangiectasia, xeroderma pigmentosum, trisomy-21 and several transformed lines. The average value for all the cell lines was 0.53 +- 0.08 μm/min. The average value for individual cell lines, however, displayed a 30% variation. Less than 10% of variation in the fork displacement rate appears to be due to the experimental technique; the remainder is probably due to true variation among the cell types and to culture conditions. (Auth.)

  10. DNA fork displacement rates in human cells

    Energy Technology Data Exchange (ETDEWEB)

    Kapp, L.N.; Painter, R.B. (California Univ., San Francisco (USA). Lab. of Radiobiology)

    1981-11-27

    DNA fork displacement rates were measured in 20 human cell lines by a bromodeoxyuridine-313 nm photolysis technique. Cell lines included representatives of normal diploid, Fanconi's anemia, ataxia telangiectasia, xeroderma pigmentosum, trisomy-21 and several transformed lines. The average value for all the cell lines was 0.53 +- 0.08 ..mu..m/min. The average value for individual cell lines, however, displayed a 30% variation. Less than 10% of variation in the fork displacement rate appears to be due to the experimental technique; the remainder is probably due to true variation among the cell types and to culture conditions.

  11. Signaling hierarchy regulating human endothelial cell development

    Science.gov (United States)

    Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these stud...

  12. The biology of human innate lymphoid cells

    NARCIS (Netherlands)

    Bernink, J.H.J.

    2016-01-01

    In this thesis I performed studies to investigate the contribution of human innate lymphoid cells (ILCs) in maintaining the mucosal homeostasis, initiating and/or propagating inflammatory responses, but also - when not properly regulated - how these cells contribute to immunopathology. First I

  13. 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

  14. The effect of culture density and proliferation rate on the expression of ouabain-sensitive Na/K ATPase pumps in cultured human retinal pigment epithelium

    International Nuclear Information System (INIS)

    Burke, J.M.; Jaffe, G.J.; Brzeski, C.M.

    1991-01-01

    The number and activity of ouabain-sensitive Na/K ATPase pumps expressed by many cell types in vitro, including human retinal pigment epithelial cells (RPE), have been shown to decline with increasing culture density. Cell proliferation also declined as cultures became dense so it was unclear if pump number was modulated by cell proliferation or culture confluency. By exposing RPE cultures to various feeding regimens, using culture medium containing or lacking serum, it was possible to produce RPE cultures with a range of culture densities and growth rates. These were analyzed for proliferative activity by quantifying [ 3 H]thymidine incorporation and for Na/K ATPase pump number by measuring specific [ 3 H]ouabain binding. The results suggest that pump number is modulated by culture density and, further, that the density-dependent regulation of pump number requires serum. Although density-dependent modulation of culture growth is also serum requiring, cell proliferation and pump number did not appear to be related; cultures of similar density which differed significantly in growth rate had similar numbers of pumps. The view that elevated numbers of pumps were not necessarily found in proliferating cells was further supported by qualitative examination of radioautographs of cells dually labeled with [ 3 H]thymidine and [ 3 H]ouabain. Cycling cells which had [ 3 H]thymidine-labeled nuclei did not have notably higher labeling with [ 3 H]ouabain. However, [ 3 H]ouabain labeling, as an indicator of pump site number and distribution, did vary among cells in an RPE population and also within individual cells. This latter observation suggests that unpolarized RPE cells in sparse cultures may have regionally different requirements for ionic regulation

  15. The effect of culture density and proliferation rate on the expression of ouabain-sensitive Na/K ATPase pumps in cultured human retinal pigment epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Burke, J.M.; Jaffe, G.J.; Brzeski, C.M. (Medical College of Wisconsin, Milwaukee (USA))

    1991-06-01

    The number and activity of ouabain-sensitive Na/K ATPase pumps expressed by many cell types in vitro, including human retinal pigment epithelial cells (RPE), have been shown to decline with increasing culture density. Cell proliferation also declined as cultures became dense so it was unclear if pump number was modulated by cell proliferation or culture confluency. By exposing RPE cultures to various feeding regimens, using culture medium containing or lacking serum, it was possible to produce RPE cultures with a range of culture densities and growth rates. These were analyzed for proliferative activity by quantifying ({sup 3}H)thymidine incorporation and for Na/K ATPase pump number by measuring specific ({sup 3}H)ouabain binding. The results suggest that pump number is modulated by culture density and, further, that the density-dependent regulation of pump number requires serum. Although density-dependent modulation of culture growth is also serum requiring, cell proliferation and pump number did not appear to be related; cultures of similar density which differed significantly in growth rate had similar numbers of pumps. The view that elevated numbers of pumps were not necessarily found in proliferating cells was further supported by qualitative examination of radioautographs of cells dually labeled with ({sup 3}H)thymidine and ({sup 3}H)ouabain. Cycling cells which had ({sup 3}H)thymidine-labeled nuclei did not have notably higher labeling with ({sup 3}H)ouabain. However, ({sup 3}H)ouabain labeling, as an indicator of pump site number and distribution, did vary among cells in an RPE population and also within individual cells. This latter observation suggests that unpolarized RPE cells in sparse cultures may have regionally different requirements for ionic regulation.

  16. Haematopoietic stem and progenitor cells from human pluripotent stem cells

    Science.gov (United States)

    Sugimura, Ryohichi; Jha, Deepak Kumar; Han, Areum; Soria-Valles, Clara; da Rocha, Edroaldo Lummertz; Lu, Yi-Fen; Goettel, Jeremy A.; Serrao, Erik; Rowe, R. Grant; Malleshaiah, Mohan; Wong, Irene; Sousa, Patricia; Zhu, Ted N.; Ditadi, Andrea; Keller, Gordon; Engelman, Alan N.; Snapper, Scott B.; Doulatov, Sergei; Daley, George Q.

    2018-01-01

    A variety of tissue lineages can be differentiated from pluripotent stem cells by mimicking embryonic development through stepwise exposure to morphogens, or by conversion of one differentiated cell type into another by enforced expression of master transcription factors. Here, to yield functional human haematopoietic stem cells, we perform morphogen-directed differentiation of human pluripotent stem cells into haemogenic endothelium followed by screening of 26 candidate haematopoietic stem-cell-specifying transcription factors for their capacity to promote multi-lineage haematopoietic engraftment in mouse hosts. We recover seven transcription factors (ERG, HOXA5, HOXA9, HOXA10, LCOR, RUNX1 and SPI1) that are sufficient to convert haemogenic endothelium into haematopoietic stem and progenitor cells that engraft myeloid, B and T cells in primary and secondary mouse recipients. Our combined approach of morphogen-driven differentiation and transcription-factor-mediated cell fate conversion produces haematopoietic stem and progenitor cells from pluripotent stem cells and holds promise for modelling haematopoietic disease in humanized mice and for therapeutic strategies in genetic blood disorders. PMID:28514439

  17. Intrinsic radiation resistance in human chondrosarcoma cells

    International Nuclear Information System (INIS)

    Moussavi-Harami, Farid; Mollano, Anthony; Martin, James A.; Ayoob, Andrew; Domann, Frederick E.; Gitelis, Steven; Buckwalter, Joseph A.

    2006-01-01

    Human chondrosarcomas rarely respond to radiation treatment, limiting the options for eradication of these tumors. The basis of radiation resistance in chondrosarcomas remains obscure. In normal cells radiation induces DNA damage that leads to growth arrest or death. However, cells that lack cell cycle control mechanisms needed for these responses show intrinsic radiation resistance. In previous work, we identified immortalized human chondrosarcoma cell lines that lacked p16 ink4a , one of the major tumor suppressor proteins that regulate the cell cycle. We hypothesized that the absence of p16 ink4a contributes to the intrinsic radiation resistance of chondrosarcomas and that restoring p16 ink4a expression would increase their radiation sensitivity. To test this we determined the effects of ectopic p16 ink4a expression on chondrosarcoma cell resistance to low-dose γ-irradiation (1-5 Gy). p16 ink4a expression significantly increased radiation sensitivity in clonogenic assays. Apoptosis did not increase significantly with radiation and was unaffected by p16 ink4a transduction of chondrosarcoma cells, indicating that mitotic catastrophe, rather than programmed cell death, was the predominant radiation effect. These results support the hypothesis that p16 ink4a plays a role in the radiation resistance of chondrosarcoma cell lines and suggests that restoring p16 expression will improve the radiation sensitivity of human chondrosarcomas

  18. DNA repair in human bronchial epithelial cells

    International Nuclear Information System (INIS)

    Fornace, A.J. Jr.; Lechner, J.F.; Grafstrom, R.C.; Harris, C.C.

    1982-01-01

    The purpose of this investigation was to compare the response of human cell types (bronchial epithelial cells and fibroblasts and skin fibroblasts) to various DNA damaging agents. Repair of DNA single strand breaks (SSB) induced by 5 krads of X-ray was similar for all cell types; approximately 90% of the DNA SSB were rejoined within one hour. During excision repair of DNA damage from u.v.-radiation, the frequencies of DNA SSB as estimated by the alkaline elution technique, were similar in all cell types. Repair replication as measured by BND cellulose chromatography was also similar in epithelial and fibroblastic cells after u.v.-irradiation. Similar levels of SSB were also observed in epithelial and fibroblastic cells after exposure to chemical carcinogens: 7,12-dimethylbenz[a]anthracene; benzo[a]pyrene diol epoxide (BPDE); or N-methyl-N-nitro-N-nitrosoguanidine. Significant repair replication of BPDE-induced DNA damage was detected in both bronchial epithelial and fibroblastic cells, although the level in fibroblasts was approximately 40% of that in epithelial cells. The pulmonary carcinogen asbestos did not damage DNA. DNA-protein crosslinks induced by formaldehyde were rapidly removed in bronchial cells. Further, epithelial and fibroblastic cells, which were incubated with formaldehyde and the polymerase inhibitor combination of cytosine arabinoside and hydroxyurea, accumulated DNA SSB at approximately equal frequencies. These results should provide a useful background for further investigations of the response of human bronchial cells to various DNA damaging agents

  19. Interaction of Staphylococci with Human B cells.

    Directory of Open Access Journals (Sweden)

    Tyler K Nygaard

    Full Text Available Staphylococcus aureus is a leading cause of human infections worldwide. The pathogen produces numerous molecules that can interfere with recognition and binding by host innate immune cells, an initial step required for the ingestion and subsequent destruction of microbes by phagocytes. To better understand the interaction of this pathogen with human immune cells, we compared the association of S. aureus and S. epidermidis with leukocytes in human blood. We found that a significantly greater proportion of B cells associated with S. epidermidis relative to S. aureus. Complement components and complement receptors were important for the binding of B cells with S. epidermidis. Experiments using staphylococci inactivated by ultraviolet radiation and S. aureus isogenic deletion mutants indicated that S. aureus secretes molecules regulated by the SaeR/S two-component system that interfere with the ability of human B cells to bind this bacterium. We hypothesize that the relative inability of B cells to bind S. aureus contributes to the microbe's success as a human pathogen.

  20. Transport of thiol-conjugates of inorganic mercury in human retinal pigment epithelial cells

    International Nuclear Information System (INIS)

    Bridges, Christy C.; Battle, Jamie R.; Zalups, Rudolfs K.

    2007-01-01

    Inorganic mercury (Hg 2+ ) is a prevalent environmental contaminant to which exposure to can damage rod photoreceptor cells and compromise scotopic vision. The retinal pigment epithelium (RPE) likely plays a role in the ocular toxicity associated with Hg 2+ exposure in that it mediates transport of substances to the photoreceptor cells. In order for Hg 2+ to access photoreceptor cells, it must first be taken up by the RPE, possibly by mechanisms involving transporters of essential nutrients. In other epithelia, Hg 2+ , when conjugated to cysteine (Cys) or homocysteine (Hcy), gains access to the intracellular compartment of the target cells via amino acid and organic anion transporters. Accordingly, the purpose of the current study was to test the hypothesis that Cys and Hcy S-conjugates of Hg 2+ utilize amino acid transporters to gain access into RPE cells. Time- and temperature-dependence, saturation kinetics, and substrate-specificity of the transport of Hg 2+ , was assessed in ARPE-19 cells exposed to the following S-conjugates of Hg 2+ : Cys (Cys-S-Hg-S-Cys), Hcy (Hcy-S-Hg-S-Hcy), N-acetylcysteine (NAC-S-Hg-S-NAC) or glutathione (GSH-S-Hg-S-GSH). We discovered that only Cys-S-Hg-S-Cys and Hcy-S-Hg-S-Hcy were taken up by these cells. This transport was Na + -dependent and was inhibited by neutral and cationic amino acids. RT-PCR analyses identified systems B 0,+ and ASC in ARPE-19 cells. Overall, our data suggest that Cys-S-Hg-S-Cys and Hcy-S-Hg-S-Hcy are taken up into ARPE-19 cells by Na-dependent amino acid transporters, possibly systems B 0,+ and ASC. These amino acid transporters may play a role in the retinal toxicity observed following exposure to mercury

  1. TRANSPORT OF THIOL-CONJUGATES OF INORGANIC MERCURY IN HUMAN RETINAL PIGMENT EPITHELIAL CELLS

    Science.gov (United States)

    Bridges, Christy C.; Battle, Jamie R.; Zalups, Rudolfs K.

    2007-01-01

    Inorganic mercury (Hg2+) is a prevalent environmental contaminant to which exposure to can damage rod photoreceptor cells and compromise scotopic vision. The retinal pigment epithelium (RPE) likely plays a role in the ocular toxicity associated with Hg2+ exposure in that it mediates transport of substances to the photoreceptor cells. In order for Hg2+ to access photoreceptor cells, it must be first be taken up by the RPE, possibly by mechanisms involving transporters of essential nutrients. In other epithelia, Hg2+, when conjugated to cysteine (Cys) or homocysteine (Hcy), gains access to the intracellular compartment of the target cells via amino acid and organic anion transporters. Accordingly, the purpose of the current study was to test the hypothesis that Cys and Hcy S-conjugates of Hg2+ utilize amino acid transporters to gain access into RPE cells. Time- and temperature-dependence, saturation kinetics, and substrate-specificity of the transport of Hg2+, was assessed in ARPE-19 cells exposed to the following S-conjugates of Hg2+: Cys (Cys-S-Hg-S-Cys), Hcy (Hcy-S-Hg-S-Hcy), N-acetylcysteine (NAC-S-Hg-S-NAC) or glutathione (GSH-S-Hg-S-GSH). We discovered that only Cys-S-Hg-S-Cys and Hcy-S-Hg-S-Hcy were taken up by these cells. This transport was Na+-dependent and was inhibited by neutral and cationic amino acids. RT-PCR analyses identified systems B0,+ and ASC in ARPE-19 cells. Overall, our data suggest that Cys-S-Hg-S-Cys and Hcy-S-Hg-S-Hcy are taken up into ARPE-19 cells by Na-dependent amino acid transporters, possibly systems B0,+ and ASC. These amino acid transporters may play a role in the retinal toxicity observed following exposure to mercury. PMID:17467761

  2. The Expansion of RPE Atrophy after the Inverted ILM Flap Technique for a Chronic Large Macular Hole

    Directory of Open Access Journals (Sweden)

    Hisanori Imai

    2014-03-01

    Full Text Available Purpose: To report a case of the expansion of submacular retinal pigment epithelium (RPE atrophy after using the inverted internal limiting membrane (ILM flap technique for a persisting, large, stage IV macular hole (MH. Case Report: A 79-year-old woman presented with a chronic large MH that remained open despite pars plana vitrectomy (PPV. The surgery was performed twice for the MH closure 14 years earlier. ILM peeling was not performed during the previous surgeries. The best-corrected visual acuity (BCVA with the Landolt ring chart was 0.08 at her visit. The minimum MH diameter was 1,240 μm. Inverted ILM flap technique with 20% SF6 gas tamponade was performed for the MH closure. For the inverted ILM flap technique, 25-gauge PPV and ILM staining with indocyanine green were used. The ILM was peeled off for 2 disc diameters around the MH, but the ILM was not removed completely. The ILM was then inverted and covered the MH. Results: One month after surgery, the MH was closed, accompanied by glial cell proliferation spreading from the inverted ILM flap (as reported before. On the other hand, the area of the submacular RPE atrophy, which was already observed 1 week after surgery, gradually increased in size. BCVA improved to 0.3 six months after the surgery. Conclusions: The inverted ILM flap technique may be promising even for persisting large MH which were not closed in previous surgeries, but long-term observation is needed because the detailed behavior of the inverted ILM and the Müller cells after surgery is not yet known.

  3. Microphthalmia-associated transcription factor as the molecular target of cadmium toxicity in human melanocytes

    International Nuclear Information System (INIS)

    Chantarawong, Wipa; Takeda, Kazuhisa; Sangartit, Weerapon; Yoshizawa, Miki; Pradermwong, Kantimanee; Shibahara, Shigeki

    2014-01-01

    Highlights: • In human melanocytes, cadmium decreases the expression of MITF-M and tyrosinase and their mRNAs. • In human melanoma cells, cadmium decreases the expression of MITF-M protein and tyrosinase mRNA. • Expression of MITF-H is less sensitive to cadmium toxicity in melanocyte-linage cells. • Cadmium does not decrease the expression of MITF-H in retinal pigment epithelial cells. • MITF-M is the molecular target of cadmium toxicity in melanocytes. - Abstract: Dietary intake of cadmium is inevitable, causing age-related increase in cadmium accumulation in many organs, including hair, choroid and retinal pigment epithelium (RPE). Cadmium has been implicated in the pathogenesis of hearing loss and macular degeneration. The functions of cochlea and retina are maintained by melanocytes and RPE, respectively, and the differentiation of these pigment cells is regulated by microphthalmia-associated transcription factor (MITF). In the present study, we explored the potential toxicity of cadmium in the cochlea and retina by using cultured human melanocytes and human RPE cell lines. MITF consists of multiple isoforms, including melanocyte-specific MITF-M and widely expressed MITF-H. Levels of MITF-M protein and its mRNA in human epidermal melanocytes and HMV-II melanoma cells were decreased significantly by cadmium. In parallel with the MITF reduction, mRNA levels of tyrosinase, the key enzyme of melanin biosynthesis that is regulated by MITF-M, were also decreased. In RPE cells, however, the levels of total MITF protein, constituting mainly MITF-H, were not decreased by cadmium. We thus identify MITF-M as the molecular target of cadmium toxicity in melanocytes, thereby accounting for the increased risk of disability from melanocyte malfunction, such as hearing and vision loss among people with elevated cadmium exposure

  4. Microphthalmia-associated transcription factor as the molecular target of cadmium toxicity in human melanocytes

    Energy Technology Data Exchange (ETDEWEB)

    Chantarawong, Wipa [Department of Molecular Biology and Applied Physiology, Tohoku University School of Medicine, Sendai (Japan); Inter Departmental Multidisciplinary Graduate Program in Bioscience, Faculty of Science, Kasetsart University, Bangkok (Thailand); Takeda, Kazuhisa; Sangartit, Weerapon; Yoshizawa, Miki [Department of Molecular Biology and Applied Physiology, Tohoku University School of Medicine, Sendai (Japan); Pradermwong, Kantimanee [Department of Zoology, Faculty of Science, Kasetsart University, Bangkok (Thailand); Shibahara, Shigeki, E-mail: shibahar@med.tohoku.ac.jp [Department of Molecular Biology and Applied Physiology, Tohoku University School of Medicine, Sendai (Japan)

    2014-11-28

    Highlights: • In human melanocytes, cadmium decreases the expression of MITF-M and tyrosinase and their mRNAs. • In human melanoma cells, cadmium decreases the expression of MITF-M protein and tyrosinase mRNA. • Expression of MITF-H is less sensitive to cadmium toxicity in melanocyte-linage cells. • Cadmium does not decrease the expression of MITF-H in retinal pigment epithelial cells. • MITF-M is the molecular target of cadmium toxicity in melanocytes. - Abstract: Dietary intake of cadmium is inevitable, causing age-related increase in cadmium accumulation in many organs, including hair, choroid and retinal pigment epithelium (RPE). Cadmium has been implicated in the pathogenesis of hearing loss and macular degeneration. The functions of cochlea and retina are maintained by melanocytes and RPE, respectively, and the differentiation of these pigment cells is regulated by microphthalmia-associated transcription factor (MITF). In the present study, we explored the potential toxicity of cadmium in the cochlea and retina by using cultured human melanocytes and human RPE cell lines. MITF consists of multiple isoforms, including melanocyte-specific MITF-M and widely expressed MITF-H. Levels of MITF-M protein and its mRNA in human epidermal melanocytes and HMV-II melanoma cells were decreased significantly by cadmium. In parallel with the MITF reduction, mRNA levels of tyrosinase, the key enzyme of melanin biosynthesis that is regulated by MITF-M, were also decreased. In RPE cells, however, the levels of total MITF protein, constituting mainly MITF-H, were not decreased by cadmium. We thus identify MITF-M as the molecular target of cadmium toxicity in melanocytes, thereby accounting for the increased risk of disability from melanocyte malfunction, such as hearing and vision loss among people with elevated cadmium exposure.

  5. Lycopene inhibits ICAM-1 expression and NF-κB activation by Nrf2-regulated cell redox state in human retinal pigment epithelial cells.

    Science.gov (United States)

    Yang, Po-Min; Wu, Zhi-Zhen; Zhang, Yu-Qi; Wung, Being-Sun

    2016-06-15

    Age-related macular degeneration (AMD) is one of the most common diseases leading to blindness in elderly people. The progression of AMD may be prevented through anti-inflammation and antioxidation in retinal pigment epithelium (RPE) cells. Lycopene, a carotenoid, has been shown to possess both antioxidative and anti-inflammatory properties. This research was conducted to detail the mechanisms of these effects of lycopene-treated RPE cells. We exposed ARPE-19 cells to TNFα after pretreatment with lycopene, and measured monocyte adhesion, ICAM-1 expression, NF-κB nuclear translocation, and transcriptional activity. Cell viability was assayed with Alamar Blue. The cell redox state was tested by glutathione (GSH) and reactive oxygen species (ROS) levels. The importance of the Nrf2 pathway was tested in nuclear translocation, promoter reporter assay, and siRNA. Lycopene could reduce TNF-α-induced monocyte adhesion and H2O2- induced cell damage in RPE cells. Furthermore, lycopene inhibits ICAM-1 expression and abolishes NF-κB activation for up to 12h in TNFα-treated RPE cells. Lycopene upregulates Nrf2 levels in nuclear extracts and increases the transactivity of antioxidant response elements. The use of Nrf2 siRNA blocks the inhibitory effect of lycopene in TNF-α-induced ICAM-1 expression and NF-κB activation. Glutamate-cysteine ligase (GCL) is the rate-limiting enzyme in the de novo synthesis of GSH. We found that lycopene increases intracellular GSH levels and GCL expression. Following lycopene treatment, TNF-α-induced ROS production was abolished. The Nrf2-regulated antioxidant property plays a pivotal role in the anti-inflammatory mechanism underlying the inhibition of NF-κB activation in lycopene-treated ARPE-19 cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. The 3' untranslated region of the cyclin B mRNA is not sufficient to enhance the synthesis of cyclin B during a mitotic block in human cells.

    Directory of Open Access Journals (Sweden)

    Dominik Schnerch

    Full Text Available Antimitotic agents are frequently used to treat solid tumors and hematologic malignancies. However, one major limitation of antimitotic approaches is mitotic slippage, which is driven by slow degradation of cyclin B during a mitotic block. The extent to which cyclin B levels decline is proposed to be governed by an equilibrium between cyclin B synthesis and degradation. It was recently shown that the 3' untranslated region (UTR of the murine cyclin B mRNA contributes to the synthesis of cyclin B during mitosis in murine cells. Using a novel live-cell imaging-based technique allowing us to study synthesis and degradation of cyclin B simultaneously at the single cell level, we tested here the role of the human cyclin B 3'UTR in regulating cyclin B synthesis during mitosis in human cells. We observed that the cyclin B 3'UTR was not sufficient to enhance cyclin B synthesis in human U2Os, HeLa or hTERT RPE-1 cells. A better understanding of how the equilibrium of cyclin B is regulated in mitosis may contribute to the development of improved therapeutic approaches to prevent mitotic slippage in cancer cells treated with antimitotic agents.

  7. Isolation of Human Innate Lymphoid Cells.

    Science.gov (United States)

    Krabbendam, Lisette; Nagasawa, Maho; Spits, Hergen; Bal, Suzanne M

    2018-06-29

    Innate lymphoid cells (ILCs) are innate immune cells of lymphoid origin that have important effector and regulatory functions in the first line of defense against pathogens, but also regulate tissue homeostasis, remodeling, and repair. Their function mirrors T helper cells and cytotoxic CD8 + T lymphocytes, but they lack expression of rearranged antigen-specific receptors. Distinct ILC subsets are classified in group 1 ILCs (ILC1s), group 2 ILCs (ILC2s), and group 3 ILCs (ILC3s and lymphoid tissue-inducer cells), based on the expression of transcription factors and the cytokines they produce. As the frequency of ILCs is low, their isolation requires extensive depletion of other cell types. The lack of unique cell surface antigens further complicates the identification of these cells. Here, methods for ILC isolation and characterization from human peripheral blood and different tissues are described. © 2018 by John Wiley & Sons, Inc. © 2018 John Wiley & Sons, Inc.

  8. Incorporation of Human Recombinant Tropoelastin into Silk Fibroin Membranes with the View to Repairing Bruch’s Membrane

    Directory of Open Access Journals (Sweden)

    Audra M. A. Shadforth

    2015-09-01

    Full Text Available Bombyx mori silk fibroin membranes provide a potential delivery vehicle for both cells and extracellular matrix (ECM components into diseased or injured tissues. We have previously demonstrated the feasibility of growing retinal pigment epithelial cells (RPE on fibroin membranes with the view to repairing the retina of patients afflicted with age-related macular degeneration (AMD. The goal of the present study was to investigate the feasibility of incorporating the ECM component elastin, in the form of human recombinant tropoelastin, into these same membranes. Two basic strategies were explored: (1 membranes prepared from blended solutions of fibroin and tropoelastin; and (2 layered constructs prepared from sequentially cast solutions of fibroin, tropoelastin, and fibroin. Optimal conditions for RPE attachment were achieved using a tropoelastin-fibroin blend ratio of 10 to 90 parts by weight. Retention of tropoelastin within the blend and layered constructs was confirmed by immunolabelling and Fourier-transform infrared spectroscopy (FTIR. In the layered constructs, the bulk of tropoelastin was apparently absorbed into the initially cast fibroin layer. Blend membranes displayed higher elastic modulus, percentage elongation, and tensile strength (p < 0.01 when compared to the layered constructs. RPE cell response to fibroin membranes was not affected by the presence of tropoelastin. These findings support the potential use of fibroin membranes for the co-delivery of RPE cells and tropoelastin.

  9. RPE65 gene: multiplex PCR and mutation screening in patients from ...

    Indian Academy of Sciences (India)

    Unknown

    The RPE65 protein is believed to play an important role in the metabolism of vitamin A in the ... PCR and mutation screening in patients from India with retinal degenerative diseases. ..... Bennett J. 2001 Gene therapy restores vision in a canine.

  10. Identification of a class of nonlinear state-space models using RPE techniques

    DEFF Research Database (Denmark)

    Zhou, W. W.; Blanke, Mogens

    1986-01-01

    The recursive prediction error methods in state-space form have been efficiently used as parameter identifiers for linear systems, and especially Ljung's innovations filter using a Newton search direction has proved to be quite ideal. In this paper, the RPE method in state-space form is developed...... a quite convincing performance of the filter as combined parameter and state estimator....

  11. Session-RPE for quantifying the load of different youth basketball training sessions.

    Science.gov (United States)

    Lupo, C; Tessitore, A; Gasperi, L; Gomez, Mar

    2017-03-01

    The aim of the study was to evaluate youth basketball training, verifying the reliability of the session-RPE method in relation to session duration (session) categories. Six male youth basketball players (age, 16.5±0.5 years; height, 195.5±6.75 cm; body mass, 93.9±10.9 kg; and body mass index, 23.6±2.8 kg.m -2 ) were monitored (HR, type and duration of workouts) during 15 (66 individual) training sessions (80±26 minutes). Edwards' HR method was used as a reference measure of internal training load (ITL); the CR-10 RPE scale was administered 30 minutes after the end of each session. The results obtained showed that all comparisons between different session durations and workout portions revealed effects in term of Edwards' ITLs except for warm-up portions. Moderate to strong relationships between Edwards' and session- RPE methods emerged for all sessions (r = .85, P sessions (r range = .79 - .95, P session durations (session-RPE to monitor the ITL, regardless of session durations and workout portions.

  12. rpe v5: an emulator for reduced floating-point precision in large numerical simulations

    Science.gov (United States)

    Dawson, Andrew; Düben, Peter D.

    2017-06-01

    This paper describes the rpe (reduced-precision emulator) library which has the capability to emulate the use of arbitrary reduced floating-point precision within large numerical models written in Fortran. The rpe software allows model developers to test how reduced floating-point precision affects the result of their simulations without having to make extensive code changes or port the model onto specialized hardware. The software can be used to identify parts of a program that are problematic for numerical precision and to guide changes to the program to allow a stronger reduction in precision.The development of rpe was motivated by the strong demand for more computing power. If numerical precision can be reduced for an application under consideration while still achieving results of acceptable quality, computational cost can be reduced, since a reduction in numerical precision may allow an increase in performance or a reduction in power consumption. For simulations with weather and climate models, savings due to a reduction in precision could be reinvested to allow model simulations at higher spatial resolution or complexity, or to increase the number of ensemble members to improve predictions. rpe was developed with a particular focus on the community of weather and climate modelling, but the software could be used with numerical simulations from other domains.

  13. Session-RPE for quantifying the load of different youth basketball training sessions

    Directory of Open Access Journals (Sweden)

    C Lupo

    2016-12-01

    Full Text Available The aim of the study was to evaluate youth basketball training, verifying the reliability of the session-RPE method in relation to session duration (< and ≥ 80 minutes and workout typology (reduced and high warm-up, conditioning, technical, tactical, game portions within a single session categories. Six male youth basketball players (age, 16.5±0.5 years; height, 195.5±6.75 cm; body mass, 93.9±10.9 kg; and body mass index, 23.6±2.8 kg.m-2 were monitored (HR, type and duration of workouts during 15 (66 individual training sessions (80±26 minutes. Edwards’ HR method was used as a reference measure of internal training load (ITL; the CR-10 RPE scale was administered 30 minutes after the end of each session. The results obtained showed that all comparisons between different session durations and workout portions revealed effects in term of Edwards’ ITLs except for warm-up portions. Moderate to strong relationships between Edwards’ and session- RPE methods emerged for all sessions (r = .85, P < .001, player’s sessions (r range = .79 - .95, P < .001, session durations (< 80 minutes: r = .67, P < .001; ≥ 80 minutes: r = .75, P < .001, and workout portions (r range = .78 - .89, P range = .002 - < .001. The findings indicated that coaches of youth basketball players can successfully use session-RPE to monitor the ITL, regardless of session durations and workout portions.

  14. Human CD56bright NK Cells

    DEFF Research Database (Denmark)

    Michel, Tatiana; Poli, Aurélie; Cuapio, Angelica

    2016-01-01

    Human NK cells can be subdivided into various subsets based on the relative expression of CD16 and CD56. In particular, CD56(bright)CD16(-/dim) NK cells are the focus of interest. They are considered efficient cytokine producers endowed with immunoregulatory properties, but they can also become c...... NK cell subsets is not fully defined, nor is their precise hematopoietic origin. In this article, we summarize recent studies about CD56(bright) NK cells in health and disease and briefly discuss the current controversies surrounding them....

  15. Evaluating human cancer cell metastasis in zebrafish

    International Nuclear Information System (INIS)

    Teng, Yong; Xie, Xiayang; Walker, Steven; White, David T; Mumm, Jeff S; Cowell, John K

    2013-01-01

    In vivo metastasis assays have traditionally been performed in mice, but the process is inefficient and costly. However, since zebrafish do not develop an adaptive immune system until 14 days post-fertilization, human cancer cells can survive and metastasize when transplanted into zebrafish larvae. Despite isolated reports, there has been no systematic evaluation of the robustness of this system to date. Individual cell lines were stained with CM-Dil and injected into the perivitelline space of 2-day old zebrafish larvae. After 2-4 days fish were imaged using confocal microscopy and the number of metastatic cells was determined using Fiji software. To determine whether zebrafish can faithfully report metastatic potential in human cancer cells, we injected a series of cells with different metastatic potential into the perivitelline space of 2 day old embryos. Using cells from breast, prostate, colon and pancreas we demonstrated that the degree of cell metastasis in fish is proportional to their invasion potential in vitro. Highly metastatic cells such as MDA231, DU145, SW620 and ASPC-1 are seen in the vasculature and throughout the body of the fish after only 24–48 hours. Importantly, cells that are not invasive in vitro such as T47D, LNCaP and HT29 do not metastasize in fish. Inactivation of JAK1/2 in fibrosarcoma cells leads to loss of invasion in vitro and metastasis in vivo, and in zebrafish these cells show limited spread throughout the zebrafish body compared with the highly metastatic parental cells. Further, knockdown of WASF3 in DU145 cells which leads to loss of invasion in vitro and metastasis in vivo also results in suppression of metastasis in zebrafish. In a cancer progression model involving normal MCF10A breast epithelial cells, the degree of invasion/metastasis in vitro and in mice is mirrored in zebrafish. Using a modified version of Fiji software, it is possible to quantify individual metastatic cells in the transparent larvae to correlate with

  16. Guanine nucleotide-binding regulatory proteins in retinal pigment epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Meisheng; Tran, V.T.; Fong, H.K.W. (Univ. of Southern California, Los Angeles (United States)); Pandey, S. (Doheny Eye Inst., Los Angeles, CA (United States))

    1991-05-01

    The expression of GTP-binding regulatory proteins (G proteins) in retinal pigment epithelial (RPE) cells was analyzed by RNA blot hybridization and cDNA amplification. Both adult and fetal human RPE cells contain mRNA for multiple G protein {alpha} subunits (G{alpha}) including G{sub s}{alpha}, G{sub i-1}{alpha}, G{sub i-2}{alpha}, G{sub i-3}{alpha}, and G{sub z}{alpha} (or G{sub x}{alpha}), where G{sub s} and G{sub i} are proteins that stimulate or inhibit adenylyl cyclase, respectively, and G{sub z} is a protein that may mediate pertussis toxin-insensitive events. Other G{alpha}-related mRNA transcripts were detected in fetal RPE cells by low-stringency hybridization to G{sub i-2}{alpha} and G{sub s}{alpha} protein-coding cDNA probes. The diversity of G proteins in RPE cells was further studied by cDNA amplification with reverse transcriptase and the polymerase chain reaction. This approach revealed that, besides the above mentioned members of the G{alpha} gene family, at least two other G{alpha} subunits are expressed in RPE cells. Human retinal cDNA clones that encode one of the additional G{alpha} subunits were isolated and characterized. The results indicate that this G{alpha} subunit belongs to a separate subfamily of G proteins that may be insensitive to inhibition by pertussis toxin.

  17. Shape Analysis of the Peripapillary RPE Layer in Papilledema and Ischemic Optic Neuropathy

    Science.gov (United States)

    Kupersmith, Mark J.; Rohlf, F. James

    2011-01-01

    Purpose. Geometric morphometrics (GM) was used to analyze the shape of the peripapillary retinal pigment epithelium–Bruch's membrane (RPE/BM) layer imaged on the SD-OCT 5-line raster in normal subjects and in patients with papilledema and ischemic optic neuropathy. Methods. Three groups of subjects were compared: 30 normals, 20 with anterior ischemic optic neuropathy (AION), and 25 with papilledema and intracranial hypertension. Twenty equidistant semilandmarks were digitized on OCT images of the RPE/BM layer spanning 2500 μm on each side of the neural canal opening (NCO). The data were analyzed using standard GM techniques, including a generalized least-squares Procrustes superimposition, principal component analysis, thin-plate spline (to visualize deformations), and permutation statistical analysis to evaluate differences in shape variables. Results. The RPE/BM layer in normals and AION have a characteristic V shape pointing away from the vitreous; the RPE/BM layer in papilledema has an inverted U shape, skewed nasally inward toward the vitreous. The differences were statistically significant. There was no significant difference in shapes between normals and AION. Pre- and posttreatment OCTs, in select cases of papilledema, showed that the inverted U-shaped RPE/BM moved posteriorly into a normal V shape as the papilledema resolved with weight loss or shunting. Conclusions. The shape difference in papilledema, absent in AION, cannot be explained by disc edema alone. The difference is a consequence of both the translaminar pressure gradient and the material properties of the peripapillary sclera. GM offers a novel way of statistically assessing shape differences of the peripapillary optic nerve head. PMID:21896851

  18. Session-RPE for quantifying load of different youth taekwondo training sessions.

    Science.gov (United States)

    Lupo, Corrado; Capranica, Laura; Cortis, Cristina; Guidotti, Flavia; Bianco, Antonino; Tessitore, Antonio

    2017-03-01

    The session rating of perceived exertion (session-RPE) proved to be a valuable method to quantify the internal training load (ITL) in taekwondo. However, no study validated this method in youth taekwondo athletes performing different training sessions. Thus this study aimed at evaluating the reliability of the session-RPE to monitor the ITL of prepubescent taekwondo athletes during pre-competitive (PC) and competitive (C) training sessions. Five female (age: 12.0±0.7 y; height: 1.54±0.08 m; body mass: 48.8±7.3 kg) and four male (age: 12.0±0.8 yrs; height: 1.55±0.07 m; body mass: 47.3±5.3 kg) taekwondo athletes were monitored during 100 individual sessions (PC: N.=33; C: N.=67). The Edwards' HR method was used as reference measure of ITL; the CR-10 RPE scale was administered at 1- and 30-minutes from the end of each session. No difference for gender emerged. The ITLs of C (Edwards: 228±40 arbitrary units, AU) resulted higher than that of PC (192±26 AU; P=0.04). Although all training typologies and data collections achieved significant correlations between Edwards' and session-RPE methods, a large relationship (r =0.71, Psessions evaluated at 30 minutes of the recovery phases. Findings support coaches of prepubescent taekwondo athletes to successfully use session-RPE to monitor the ITL of different training typologies. However, PC training evaluated at 30 minutes of the recovery phase represents the best condition for a highly reliable ITL perception.

  19. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins

    OpenAIRE

    Hayato Fukusumi; Tomoko Shofuda; Yohei Bamba; Atsuyo Yamamoto; Daisuke Kanematsu; Yukako Handa; Keisuke Okita; Masaya Nakamura; Shinya Yamanaka; Hideyuki Okano; Yonehiro Kanemura

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPS...

  20. Human Mammary Luminal Epithelial Cells Contain Progenitors to Myoepithelial Cells

    Energy Technology Data Exchange (ETDEWEB)

    Pechoux, Christine; Gudjonsson, Thorarinn; Ronnov-Jessen, Lone; Bissell, Mina J; Petersen, Ole

    1999-02-01

    The origin of the epithelial and myoepithelial cells in the human breast has not been delineated. In this study we have addressed whether luminal epithelial cells and myoepithelial cells are vertically connected, i.e., whether one is the precursor for the other. We used a primary culture assay allowing preservation of basic phenotypic traits of luminal epithelial and myoepithelial cells in culture. The two cell types were then separated immunomagnetically using antibodies directed against lineage-specific cell surface antigens into at best 100% purity. The cellular identity was ascertained by cytochemistry, immunoblotting, and 2-D gel electrophoresis. Luminal epithelial cells were identified by strong expression of cytokeratins 18 and 19 while myoepithelial cells were recognized by expression of vimentin and {alpha}-smooth muscle actin. We used a previously devised culture medium (CDM4) that allows vigorous expansion of proliferative myoepithelial cells and also devised a medium (CDM6) that allowed sufficient expansion of differentiated luminal epithelial cells based on addition of hepatocyte growth factor/scatter factor. The two different culture media supported each lineage for at least five passages without signs of interconversion. We used parallel cultures where we switched culture media, thus testing the ability of each lineage to convert to the other. Whereas the myoepithelial lineage showed no signs of interconversion, a subset of luminal epithelial cells, gradually, but distinctly, converted to myoepithelial cells. We propose that in the mature human breast, it is the luminal epithelial cell compartment that gives rise to myoepithelial cells rather than the other way around.

  1. 3 CFR - Guidelines for Human Stem Cell Research

    Science.gov (United States)

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false Guidelines for Human Stem Cell Research Presidential Documents Other Presidential Documents Memorandum of July 30, 2009 Guidelines for Human Stem Cell Research..., scientifically worthy human stem cell research, including human embryonic stem cell research, to the extent...

  2. 21 CFR 864.2280 - Cultured animal and human cells.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cultured animal and human cells. 864.2280 Section... Cultured animal and human cells. (a) Identification. Cultured animal and human cells are in vitro cultivated cell lines from the tissue of humans or other animals which are used in various diagnostic...

  3. Cell pattern in adult human corneal endothelium.

    Directory of Open Access Journals (Sweden)

    Carlos H Wörner

    Full Text Available A review of the current data on the cell density of normal adult human endothelial cells was carried out in order to establish some common parameters appearing in the different considered populations. From the analysis of cell growth patterns, it is inferred that the cell aging rate is similar for each of the different considered populations. Also, the morphology, the cell distribution and the tendency to hexagonallity are studied. The results are consistent with the hypothesis that this phenomenon is analogous with cell behavior in other structures such as dry foams and grains in polycrystalline materials. Therefore, its driving force may be controlled by the surface tension and the mobility of the boundaries.

  4. Merkel cell distribution in the human eyelid

    Directory of Open Access Journals (Sweden)

    C.A. May

    2013-10-01

    Full Text Available Although Merkel cell carcinoma of the eye lid is reported frequently in the literature, only limited information exists about the distribution of Merkel cells in this tissue. Therefore, serial sections of 18 human cadaver eye lids (donors ages ranging between 63 and 97 years were stained for cytokeratin 20 in various planes. The overall appearance of Merkel cells in these samples was low and mainly located in the outer root layer of the cilia hair follicles. Merkel cells were more frequent in the middle, and almost not detectable at the nasal and temporal edges. The localization is in accordance with that of Merkel cell carcinoma, but concerning the scarce appearance within this adulthood group, a specific physiological role of these cells in the eye lid is difficult to establish.

  5. Haemopoietic progenitor cells in human peripheral blood

    International Nuclear Information System (INIS)

    Zwaan, F.E.

    1980-01-01

    The purpose of the investigation reported is to purify haemopoietic progenitor cells from human peripheral blood using density gradient centrifugation in order to isolate a progenitor cell fraction without immunocompetent cells. The purification technique of peripheral blood flow colony forming unit culture (CFU-c) by means of density gradient centrifugation and a combined depletion of various rosettes is described. The results of several 'in vitro' characteristics of purified CFU-c suspensions and of the plasma clot diffusion chamber culture technique are presented. Irradiation studies revealed that for both human bone marrow and peripheral blood the CFU-c were less radioresistant than clusters. Elimination of monocytes (and granulocytes) from the test suspensions induced an alteration in radiosensitivity pararmeters. The results obtained with the different techniques are described by analysing peripheral progenitor cell activity in myeloproliferative disorders. (Auth.)

  6. T-cell response in human leishmaniasis

    DEFF Research Database (Denmark)

    Kharazmi, A; Kemp, K; Ismail, A

    1999-01-01

    In the present communication we provide evidence for the existence of a Th1/Th2 dichotomy in the T-cell response to Leishmania antigens in human leishmaniasis. Our data suggest that the pattern of IL-4 and IFN-gamma response is polarised in these patients. Lymphocytes from individuals recovered...... from cutaneous leishmaniasis (CL) responded by IFN-gamma production following stimulation with Leishmania antigens whereas cells from patients recovered from visceral leishmaniasis (VL) showed a mixed pattern of IFN-gamma and IL-4 responses. The cells producing these cytokines were predominantly CD4......+. Furthermore, IL-10 plays an important role in the development of post kala azar dermal leishmaniasis (PKDL) from VL. The balance between the parasitic-specific T-cell response plays an important regulatory role in determining the outcome of Leishmania infections in humans....

  7. Lobaplatin arrests cell cycle progression in human hepatocellular carcinoma cells

    Directory of Open Access Journals (Sweden)

    Chen Chang-Jie

    2010-10-01

    Full Text Available Abstract Background Hepatocellular carcinoma (HCC still is a big burden for China. In recent years, the third-generation platinum compounds have been proposed as potential active agents for HCC. However, more experimental and clinical data are warranted to support the proposal. In the present study, the effect of lobaplatin was assessed in five HCC cell lines and the underlying molecular mechanisms in terms of cell cycle kinetics were explored. Methods Cytotoxicity of lobaplatin to human HCC cell lines was examined using MTT cell proliferation assay. Cell cycle distribution was determined by flow cytometry. Expression of cell cycle-regulated genes was examined at both the mRNA (RT-PCR and protein (Western blot levels. The phosphorylation status of cyclin-dependent kinases (CDKs and retinoblastoma (Rb protein was also examined using Western blot analysis. Results Lobaplatin inhibited proliferation of human HCC cells in a dose-dependent manner. For the most sensitive SMMC-7721 cells, lobaplatin arrested cell cycle progression in G1 and G2/M phases time-dependently which might be associated with the down-regulation of cyclin B, CDK1, CDC25C, phosphorylated CDK1 (pCDK1, pCDK4, Rb, E2F, and pRb, and the up-regulation of p53, p21, and p27. Conclusion Cytotoxicity of lobaplatin in human HCC cells might be due to its ability to arrest cell cycle progression which would contribute to the potential use of lobaplatin for the management of HCC.

  8. Fisetin induces apoptosis through mitochondrial apoptosis pathway in human uveal melanoma cells.

    Science.gov (United States)

    Wang, Kai; Hu, Dan-Ning; Lin, Hui-Wen; Yang, Wei-En; Hsieh, Yi-Hsien; Chien, Hsiang-Wen; Yang, Shun-Fa

    2018-05-01

    Fisetin, a diatery flavonoid, been reported that possess anticancer effects in various cancers. The purpose of the study was to investigate the antitumor effects of fisetin in cultured uveal melanoma cell lines and compared with normal retinal pigment epithelial (RPE) cells. MTT assay was used for evaluating cytotoxic effects of fisetin. Flow cytometry study was used for the determination of apoptosis. JC-1 fluorescent reader was used to determine mitochondrial transmembrane potential changes. The results shown that fisetin dose-dependently decreased the cell viability of uveal melanoma cells but not influenced the cell viability of RPE cells. Apoptosis of uveal melanoma cells was induced by fisetin efficiently. Fisetin inhibited antiapoptotic Bcl-2 family proteins and damaged the mitochondrial transmembrane potential. The levels of proapoptotic Bcl-2 proteins, cytochrome c, and various caspase activities were increased by fisetin. In conclusion, fisetin induces apoptosis of uveal melanoma cells selectively and may be a promising agent to be explored for the treatment of uveal melanoma. © 2018 Wiley Periodicals, Inc.

  9. A comparison of some organizational characteristics of the mouse central retina and the human macula.

    Science.gov (United States)

    Volland, Stefanie; Esteve-Rudd, Julian; Hoo, Juyea; Yee, Claudine; Williams, David S

    2015-01-01

    Mouse models have greatly assisted our understanding of retinal degenerations. However, the mouse retina does not have a macula, leading to the question of whether the mouse is a relevant model for macular degeneration. In the present study, a quantitative comparison between the organization of the central mouse retina and the human macula was made, focusing on some structural characteristics that have been suggested to be important in predisposing the macula to stresses leading to degeneration: photoreceptor density, phagocytic load on the RPE, and the relative thinness of Bruch's membrane. Light and electron microscopy measurements from retinas of two strains of mice, together with published data on human retinas, were used for calculations and subsequent comparisons. As in the human retina, the central region of the mouse retina possesses a higher photoreceptor cell density and a thinner Bruch's membrane than in the periphery; however, the magnitudes of these periphery to center gradients are larger in the human. Of potentially greater relevance is the actual photoreceptor cell density, which is much greater in the mouse central retina than in the human macula, underlying a higher phagocytic load for the mouse RPE. Moreover, at eccentricities that correspond to the peripheral half of the human macula, the rod to cone ratio is similar between mouse and human. Hence, with respect to photoreceptor density and phagocytic load of the RPE, the central mouse retina models at least the more peripheral part of the macula, where macular degeneration is often first evident.

  10. Shape Memory of Human Red Blood Cells

    OpenAIRE

    Fischer, Thomas M.

    2004-01-01

    The human red cell can be deformed by external forces but returns to the biconcave resting shape after removal of the forces. If after such shape excursions the rim is always formed by the same part of the membrane, the cell is said to have a memory of its biconcave shape. If the rim can form anywhere on the membrane, the cell would have no shape memory. The shape memory was probed by an experiment called go-and-stop. Locations on the membrane were marked by spontaneously adhering latex spher...

  11. ROCK-1 mediates diabetes-induced retinal pigment epithelial and endothelial cell blebbing: Contribution to diabetic retinopathy.

    Science.gov (United States)

    Rothschild, Pierre-Raphaël; Salah, Sawsen; Berdugo, Marianne; Gélizé, Emmanuelle; Delaunay, Kimberley; Naud, Marie-Christine; Klein, Christophe; Moulin, Alexandre; Savoldelli, Michèle; Bergin, Ciara; Jeanny, Jean-Claude; Jonet, Laurent; Arsenijevic, Yvan; Behar-Cohen, Francine; Crisanti, Patricia

    2017-08-18

    In diabetic retinopathy, the exact mechanisms leading to retinal capillary closure and to retinal barriers breakdown remain imperfectly understood. Rho-associated kinase (ROCK), an effector of the small GTPase Rho, involved in cytoskeleton dynamic regulation and cell polarity is activated by hyperglycemia. In one year-old Goto Kakizaki (GK) type 2 diabetic rats retina, ROCK-1 activation was assessed by its cellular distribution and by phosphorylation of its substrates, MYPT1 and MLC. In both GK rat and in human type 2 diabetic retinas, ROCK-1 is activated and associated with non-apoptotic membrane blebbing in retinal vessels and in retinal pigment epithelium (RPE) that respectively form the inner and the outer barriers. Activation of ROCK-1 induces focal vascular constrictions, endoluminal blebbing and subsequent retinal hypoxia. In RPE cells, actin cytoskeleton remodeling and membrane blebs in RPE cells contributes to outer barrier breakdown. Intraocular injection of fasudil, significantly reduces both retinal hypoxia and RPE barrier breakdown. Diabetes-induced cell blebbing may contribute to ischemic maculopathy and represent an intervention target.

  12. Human embryonic stem cell lines model experimental human cytomegalovirus latency.

    Science.gov (United States)

    Penkert, Rhiannon R; Kalejta, Robert F

    2013-05-28

    Herpesviruses are highly successful pathogens that persist for the lifetime of their hosts primarily because of their ability to establish and maintain latent infections from which the virus is capable of productively reactivating. Human cytomegalovirus (HCMV), a betaherpesvirus, establishes latency in CD34(+) hematopoietic progenitor cells during natural infections in the body. Experimental infection of CD34(+) cells ex vivo has demonstrated that expression of the viral gene products that drive productive infection is silenced by an intrinsic immune defense mediated by Daxx and histone deacetylases through heterochromatinization of the viral genome during the establishment of latency. Additional mechanistic details about the establishment, let alone maintenance and reactivation, of HCMV latency remain scarce. This is partly due to the technical challenges of CD34(+) cell culture, most notably, the difficulty in preventing spontaneous differentiation that drives reactivation and renders them permissive for productive infection. Here we demonstrate that HCMV can establish, maintain, and reactivate in vitro from experimental latency in cultures of human embryonic stem cells (ESCs), for which spurious differentiation can be prevented or controlled. Furthermore, we show that known molecular aspects of HCMV latency are faithfully recapitulated in these cells. In total, we present ESCs as a novel, tractable model for studies of HCMV latency.

  13. Human embryonic stem cells: preclinical perspectives

    Directory of Open Access Journals (Sweden)

    Sarda Kanchan

    2008-01-01

    Full Text Available Abstract Human embryonic stem cells (hESCs have been extensively discussed in public and scientific communities for their potential in treating diseases and injuries. However, not much has been achieved in turning them into safe therapeutic agents. The hurdles in transforming hESCs to therapies start right with the way these cells are derived and maintained in the laboratory, and goes up-to clinical complications related to need for patient specific cell lines, gender specific aspects, age of the cells, and several post transplantation uncertainties. The different types of cells derived through directed differentiation of hESC and used successfully in animal disease and injury models are described briefly. This review gives a brief outlook on the present and the future of hESC based therapies, and talks about the technological advances required for a safe transition from laboratory to clinic.

  14. Neocortical glial cell numbers in human brains

    DEFF Research Database (Denmark)

    Pelvig, D.P.; Pakkenberg, H.; Stark, A.K.

    2008-01-01

    Stereological cell counting was applied to post-mortem neocortices of human brains from 31 normal individuals, age 18-93 years, 18 females (average age 65 years, range 18-93) and 13 males (average age 57 years, range 19-87). The cells were differentiated in astrocytes, oligodendrocytes, microglia...... while the total astrocyte number is constant through life; finally males have a 28% higher number of neocortical glial cells and a 19% higher neocortical neuron number than females. The overall total number of neocortical neurons and glial cells was 49.3 billion in females and 65.2 billion in males...... and neurons and counting were done in each of the four lobes. The study showed that the different subpopulations of glial cells behave differently as a function of age; the number of oligodendrocytes showed a significant 27% decrease over adult life and a strong correlation to the total number of neurons...

  15. Melanopsin expressing human retinal ganglion cells

    DEFF Research Database (Denmark)

    Hannibal, Jens; Christiansen, Anders Tolstrup; Heegaard, Steffen

    2017-01-01

    microscopy and 3D reconstruction of melanopsin immunoreactive (-ir) RGCs, we applied the criteria used in mouse on human melanopsin-ir RGCs. We identified M1, displaced M1, M2, and M4 cells. We found two other subtypes of melanopsin-ir RGCs, which were named "gigantic M1 (GM1)" and "gigantic displaced M1...

  16. Characterization of a spontaneously generated murine retinal pigmented epithelium cell line; a model for in vitro experiments.

    Science.gov (United States)

    Ranaei Pirmardan, Ehsan; Soheili, Zahra-Soheila; Samiei, Shahram; Ahmadieh, Hamid; Mowla, Seyed Javad; Ezzati, Razie; Naseri, Marzieh

    2016-10-01

    Retinal pigmented epithelium (RPE), the outermost layer of the retina, has a key role in maintaining retinal cells' functions. Severity of the culture of RPE cells has exerted many limitations to both in vitro and in vivo studies and its therapeutic applications. Therefore, establishment of RPE cell lines with high proliferative potential can considerably improve study of RPE cell biology. Here we report generation of a spontaneously immortalized murine RPE cell line in primary mouse RPE cell culture. Founded colonized cells were picked up and expression of RPE and retinal progenitor cells' (RPC) markers were studied using immunocytochemistry (ICC). Emerged cells cultured over 35 passages and population doubling times in different serum concentrations were calculated. We also investigated the ability of cells for becoming transfected by calcium-phosphate method and for becoming infected by adeno-associated virus serotype 2 (AAV2) using flow cytometry. Data showed that the cobblestone constituent cells expressed RPE65, cytokeratin and ZO1 and moreover several progenitor markers such as Pax6, Sox2, Nestin and Chx10. It revealed that, despite primary RPE cells, the newly emerged cells were easily transfectable and were highly infectable when compared with HEK293T cells. Our data indicated that the emerged mouse RPE cell line pretended RPC-like phenotype and also simultaneously expressed RPE markers. It would be a promising model for leading studies on RPE and RPC cells and substantially confirmed the great RPE plasticity and its invaluable potential in research studies. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Clinical potentials of human pluripotent stem cells.

    Science.gov (United States)

    Mora, Cristina; Serzanti, Marialaura; Consiglio, Antonella; Memo, Maurizio; Dell'Era, Patrizia

    2017-08-01

    Aging, injuries, and diseases can be considered as the result of malfunctioning or damaged cells. Regenerative medicine aims to restore tissue homeostasis by repairing or replacing cells, tissues, or damaged organs, by linking and combining different disciplines including engineering, technology, biology, and medicine. To pursue these goals, the discipline is taking advantage of pluripotent stem cells (PSCs), a peculiar type of cell possessing the ability to differentiate into every cell type of the body. Human PSCs can be isolated from the blastocysts and maintained in culture indefinitely, giving rise to the so-called embryonic stem cells (ESCs). However, since 2006, it is possible to restore in an adult cell a pluripotent ESC-like condition by forcing the expression of four transcription factors with the rejuvenating reprogramming technology invented by Yamanaka. Then the two types of PSC can be differentiated, using standardized protocols, towards the cell type necessary for the regeneration. Although the use of these derivatives for therapeutic transplantation is still in the preliminary phase of safety and efficacy studies, a lot of efforts are presently taking place to discover the biological mechanisms underlying genetic pathologies, by differentiating induced PSCs derived from patients, and new therapies by challenging PSC-derived cells in drug screening.

  18. Pigment Production Analysis in Human Melanoma Cells.

    Science.gov (United States)

    Hopkin, Amelia Soto; Paterson, Elyse K; Ruiz, Rolando; Ganesan, Anand K

    2016-05-25

    The human epidermal melanocyte is a highly specialized pigmented cell that serves to protect the epidermis from ultraviolet (UV) damage through the production of melanin, or melanogenesis. Misregulation in melanogenesis leading to either hyper- or hypo-pigmentation is found in human diseases such as malasma and vitiligo. Current therapies for these diseases are largely unsuccessful and the need for new therapies is necessary. In order to identify genes and or compounds that can alter melanogenesis, methods are required that can detect changes in pigment production as well as expression of key melanogenesis transcription factors and enzymes. Here we describe methods to detect changes in melanogenesis in a human melanoma cell line, MNT-1, by (1) analyzing pigment production by measuring the absorbance of melanin present by spectrophotometry, (2) analyzing transcript expression of potent regulators of melanogenesis by qunatitative reverse-transcription (RT)PCR and (3) analyzing protein expression of potent regulators of melanogenesis by Western blot (WB).

  19. Human T Cell Memory: A Dynamic View

    Directory of Open Access Journals (Sweden)

    Derek C. Macallan

    2017-02-01

    Full Text Available Long-term T cell-mediated protection depends upon the formation of a pool of memory cells to protect against future pathogen challenge. In this review we argue that looking at T cell memory from a dynamic viewpoint can help in understanding how memory populations are maintained following pathogen exposure or vaccination. For example, a dynamic view resolves the apparent paradox between the relatively short lifespans of individual memory cells and very long-lived immunological memory by focussing on the persistence of clonal populations, rather than individual cells. Clonal survival is achieved by balancing proliferation, death and differentiation rates within and between identifiable phenotypic pools; such pools correspond broadly to sequential stages in the linear differentiation pathway. Each pool has its own characteristic kinetics, but only when considered as a population; single cells exhibit considerable heterogeneity. In humans, we tend to concentrate on circulating cells, but memory T cells in non-lymphoid tissues and bone marrow are increasingly recognised as critical for immune defence; their kinetics, however, remain largely unexplored. Considering vaccination from this viewpoint shifts the focus from the size of the primary response to the survival of the clone and enables identification of critical system pinch-points and opportunities to improve vaccine efficacy.

  20. Development and function of human innate immune cells in a humanized mouse model.

    Science.gov (United States)

    Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V; Teichmann, Lino L; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A Karolina; Manz, Markus G; Flavell, Richard A

    2014-04-01

    Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models cannot support development of human innate immune cells, including myeloid cells and natural killer (NK) cells. Here we describe two mouse strains called MITRG and MISTRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked into their respective mouse loci. The human cytokines support the development and function of monocytes, macrophages and NK cells derived from human fetal liver or adult CD34(+) progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MITRG and MISTRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology.

  1. Gait and posture analysis in patients with maxillary transverse discrepancy, before and after RPE.

    Science.gov (United States)

    Mason, Martina; Spolaor, Fabiola; Guiotto, Annamaria; De Stefani, Alberto; Gracco, Antonio; Sawacha, Zimi

    2018-03-01

    The purpose of this study was to evaluate the effects of the rapid palatal expansion (RPE) on posture and gait analysis in subjects with maxillary transverse discrepancies. Forty-one patients between 6 and 12 years were divided into 3 groups: 10 control subjects (Cs), 16 patients with unilateral posterior crossbite (CbMono), 15 patients with maxillary transverse discrepancy and no crossbite (Nocb). Every subject underwent gait analysis and posturographic examination in order to evaluate the presence of balance alterations before (T0) and after (T4) RPE application. The examinations were performed through a six-cameras stereophotogrammetric system (60-120Hz, BTS S.p.A.) synchronized with two force plates (FP4060, Bertec Corp.). Romberg test was performed on a force plate, and the statokinesiogram and joint kinematics were evaluated. One-way Anova was performed among the variables after evidence of normal distribution (Levene's test for equality of variances) and Kruskal-Wallis test (Ptest was performed, or Kruskal-Wallis test, instead when comparing pre- and post-RPE application within the same group of subjects (P<0.05). Tamane T2 or Bonferroni correction was applied where needed. The posturographic analysis reveal significant differences across the 3 population: 95% power frequency in medio-lateral and antero-posterior direction in T0, median frequency in medio-lateral direction in T0, mean power frequency in medio-lateral direction in T0. Significant differences were also registered in the three-dimensional joints kinematics variables, mainly between Cs and Cbmono in T0 and T4 and between Cbmono and Nocb in T4. A detectable correlation between dental occlusion and body posture is shown in this study that confirms another benefit of the RPE. This was mainly revealed in the dynamic posture where modifications at the mandibular level affect the whole body. Copyright © 2018. Published by Elsevier Masson SAS.

  2. Identification of a Class of Non-linear State Space Models using RPE Techniques

    DEFF Research Database (Denmark)

    Zhou, Wei-Wu; Blanke, Mogens

    1989-01-01

    The RPE (recursive prediction error) method in state-space form is developed in the nonlinear systems and extended to include the exact form of a nonlinearity, thus enabling structure preservation for certain classes of nonlinear systems. Both the discrete and the continuous-discrete versions...... of the algorithm in an innovations model are investigated, and a nonlinear simulation example shows a quite convincing performance of the filter as combined parameter and state estimator...

  3. RPE vs. Percentage 1RM Loading in Periodized Programs Matched for Sets and Repetitions

    Science.gov (United States)

    Helms, Eric R.; Byrnes, Ryan K.; Cooke, Daniel M.; Haischer, Michael H.; Carzoli, Joseph P.; Johnson, Trevor K.; Cross, Matthew R.; Cronin, John B.; Storey, Adam G.; Zourdos, Michael C.

    2018-01-01

    Purpose: To investigate differences between rating of perceived exertion (RPE) and percentage one-repetition maximum (1RM) load assignment in resistance-trained males (19–35 years) performing protocols with matched sets and repetitions differentiated by load-assignment. Methods: Participants performed squats then bench press 3x/weeks in a daily undulating format over 8-weeks. Participants were counterbalanced by pre-test 1RM then assigned to percentage 1RM (1RMG, n = 11); load-assignment via percentage 1RMs, or RPE groups (RPEG, n = 10); participant-selected loads to reach target RPE ranges. Ultrasonography determined pre and post-test pectoralis (PMT), and vastus lateralis muscle thickness at 50 (VLMT50) and 70% (VLMT70) femur-length. Results: Bench press (1RMG +9.64 ± 5.36; RPEG + 10.70 ± 3.30 kg), squat (1RMG + 13.91 ± 5.89; RPEG + 17.05 ± 5.44 kg) and their combined-total 1RMs (1RMG + 23.55 ± 10.38; RPEG + 27.75 ± 7.94 kg) increased (p 0.05). Magnitude-based inferences revealed 79, 57, and 72% chances of mean small effect size (ES) advantages for squat; ES 90% confidence limits (CL) = 0.50 ± 0.63, bench press; ES 90% CL = 0.28 ± 0.73, and combined-total; ES 90% CL = 0.48 ± 0.68 respectively, in RPEG. There were 4, 14, and 6% chances 1RMG had a strength advantage of the same magnitude, and 18, 29, and 22% chances, respectively of trivial differences between groups. Conclusions: Both loading-types are effective. However, RPE-based loading may provide a small 1RM strength advantage in a majority of individuals. PMID:29628895

  4. Isolation of Human Skin Dendritic Cell Subsets.

    Science.gov (United States)

    Gunawan, Merry; Jardine, Laura; Haniffa, Muzlifah

    2016-01-01

    Dendritic cells (DCs) are specialized leukocytes with antigen-processing and antigen-presenting functions. DCs can be divided into distinct subsets by anatomical location, phenotype and function. In human, the two most accessible tissues to study leukocytes are peripheral blood and skin. DCs are rare in human peripheral blood (skin covering an average total surface area of 1.8 m(2) has approximately tenfold more DCs than the average 5 L of total blood volume (Wang et al., J Invest Dermatol 134:965-974, 2014). DCs migrate spontaneously from skin explants cultured ex vivo, which provide an easy method of cell isolation (Larsen et al., J Exp Med 172:1483-1493, 1990; Lenz et al., J Clin Invest 92:2587-2596, 1993; Nestle et al., J Immunol 151:6535-6545, 1993). These factors led to the extensive use of skin DCs as the "prototype" migratory DCs in human studies. In this chapter, we detail the protocols to isolate DCs and resident macrophages from human skin. We also provide a multiparameter flow cytometry gating strategy to identify human skin DCs and to distinguish them from macrophages.

  5. Spontaneous correction of anterior crossbite by RPE anchored on deciduous teeth in the early mixed dentition.

    Science.gov (United States)

    Rosa, M; Lucchi, P; Mariani, L; Caprioglio, A

    2012-09-01

    The purpose of this study was to evaluate the effectiveness of Haas RPE anchored on deciduous teeth in the early mixed dentition, for inducing the spontaneous correction of permanent incisor's crossbite, without compliance, without post bite-plane and no involvement of the permanent teeth. The sample group comprised 50 consecutive patients (mean age 8y 5m, SD 2y 1m), 31 males, 19 females. They showed a cross-bite affecting one or more permanent incisors, for a total of 70 teeth. The patients were treated with Haas RPE appliance anchored on second deciduous molars and bonded on deciduous canines. No direct forces were applied on the permanent teeth. Anterior crossbite self-corrected 'spontaneously' in 84% of the cases. Lateral incisors had a higher rate of self-correction than central incisors. All hyper-divergent subjects showed a spontaneous crossbite self-correction. The early maxillary expansion by Haas RPE anchored on deciduous teeth is an efficient and effective procedure to induce the anterior crossbite self-correction in the early mixed dentition without the need of a bite-plane, no involvement of the permanent teeth and without compliance.

  6. Neocortical glial cell numbers in human brains.

    Science.gov (United States)

    Pelvig, D P; Pakkenberg, H; Stark, A K; Pakkenberg, B

    2008-11-01

    Stereological cell counting was applied to post-mortem neocortices of human brains from 31 normal individuals, age 18-93 years, 18 females (average age 65 years, range 18-93) and 13 males (average age 57 years, range 19-87). The cells were differentiated in astrocytes, oligodendrocytes, microglia and neurons and counting were done in each of the four lobes. The study showed that the different subpopulations of glial cells behave differently as a function of age; the number of oligodendrocytes showed a significant 27% decrease over adult life and a strong correlation to the total number of neurons while the total astrocyte number is constant through life; finally males have a 28% higher number of neocortical glial cells and a 19% higher neocortical neuron number than females. The overall total number of neocortical neurons and glial cells was 49.3 billion in females and 65.2 billion in males, a difference of 24% with a high biological variance. These numbers can serve as reference values in quantitative studies of the human neocortex.

  7. The Human Cell Surfaceome of Breast Tumors

    Science.gov (United States)

    da Cunha, Júlia Pinheiro Chagas; Galante, Pedro Alexandre Favoretto; de Souza, Jorge Estefano Santana; Pieprzyk, Martin; Carraro, Dirce Maria; Old, Lloyd J.; Camargo, Anamaria Aranha; de Souza, Sandro José

    2013-01-01

    Introduction. Cell surface proteins are ideal targets for cancer therapy and diagnosis. We have identified a set of more than 3700 genes that code for transmembrane proteins believed to be at human cell surface. Methods. We used a high-throuput qPCR system for the analysis of 573 cell surface protein-coding genes in 12 primary breast tumors, 8 breast cell lines, and 21 normal human tissues including breast. To better understand the role of these genes in breast tumors, we used a series of bioinformatics strategies to integrates different type, of the datasets, such as KEGG, protein-protein interaction databases, ONCOMINE, and data from, literature. Results. We found that at least 77 genes are overexpressed in breast primary tumors while at least 2 of them have also a restricted expression pattern in normal tissues. We found common signaling pathways that may be regulated in breast tumors through the overexpression of these cell surface protein-coding genes. Furthermore, a comparison was made between the genes found in this report and other genes associated with features clinically relevant for breast tumorigenesis. Conclusions. The expression profiling generated in this study, together with an integrative bioinformatics analysis, allowed us to identify putative targets for breast tumors. PMID:24195083

  8. Shape memory of human red blood cells.

    Science.gov (United States)

    Fischer, Thomas M

    2004-05-01

    The human red cell can be deformed by external forces but returns to the biconcave resting shape after removal of the forces. If after such shape excursions the rim is always formed by the same part of the membrane, the cell is said to have a memory of its biconcave shape. If the rim can form anywhere on the membrane, the cell would have no shape memory. The shape memory was probed by an experiment called go-and-stop. Locations on the membrane were marked by spontaneously adhering latex spheres. Shape excursions were induced by shear flow. In virtually all red cells, a shape memory was found. After stop of flow and during the return of the latex spheres to the original location, the red cell shape was biconcave. The return occurred by a tank-tread motion of the membrane. The memory could not be eliminated by deforming the red cells in shear flow up to 4 h at room temperature as well as at 37 degrees C. It is suggested that 1). the characteristic time of stress relaxation is >80 min and 2). red cells in vivo also have a shape memory.

  9. Human somatic cell nuclear transfer and cloning.

    Science.gov (United States)

    2012-10-01

    This document presents arguments that conclude that it is unethical to use somatic cell nuclear transfer (SCNT) for infertility treatment due to concerns about safety; the unknown impact of SCNT on children, families, and society; and the availability of other ethically acceptable means of assisted reproduction. This document replaces the ASRM Ethics Committee report titled, "Human somatic cell nuclear transfer (cloning)," last published in Fertil Steril 2000;74:873-6. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  10. Human induced pluripotent stem cell-derived models to investigate human cytomegalovirus infection in neural cells.

    Directory of Open Access Journals (Sweden)

    Leonardo D'Aiuto

    Full Text Available Human cytomegalovirus (HCMV infection is one of the leading prenatal causes of congenital mental retardation and deformities world-wide. Access to cultured human neuronal lineages, necessary to understand the species specific pathogenic effects of HCMV, has been limited by difficulties in sustaining primary human neuronal cultures. Human induced pluripotent stem (iPS cells now provide an opportunity for such research. We derived iPS cells from human adult fibroblasts and induced neural lineages to investigate their susceptibility to infection with HCMV strain Ad169. Analysis of iPS cells, iPS-derived neural stem cells (NSCs, neural progenitor cells (NPCs and neurons suggests that (i iPS cells are not permissive to HCMV infection, i.e., they do not permit a full viral replication cycle; (ii Neural stem cells have impaired differentiation when infected by HCMV; (iii NPCs are fully permissive for HCMV infection; altered expression of genes related to neural metabolism or neuronal differentiation is also observed; (iv most iPS-derived neurons are not permissive to HCMV infection; and (v infected neurons have impaired calcium influx in response to glutamate.

  11. Dopamine receptor repertoire of human granulosa cells

    Directory of Open Access Journals (Sweden)

    Kunz Lars

    2007-10-01

    Full Text Available Abstract Background High levels of dopamine (DA were described in human ovary and recently evidence for DA receptors in granulosa and luteal cells has been provided, as well. However, neither the full repertoire of ovarian receptors for DA, nor their specific role, is established. Human granulosa cells (GCs derived from women undergoing in vitro fertilization (IVF are an adequate model for endocrine cells of the follicle and the corpus luteum and were therefore employed in an attempt to decipher their DA receptor repertoire and functionality. Methods Cells were obtained from patients undergoing IVF and examined using cDNA-array, RT-PCR, Western blotting and immunocytochemistry. In addition, calcium measurements (with FLUO-4 were employed. Expression of two DA receptors was also examined by in-situ hybridization in rat ovary. Effects of DA on cell viability and cell volume were studied by using an ATP assay and an electronic cell counter system. Results We found members of the two DA receptor families (D1- and D2 -like associated with different signaling pathways in human GCs, namely D1 (as expected and D5 (both are Gs coupled and linked to cAMP increase and D2, D4 (Gi/Gq coupled and linked to IP3/DAG. D3 was not found. The presence of the trophic hormone hCG (10 IU/ml in the culture medium for several days did not alter mRNA (semiquantitative RT-PCR or protein levels (immunocytochemistry/Western blotting of D1,2,4,5 DA receptors. Expression of prototype receptors for the two families, D1 and D2, was furthermore shown in rat granulosa and luteal cells by in situ hybridization. Among the DA receptors found in human GCs, D2 expression was marked both at mRNA and protein levels and it was therefore further studied. Results of additional RT-PCR and Western blots showed two splice variants (D2L, D2S. Irrespective of these variants, D2 proved to be functional, as DA raised intracellular calcium levels. This calcium mobilizing effect of DA was observed

  12. Effects of melatonin and its receptor antagonist on retinal pigment epithelial cells against hydrogen peroxide damage

    Science.gov (United States)

    Rosen, Richard B.; Hu, Dan-Ning; Chen, Min; McCormick, Steven A.; Walsh, Joseph

    2012-01-01

    Purpose Recently, we reported finding that circulating melatonin levels in age-related macular degeneration patients were significantly lower than those in age-matched controls. The purpose of this study was to investigate the hypothesis that melatonin deficiency may play a role in the oxidative damage of the retinal pigment epithelium (RPE) by testing the protective effect of melatonin and its receptor antagonist on RPE cells exposed to H2O2 damage. Methods Cultured human RPE cells were subjected to oxidative stress induced by 0.5 mM H2O2. Cell viability was measured using the microculture tetrazoline test (MTT) assay. Cells were pretreated with or without melatonin for 24 h. Luzindole (50 μM), a melatonin membrane-receptor antagonist, was added to the culture 1 h before melatonin to distinguish direct antioxidant effects from indirect receptor-dependent effects. All tests were performed in triplicate. Results H2O2 at 0.5 mM decreased cell viability to 20% of control levels. Melatonin showed dose-dependent protective effects on RPE cells against H2O2. Cell viability of RPE cells pretreated with 10−10, 10−8, 10−6, and 10−4 M melatonin for 24 h was 130%, 160%, 187%, and 230% of cells treated with H2O2 alone (all p<0.05). Using cells cultured without H2O2 as the control, cell viability of cells treated with H2O2 after pretreatment with 10−10-10−4 M melatonin was still significantly lower than that of the controls, suggesting that melatonin significantly decreased but did not completely abolish the in vitro cytotoxic effects of H2O2. Luzindole completely blocked melatonin’s protective effects at low concentrations of melatonin (10−10-10−8 M) but not at high concentrations (10−6-10−4 M). Conclusions Melatonin has a partial protective effect on RPE cells against H2O2 damage across a wide range of concentrations (10−10-10−4 M). This protective effect occurs through the activation of melatonin membrane receptors at low concentrations (10−10

  13. Some Ethical Concerns About Human Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Zheng, Yue Liang

    2016-10-01

    Human induced pluripotent stem cells can be obtained from somatic cells, and their derivation does not require destruction of embryos, thus avoiding ethical problems arising from the destruction of human embryos. This type of stem cell may provide an important tool for stem cell therapy, but it also results in some ethical concerns. It is likely that abnormal reprogramming occurs in the induction of human induced pluripotent stem cells, and that the stem cells generate tumors in the process of stem cell therapy. Human induced pluripotent stem cells should not be used to clone human beings, to produce human germ cells, nor to make human embryos. Informed consent should be obtained from patients in stem cell therapy.

  14. Cell cycle regulation in human embryonic stem cells: links to adaptation to cell culture.

    Science.gov (United States)

    Barta, Tomas; Dolezalova, Dasa; Holubcova, Zuzana; Hampl, Ales

    2013-03-01

    Cell cycle represents not only a tightly orchestrated mechanism of cell replication and cell division but it also plays an important role in regulation of cell fate decision. Particularly in the context of pluripotent stem cells or multipotent progenitor cells, regulation of cell fate decision is of paramount importance. It has been shown that human embryonic stem cells (hESCs) show unique cell cycle characteristics, such as short doubling time due to abbreviated G1 phase; these properties change with the onset of differentiation. This review summarizes the current understanding of cell cycle regulation in hESCs. We discuss cell cycle properties as well as regulatory machinery governing cell cycle progression of undifferentiated hESCs. Additionally, we provide evidence that long-term culture of hESCs is accompanied by changes in cell cycle properties as well as configuration of several cell cycle regulatory molecules.

  15. RPE and Velocity Relationships for the Back Squat, Bench Press, and Deadlift in Powerlifters.

    Science.gov (United States)

    Helms, Eric R; Storey, Adam; Cross, Matt R; Brown, Scott R; Lenetsky, Seth; Ramsay, Hamish; Dillen, Carolina; Zourdos, Michael C

    2017-02-01

    Helms, ER, Storey, A, Cross, MR, Browm, SR, Lenetsky, S, Ramsay, H, Dillen, C, and Zourdos, MC. RPE and velocity relationships for the back squat, bench press, and deadlift in powerlifters. J Strength Cond Res 31(2): 292-297, 2017-The purpose of this study was to compare average concentric velocity (ACV) and rating of perceived exertion (RPE) based on repetitions in reserve on the squat, bench press, and deadlift. Fifteen powerlifters (3 women and 12 men, mean age 28.4 ± 8.5 years) worked up to a one repetition maximum (1RM) on each lift. Rating of perceived exertion was recorded on all sets, and the ACV was recorded for all sets performed at 80% of estimated 1RM and higher, up to 1RM. Rating of perceived exertion at 1RM on squat, bench press, and deadlift was 9.6 ± 0.5, 9.7 ± 0.4, and 9.6 ± 0.5, respectively and was not significantly different (p > 0.05). The ACV at 1RM on squat, bench press and deadlift was 0.23 ± 0.05, 0.10 ± 0.04, and 0.14 ± 0.05 m·second, respectively. Squat was faster than both bench press and deadlift (p > 0.001), and deadlift was faster than bench press (p = 0.05). Very strong relationships (r = 0.88-0.91) between percentage 1RM and RPE were observed on each lift. The ACV showed strong (r = -0.79 to -0.87) and very strong (r = -0.90 to 92) inverse relationships with RPE and percentage 1RM on each lift, respectively. We conclude that RPE may be a useful tool for prescribing intensity for squat, bench press, and deadlift in powerlifters, in addition to traditional methods such as percentage of 1RM. Despite high correlations between percentage 1RM and ACV, a "velocity load profile" should be developed to prescribe intensity on an individual basis with appropriate accuracy.

  16. Cell Culture Assay for Human Noroviruses [response

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Tim M.; Honer Zu Bentrup, Kerstin; Orosz Coghlan, Patricia; Dohnalkova, Alice; Mayer, Brooke K.; Bartholomew, Rachel A.; Valdez, Catherine O.; Bruckner-Lea, Cindy J.; Gerba, Charles P.; Abbaszadegan, Morteza A.; Nickerson, Cheryl A.

    2007-07-01

    We appreciate the comments provided by Leung et al., in response to our recently published article “In Vitro Cell Culture Infectivity Assay for Human Noroviruses” by Straub et al. (1). The specific aim of our project was to develop an in vitro cell culture infectivity assay for human noroviruses (hNoV) to enhance risk assessments when they are detected in water supplies. Reverse transcription (RT) qualitative or quantitative PCR are the primary assays for waterborne NoV monitoring. However, these assays cannot distinguish between infectious vs. non-infectious virions. When hNoV is detected in water supplies, information provided by our infectivity assay will significantly improve risk assessment models and protect human health, regardless of whether we are propagating NoV. Indeed, in vitro cell culture infectivity assays for the waterborne pathogen Cryptosporidium parvum that supplement approved fluorescent microscopy assays, do not result in amplification of the environmentally resistant hard-walled oocysts (2). However, identification of life cycle stages in cell culture provides evidence of infectious oocysts in a water supply. Nonetheless, Leung et al.’s assertion regarding the suitability of our method for the in vitro propagation of high titers of NoV is valid for the medical research community. In this case, well-characterized challenge pools of virus would be useful for developing and testing diagnostics, therapeutics, and vaccines. As further validation of our published findings, we have now optimized RT quantitative PCR to assess the level of viral production in cell culture, where we are indeed finding significant increases in viral titer. The magnitude and time course of these increases is dependent on both virus strain and multiplicity of infection. We are currently preparing a manuscript that will discuss these findings in greater detail, and the implications this may have for creating viral challenge pools

  17. Nicotinamide extends replicative lifespan of human cells.

    Science.gov (United States)

    Kang, Hyun Tae; Lee, Hyung Il; Hwang, Eun Seong

    2006-10-01

    We found that an ongoing application of nicotinamide to normal human fibroblasts not only attenuated expression of the aging phenotype but also increased their replicative lifespan, causing a greater than 1.6-fold increase in the number of population doublings. Although nicotinamide by itself does not act as an antioxidant, the cells cultured in the presence of nicotinamide exhibited reduced levels of reactive oxygen species (ROS) and oxidative damage products associated with cellular senescence, and a decelerated telomere shortening rate without a detectable increase in telomerase activity. Furthermore, in the treated cells growing beyond the original Hayflick limit, the levels of p53, p21WAF1, and phospho-Rb proteins were similar to those in actively proliferating cells. The nicotinamide treatment caused a decrease in ATP levels, which was stably maintained until the delayed senescence point. Nicotinamide-treated cells also maintained high mitochondrial membrane potential but a lower respiration rate and superoxide anion level. Taken together, in contrast to its demonstrated pro-aging effect in yeast, nicotinamide extends the lifespan of human fibroblasts, possibly through reduction in mitochondrial activity and ROS production.

  18. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins

    Directory of Open Access Journals (Sweden)

    Hayato Fukusumi

    2016-01-01

    Full Text Available Human neural progenitor cells (hNPCs have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi. Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes.

  19. Immortalization of human myogenic progenitor cell clone retaining multipotentiality

    International Nuclear Information System (INIS)

    Hashimoto, Naohiro; Kiyono, Tohru; Wada, Michiko R.; Shimizu, Shirabe; Yasumoto, Shigeru; Inagawa, Masayo

    2006-01-01

    Human myogenic cells have limited ability to proliferate in culture. Although forced expression of telomerase can immortalize some cell types, telomerase alone delays senescence of human primary cultured myogenic cells, but fails to immortalize them. In contrast, constitutive expression of both telomerase and the E7 gene from human papillomavirus type 16 immortalizes primary human myogenic cells. We have established an immortalized primary human myogenic cell line preserving multipotentiality by ectopic expression of telomerase and E7. The immortalized human myogenic cells exhibit the phenotypic characteristics of their primary parent, including an ability to undergo myogenic, osteogenic, and adipogenic terminal differentiation under appropriate culture conditions. The immortalized cells will be useful for both basic and applied studies aimed at human muscle disorders. Furthermore, immortalization by transduction of telomerase and E7 represents a useful method by which to expand human myogenic cells in vitro without compromising their ability to differentiate

  20. Human prostatic cancer cells, PC3, elaborate mitogenic activity which selectively stimulates human bone cells

    International Nuclear Information System (INIS)

    Perkel, V.S.; Mohan, S.; Herring, S.J.; Baylink, D.J.; Linkhart, T.A.

    1990-01-01

    Prostatic cancer typically produces osteoblastic metastases which are not attended by marrow fibrosis. In the present study we sought to test the hypothesis that prostatic cancer cells produce factor(s) which act selectively on human osteoblasts. Such a paracrine mechanism would explain the observed increase in osteoblasts, unaccompanied by an increase in marrow fibroblasts. To test this hypothesis we investigated the mitogenic activity released by the human prostatic tumor cell line, PC3. PC3 cells have been reported previously to produce mitogenic activity for cells that was relatively specific for rat osteoblasts compared to rat fibroblasts. However, the effects of this activity on human cells has not been examined previously. PC3-conditioned medium (CM) (5-50 micrograms CM protein/ml) stimulated human osteoblast proliferation by 200-950% yet did not stimulate human fibroblast proliferation ([3H]thymidine incorporation). PC3 CM also increased cell numbers in human osteoblast but not fibroblast cell cultures. To determine whether the osteoblast-specific mitogenic activity could be attributed to known bone growth factors, specific assays for these growth factors were performed. PC3 CM contained 10 pg insulin-like growth factor (IGF) I, less than 2 pg IGF II, 54 pg basic fibroblast growth factor, and 16 pg transforming growth factor beta/microgram CM protein. None of these growth factors alone or in combination could account for the observed osteoblast-specific PC3 cell-derived mitogenic activity. Furthermore, when 5 micrograms/ml PC3 CM was tested in combination with maximally effective concentrations of either basic fibroblast growth factor, IGF I, IGF II, or transforming growth factor beta, it produced an additive effect suggesting that PC3 CM stimulates osteoblast proliferation by a mechanism independent of these bone mitogens

  1. Differentiation of blood T cells: Reprogramming human induced pluripotent stem cells into neuronal cells

    Directory of Open Access Journals (Sweden)

    Ping-Hsing Tsai

    2015-06-01

    Conclusion: We have developed a safer method to generate integration-free and nonviral human iPSCs from adult somatic cells. This induction method will be useful for the derivation of human integration-free iPSCs and will also be applicable to the generation of iPSCs-derived neuronal cells for drug screening or therapeutics in the near future.

  2. Markers of T Cell Senescence in Humans

    Directory of Open Access Journals (Sweden)

    Weili Xu

    2017-08-01

    Full Text Available Many countries are facing the aging of their population, and many more will face a similar obstacle in the near future, which could be a burden to many healthcare systems. Increased susceptibility to infections, cardiovascular and neurodegenerative disease, cancer as well as reduced efficacy of vaccination are important matters for researchers in the field of aging. As older adults show higher prevalence for a variety of diseases, this also implies higher risk of complications, including nosocomial infections, slower recovery and sequels that may reduce the autonomy and overall quality of life of older adults. The age-related effects on the immune system termed as “immunosenescence” can be exemplified by the reported hypo-responsiveness to influenza vaccination of the elderly. T cells, which belong to the adaptive arm of the immune system, have been extensively studied and the knowledge gathered enables a better understanding of how the immune system may be affected after acute/chronic infections and how this matters in the long run. In this review, we will focus on T cells and discuss the surface and molecular markers that are associated with T cell senescence. We will also look at the implications that senescent T cells could have on human health and diseases. Finally, we will discuss the benefits of having these markers for investigators and the future work that is needed to advance the field of T cell senescence markers.

  3. Human embryonic stem cells and microenvironment

    Directory of Open Access Journals (Sweden)

    Banu İskender

    2014-09-01

    Full Text Available Human embryonic stem cells (hESCs possess a great potential in the field of regenerative medicine by their virtue of pluripotent potential with indefinite proliferation capabilities. They can self renew themselves and differentiate into three embryonic germ layers. Although they are conventionally grown on mitotically inactivated mouse feeder cells, there are in vitro culture systems utilizing feeder cells of human origin in order to prevent cross-species contamination. Recently established in vitro culture systems suggested that direct interaction with feeder cells is not necessary but rather attachment to a substrate is required to ensure long-term, efficient hESC culture in vitro. This substrate is usually composed of a mixture of extracellular matrix components representing in vivo natural niche. In hESC biology, the mechanism of interaction of hESCs with extracellular matrix molecules remained insufficiently explored area of research due to their transient nature of interaction with the in vivo niche. However, an in vitro culture system established using extracellular matrix molecules may provide a safer alternative to culture systems with feeder cells while paving the way to Good Manufacturing Practice-GMP production of hESCs for therapeutic purposes. Therefore, it is essential to study the interaction of extracellular matrix molecules with hESCs in order to standardize in vitro culture systems for large-scale production of hESCs in a less labor-intensive way. This would not only provide valuable information regarding the mechanisms that control pluripotency but also serve to dissect the molecular signaling pathways of directed differentiation for prospective therapeutic applications in the future. J Clin Exp Invest 2014; 5 (3: 486-495

  4. Xanthophylls are preferentially taken up compared with beta-carotene by retinal cells via a SRBI-dependent mechanism.

    Science.gov (United States)

    During, Alexandrine; Doraiswamy, Sundari; Harrison, Earl H

    2008-08-01

    The purpose of this study was to investigate the mechanisms by which carotenoids [xanthophylls vs. beta-carotene(beta-C)] are taken up by retinal pigment epithelial (RPE) cells. The human RPE cell line, ARPE-19, was used. When ARPE-19 cells were fully differentiated (7-9 weeks), the xanthophylls lutein (LUT) and zeaxanthin (ZEA) were taken up by cells to an extent 2-fold higher than beta-C (P xanthophylls versus the carotene by a process that appears to be entirely SR-BI-dependent for ZEA and partly so for beta-C. This mechanism may explain, in part, the preferential accumulation of xanthophylls in the macula of the retina.

  5. Xanthophylls are preferentially taken up compared with β-carotene by retinal cells via a SRBI-dependent mechanism*1

    Science.gov (United States)

    During, Alexandrine; Doraiswamy, Sundari; Harrison, Earl H.

    2008-01-01

    The purpose of this study was to investigate the mechanisms by which carotenoids [xanthophylls vs. β-carotene(β-C)] are taken up by retinal pigment epithelial (RPE) cells. The human RPE cell line, ARPE-19, was used. When ARPE-19 cells were fully differentiated (7–9 weeks), the xanthophylls lutein (LUT) and zeaxanthin (ZEA) were taken up by cells to an extent 2-fold higher than β-C (P xanthophylls versus the carotene by a process that appears to be entirely SR-BI-dependent for ZEA and partly so for β-C. This mechanism may explain, in part, the preferential accumulation of xanthophylls in the macula of the retina. PMID:18424859

  6. The Cultivation of Human Granulosa Cells

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    Lenka Brůčková

    2008-01-01

    Full Text Available The major functions of granulosa cells (GCs include the production of steroids, as well as a myriad of growth factors to interact with the oocyte during its development within the ovarian follicle. Also FSH stimulates GCs to convert androgens (coming from the thecal cells to estradiol by aromatase. However, after ovulation the GCs produce progesterone that may maintain a potential pregnancy. Experiments with human GCs are mainly focused on the purification of GCs from ovarian follicular fluid followed by FACS analysis or short-term cultivation. The aim of our study was to cultivate GCs for a long period, to characterize their morphology and phenotype. Moreover, we have cultivated GCs under gonadotropin stimulation in order to simulate different pathological mechanisms during folliculogenesis (e.g. ovarian hyperstimulation syndrome. GCs were harvested from women undergoing in vitro fertilization. Complex oocyte-cumulus oophorus was dissociated by hyaluronidase. The best condition for transport of GCs was optimized as short transport in follicular fluid at 37 °C. GCs expansion medium consisted of DMEM/F12, 2 % FCS, ascorbic acid, dexamethasone, L-glutamine, gentamycine, penicillin, streptomycin and growth factors (EGF, bFGF. GCs transported in follicular fluid and cultivated in 2 % FCS containing DMEM/F12 medium supplemented with follicular fluid presented increased adhesion, proliferation, viability and decreased doubling time. Cell viability was 92 % and mean cell doubling time was 52 hrs. We have optimized transport and cultivation protocols for long-term cultivation of GCs.

  7. Single Cell Dissection of Human Pancreatic Islet Dysfunction in Diabetes

    Science.gov (United States)

    2017-06-01

    of memory T cells , innate cells and the differentiation potential of naive T cells during ME/CFS; and 3) To determine the T cell and innate cell ...apoptosis and the innate immune response in human pancreatic β- cells . Diabetes 64: 3808–3817. Marselli L, Thorne J, Dahiya S, Sgroi DC, Sharma A, Bonner-Weir...interactive nature of CellView aids in cell doublet identification. In the PBMC data, ‘Subcluster-analysis’ reveals a mixture of lymphoid and myeloid

  8. RPE y velocidad como marcadores de intensidad en el press de banca

    OpenAIRE

    Bautista, I. J.; Chirosa, I. J.; Chirosa, L. J.; Martín, I.; Revilla, J.

    2016-01-01

    El propósito de esta investigación fue analizar la relación entre la evolución de la velocidad media (Velmedia) y los valores de la escala OMNI-RES, en 3 intensidades (carga Inicial [CI], máxima potencia [MP] y repetición máxima [RM]). 38 sujetos divididos en dos grupos: Entrenados (G1, n = 19) y No Entrenados (G2, n = 19) realizaron un test incremental de cargas en el ejercicio del press de banca. En la percepción subjetiva del esfuerzo (RPE) no se encontraron diferencias significativas entr...

  9. RPE vs. Percentage 1RM Loading in Periodized Programs Matched for Sets and Repetitions

    Directory of Open Access Journals (Sweden)

    Eric R. Helms

    2018-03-01

    Full Text Available Purpose: To investigate differences between rating of perceived exertion (RPE and percentage one-repetition maximum (1RM load assignment in resistance-trained males (19–35 years performing protocols with matched sets and repetitions differentiated by load-assignment.Methods: Participants performed squats then bench press 3x/weeks in a daily undulating format over 8-weeks. Participants were counterbalanced by pre-test 1RM then assigned to percentage 1RM (1RMG, n = 11; load-assignment via percentage 1RMs, or RPE groups (RPEG, n = 10; participant-selected loads to reach target RPE ranges. Ultrasonography determined pre and post-test pectoralis (PMT, and vastus lateralis muscle thickness at 50 (VLMT50 and 70% (VLMT70 femur-length.Results: Bench press (1RMG +9.64 ± 5.36; RPEG + 10.70 ± 3.30 kg, squat (1RMG + 13.91 ± 5.89; RPEG + 17.05 ± 5.44 kg and their combined-total 1RMs (1RMG + 23.55 ± 10.38; RPEG + 27.75 ± 7.94 kg increased (p < 0.05 in both groups as did PMT (1RMG + 1.59 ± 1.33; RPEG +1.90 ± 1.91 mm, VLMT50 (1RMG +2.13 ± 1.95; RPEG + 1.85 ± 1.97 mm and VLMT70 (1RMG + 2.40 ± 2.22; RPEG + 2.31 ± 2.27 mm. Between-group differences were non-significant (p > 0.05. Magnitude-based inferences revealed 79, 57, and 72% chances of mean small effect size (ES advantages for squat; ES 90% confidence limits (CL = 0.50 ± 0.63, bench press; ES 90% CL = 0.28 ± 0.73, and combined-total; ES 90% CL = 0.48 ± 0.68 respectively, in RPEG. There were 4, 14, and 6% chances 1RMG had a strength advantage of the same magnitude, and 18, 29, and 22% chances, respectively of trivial differences between groups.Conclusions: Both loading-types are effective. However, RPE-based loading may provide a small 1RM strength advantage in a majority of individuals.

  10. Proteomic Analysis of Human Blastocoel Fluid and Blastocyst Cells

    DEFF Research Database (Denmark)

    Linnert Jensen, Pernille; Beck, Hans Christian; Petersen, Jørgen

    The human blastocyst consists of 100-200 cells that are organized in an outer layer of differentiated trophectoderm (TE) cells lining the blastocyst cavity into which the undifferentiated inner cell mass (ICM) protrudes. The cavity of the blastocyst is filled with blastocoel fluid to which all...... the cells of the blastocyst are exposed. The ICM is the starting point for the development of undifferentiated human embryonic stem cells (hESCs), which posses the potential to develop into any cell type present in the adult human body [1,2]. This ability makes hESCs a potential source of cells...

  11. Cytoplasmic and nuclear anti-apoptotic roles of αB-crystallin in retinal pigment epithelial cells.

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    Woo Jin Jeong

    Full Text Available In addition to its well-characterized role in the lens, αB-crystallin performs other functions. Methylglyoxal (MGO can alter the function of the basement membrane of retinal pigment epithelial (RPE cells. Thus, if MGO is not efficiently detoxified, it can induce adverse reactions in RPE cells. In this study, we examined the mechanisms underlying the anti-apoptotic activity of αB-crystallin in the human retinal pigment epithelial cell line ARPE-19 following MGO treatment using various assays, including nuclear staining, flow cytometry, DNA electrophoresis, pulse field gel electrophoresis, western blot analysis, confocal microscopy and co-immunoprecipitation assays. To directly assess the role of phosphorylation of αB-crystallin, we used site-directed mutagenesis to convert relevant serine residues to alanine residues. Using these techniques, we demonstrated that MGO induces apoptosis in ARPE-19 cells. Silencing αB-crystallin sensitized ARPE-19 cells to MGO-induced apoptosis, indicating that αB-crystallin protects ARPE-19 cells from MGO-induced apoptosis. Furthermore, we found that αB-crystallin interacts with the caspase subtypes, caspase-2L, -2S, -3, -4, -7, -8, -9 and -12 in untreated control ARPE-19 cells and that MGO treatment caused the dissociation of these caspase subtypes from αB-crystallin; transfection of S19A, S45A or S59A mutants caused the depletion of αB-crystallin from the nuclei of untreated control RPE cells leading to the release of caspase subtypes. Additionally, transfection of these mutants enhanced MGO-induced apoptosis in ARPE-19 cells, indicating that phosphorylation of nuclear αB-crystallin on serine residues 19, 45 and 59 plays a pivotal role in preventing apoptosis in ARPE-19 cells. Taken together, these results suggest that αB-crystallin prevents caspase activation by physically interacting with caspase subtypes in the cytoplasm and nucleus, thereby protecting RPE cells from MGO-induced apoptosis.

  12. Studies in human skin epithelial cell carcinogenesis

    International Nuclear Information System (INIS)

    Lehman, T.A.

    1987-01-01

    Metabolism and DNA adduct formation of benzo[a]pyrene (BP) by human epidermal keratinocytes pretreated with inhibitors or inducer of cytochrame P450 was studied. To study DNA adduct analysis, cultures were pretreated as described above, and then treated with non-radiolabeled BP. DNA was prepared from these cultures, digested to the nucleotide level, and 32 P-postlabeled for adduct analysis. Cultures pretreated with BHA, 7,8-BF or disulfiralm formed significantly fewer BPDE I-dB adducts than non-pretreated cultures, while cultures pretreated with MeBHA formed more BPDE-I-dG adducts. MeBHA increased BP activation and adduct formation inhuman keratinocyte in cultures by inducing a specific isoenzyme of cytochrome P450 which preferentially increases the oxidative metabolism of BP to 7,8 diol BP and 7,8 diol BP to BPDE I. To approximate an in vivo human system, metabolism of BPDE I by human skin xenografts treated with cell cycles modulators was studied. When treated with BPDE I, specific carcinogen-DNA adducts were formed. Separation and identification of these adducts by the 32 P-postlabeling technique indicated that the 7R- and 7S-BPDE I-dG adducts were the major adducts

  13. Assessment of Safety and Functional Efficacy of Stem Cell-Based Therapeutic Approaches Using Retinal Degenerative Animal Models

    Directory of Open Access Journals (Sweden)

    Tai-Chi Lin

    2017-01-01

    Full Text Available Dysfunction and death of retinal pigment epithelium (RPE and or photoreceptors can lead to irreversible vision loss. The eye represents an ideal microenvironment for stem cell-based therapy. It is considered an “immune privileged” site, and the number of cells needed for therapy is relatively low for the area of focused vision (macula. Further, surgical placement of stem cell-derived grafts (RPE, retinal progenitors, and photoreceptor precursors into the vitreous cavity or subretinal space has been well established. For preclinical tests, assessments of stem cell-derived graft survival and functionality are conducted in animal models by various noninvasive approaches and imaging modalities. In vivo experiments conducted in animal models based on replacing photoreceptors and/or RPE cells have shown survival and functionality of the transplanted cells, rescue of the host retina, and improvement of visual function. Based on the positive results obtained from these animal experiments, human clinical trials are being initiated. Despite such progress in stem cell research, ethical, regulatory, safety, and technical difficulties still remain a challenge for the transformation of this technique into a standard clinical approach. In this review, the current status of preclinical safety and efficacy studies for retinal cell replacement therapies conducted in animal models will be discussed.

  14. Technical Challenges in the Derivation of Human Pluripotent Cells

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    Parinya Noisa

    2011-01-01

    Full Text Available It has long been discovered that human pluripotent cells could be isolated from the blastocyst state of embryos and called human embryonic stem cells (ESCs. These cells can be adapted and propagated indefinitely in culture in an undifferentiated manner as well as differentiated into cell representing the three major germ layers: endoderm, mesoderm, and ectoderm. However, the derivation of human pluripotent cells from donated embryos is limited and restricted by ethical concerns. Therefore, various approaches have been explored and proved their success. Human pluripotent cells can also be derived experimentally by the nuclear reprogramming of somatic cells. These techniques include somatic cell nuclear transfer (SCNT, cell fusion and overexpression of pluripotent genes. In this paper, we discuss the technical challenges of these approaches for nuclear reprogramming, involving their advantages and limitations. We will also highlight the possible applications of these techniques in the study of stem cell biology.

  15. Stereological quantification of mast cells in human synovium

    DEFF Research Database (Denmark)

    Damsgaard, T E; Sørensen, Flemming Brandt; Herlin, T

    1999-01-01

    Mast cells participate in both the acute allergic reaction as well as in chronic inflammatory diseases. Earlier studies have revealed divergent results regarding the quantification of mast cells in the human synovium. The aim of the present study was therefore to quantify these cells in the human...... synovium, using stereological techniques. Different methods of staining and quantification have previously been used for mast cell quantification in human synovium. Stereological techniques provide precise and unbiased information on the number of cell profiles in two-dimensional tissue sections of......, in this case, human synovium. In 10 patients suffering from osteoarthritis a median of 3.6 mast cells/mm2 synovial membrane was found. The total number of cells (synoviocytes, fibroblasts, lymphocytes, leukocytes) present was 395.9 cells/mm2 (median). The mast cells constituted 0.8% of all the cell profiles...

  16. A Chemical Probe that Labels Human Pluripotent Stem Cells

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    Nao Hirata

    2014-03-01

    Full Text Available A small-molecule fluorescent probe specific for human pluripotent stem cells would serve as a useful tool for basic cell biology research and stem cell therapy. Screening of fluorescent chemical libraries with human induced pluripotent stem cells (iPSCs and subsequent evaluation of hit molecules identified a fluorescent compound (Kyoto probe 1 [KP-1] that selectively labels human pluripotent stem cells. Our analyses indicated that the selectivity results primarily from a distinct expression pattern of ABC transporters in human pluripotent stem cells and from the transporter selectivity of KP-1. Expression of ABCB1 (MDR1 and ABCG2 (BCRP, both of which cause the efflux of KP-1, is repressed in human pluripotent stem cells. Although KP-1, like other pluripotent markers, is not absolutely specific for pluripotent stem cells, the identified chemical probe may be used in conjunction with other reagents.

  17. Alternative Sources of Adult Stem Cells: Human Amniotic Membrane

    Science.gov (United States)

    Wolbank, Susanne; van Griensven, Martijn; Grillari-Voglauer, Regina; Peterbauer-Scherb, Anja

    Human amniotic membrane is a highly promising cell source for tissue engineering. The cells thereof, human amniotic epithelial cells (hAEC) and human amniotic mesenchymal stromal cells (hAMSC), may be immunoprivileged, they represent an early developmental status, and their application is ethically uncontroversial. Cell banking strategies may use freshly isolated cells or involve in vitro expansion to increase cell numbers. Therefore, we have thoroughly characterized the effect of in vitro cultivation on both phenotype and differentiation potential of hAEC. Moreover, we present different strategies to improve expansion including replacement of animal-derived supplements by human platelet products or the introduction of the catalytic subunit of human telomerase to extend the in vitro lifespan of amniotic cells. Characterization of the resulting cultures includes phenotype, growth characteristics, and differentiation potential, as well as immunogenic and immunomodulatory properties.

  18. In Vitro Cardiomyogenic Potential of Human Amniotic Fluid Stem Cells

    OpenAIRE

    Guan, Xuan; Delo, Dawn M.; Atala, Anthony; Soker, Shay

    2011-01-01

    Stem cell therapy for damaged cardiac tissue is currently limited by a number of factors, including the inability to obtain sufficient cell numbers, the potential tumorigenicity of certain types of stem cells, and the possible link between stem cell therapy and the development of malignant arrhythmias. In this study, we investigated whether human amniotic fluid-derived stem (hAFS) cells could be a potential source of cells for cardiac cell therapy by testing the in vitro differentiation capab...

  19. Trichloroethylene toxicity in a human hepatoma cell line

    Energy Technology Data Exchange (ETDEWEB)

    Thevenin, E.; McMillian, J. [Medical Univ. of Charleston South Carolina, SC (United States)

    1994-12-31

    The experiments conducted in this study were designed to determine the usefullness of hepatocyte cultures and a human hepatoma cell line as model systems for assessing human susceptibility to hepatocellular carcinoma due to exposure to trichloroethylene. The results from these studies will then be analyzed to determine if human cell lines can be used to conduct future experiments of this nature.

  20. Identification of human tissue cross-presenting dendritic cells

    OpenAIRE

    Haniffa, Muzlifah; Collin, Matthew; Ginhoux, Florent

    2013-01-01

    Dendritic cells (DCs) are a heterogeneous group of functionally specialized antigen-presenting cells. We recently characterized the human tissue cross-presenting DCs and aligned the human and mouse DC subsets. Our findings will facilitate the translation of murine DC studies to the human setting and aid the design of DC-based vaccine strategies for infection and cancer immunotherapy.

  1. Alanine/RPE dosimetry in the process of blood irradiation; Dosimetria alanina/RPE en el proceso de irradiacion de sangre

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F.; Covas, D.T.; Baffa, O. [Departamento de Fisica e Matematica, FFCLRP, Universidade de Sao Paulo, 14040-901 Ribeirao Preto-SP (Brazil)

    2000-07-01

    A set of eighty dosemeters approximately of Dl- alanine was proportioned to the Hemo center of Hospital das Clinicas of Medicine Faculty at Ribeirao Preto (HC-FRMP) in the Sao Paulo University, with the purpose to realize a quality control of the radiation dose supplied to blood bags. These dosemeters were divided in eight groups and irradiated for a two months period.The dosemeters were adhered to the bags and arranged inside of an acrylic box filled water with dimensions: (40x40x20) cm{sup 3}. The box irradiation was made using two fields parallel-opposed of (40x40) cm{sup 2} at 80 cm distance source-surface, in the Radiotherapy Service of HC-FMRP, with a {sup 60} Co teletherapy unit. The irradiation time was sufficient to supply a dose of 20 Gy approximately in the box center. The RPE measures were realized in a Varian E-4 spectrometer operating in X-band. For the total of dosemeters and for the irradiation volume, the minimum and maximum doses were of 14 Gy and 23 Gy respectively. The mean dose was (18{+-}2) Gy (1 {sigma}), and the variability coefficient 11 %. Around 5 % of the bags received a dose under of the recommended limit by the Brazilian legislation and as consequence, the exposure time was increased. (Author)

  2. Enhanced casein kinase II activity in human tumour cell cultures

    DEFF Research Database (Denmark)

    Prowald, K; Fischer, H; Issinger, O G

    1984-01-01

    Casein kinase II (CKII) activity is enhanced as much as 2-3 fold in established and 4-5-fold in transformed human cell lines when compared to that of fibroblasts and primary human tumour cell cultures where CKII activity never exceeded a basic level. The high activity of CKII in transformed cells...

  3. MODERATE CYTOTOXICITY OF PROANTHOCYANIDINS TO HUMAN TUMOR-CELL LINES

    NARCIS (Netherlands)

    KOLODZIEJ, H; HABERLAND, C; WOERDENBAG, HJ; KONINGS, AWT

    In the present study the cytotoxicity of 16 proanthocyanidins was evaluated in GLC(4), a human small cell lung carcinoma cell line, and in COLO 320, a human colorectal cancer cell line, using the microculture tetrazolium (MTT) assay. With IC50 values ranging from 18 to >200 mu m following continuous

  4. Isolation and in vitro expansion of human colonic stem cells

    NARCIS (Netherlands)

    Jung, P.; Sato, T.; Merlos-Suarez, A.; Barriga, F.M.; Iglesias, M.; Rossell, D.; Auer, H.; Gallardo, M.; Blasco, M.A.; Sancho, E.; Clevers, H.; Batlle, E.

    2011-01-01

    Here we describe the isolation of stem cells of the human colonic epithelium. Differential cell surface abundance of ephrin type-B receptor 2 (EPHB2) allows the purification of different cell types from human colon mucosa biopsies. The highest EPHB2 surface levels correspond to epithelial colonic

  5. Personalized Medicine: Cell and Gene Therapy Based on Patient-Specific iPSC-Derived Retinal Pigment Epithelium Cells.

    Science.gov (United States)

    Li, Yao; Chan, Lawrence; Nguyen, Huy V; Tsang, Stephen H

    2016-01-01

    Interest in generating human induced pluripotent stem (iPS) cells for stem cell modeling of diseases has overtaken that of patient-specific human embryonic stem cells due to the ethical, technical, and political concerns associated with the latter. In ophthalmology, researchers are currently using iPS cells to explore various applications, including: (1) modeling of retinal diseases using patient-specific iPS cells; (2) autologous transplantation of differentiated retinal cells that undergo gene correction at the iPS cell stage via gene editing tools (e.g., CRISPR/Cas9, TALENs and ZFNs); and (3) autologous transplantation of patient-specific iPS-derived retinal cells treated with gene therapy. In this review, we will discuss the uses of patient-specific iPS cells for differentiating into retinal pigment epithelium (RPE) cells, uncovering disease pathophysiology, and developing new treatments such as gene therapy and cell replacement therapy via autologous transplantation.

  6. The development of human mast cells. An historical reappraisal

    International Nuclear Information System (INIS)

    Ribatti, Domenico

    2016-01-01

    The understanding of mast cell (MC) differentiation is derived mainly from in vitro studies of different stages of stem and progenitor cells. The hematopoietic lineage development of human MCs is unique compared to other myeloid-derived cells. Human MCs originate from CD34"+/CD117"+/CD13"+multipotent hematopoietic progenitors, which undergo transendothelial recruitment into peripheral tissues, where they complete differentiation. Stem cell factor (SCF) is a major chemotactic factor for MCs and their progenitors. SCF also elicits cell-cell and cell-substratum adhesion, facilitates the proliferation, and sustains the survival, differentiation, and maturation, of MCs. Because MC maturation is influenced by local microenvironmental factors, different MC phenotypes can develop in different tissues and organs. - Highlights: • Human mast cells originate from CD34/CD117/CD13 positive multipotent hematopoietic progenitors. • Stem cell factor is a major chemotactic factor for mast cells and their progenitors. • Different mast cell phenotypes can develop in different tissues and organs.

  7. The Use of Session RPE to Monitor the Intensity of Weight Training in Older Women: Acute Responses to Eccentric, Concentric, and Dynamic Exercises

    Directory of Open Access Journals (Sweden)

    Sandro S. Ferreira

    2014-01-01

    Full Text Available The rating of perceived exertion (RPE is ability to detect and interpret organic sensations while performing exercises. This method has been used to measure the level of effort that is felt during weight-training at a given intensity. The purpose of this investigation was to compare session RPE values with those of traditional RPE measurements for different weight-training muscle actions, performed together or separately. Fourteen women with no former weight-training experience were recruited for the investigation. All participants completed five sessions of exercise: familiarization, maximum force, concentric-only (CONC-only, eccentric-only (ECC-only, and dynamic (DYN = CONC + ECC. The traditional RPE method was measured after each series of exercises, and the session RPE was measured 30 min after the end of the training session. The statistical analyses used were the paired t-test, one-way analysis of variance, and repeated measures analysis of variance. Significant differences between traditional RPE and session RPE for DYN, CONC, and ECC exercises were not found. This investigation demonstrated that session RPE is similar to traditional RPE in terms of weight-training involving concentric, eccentric, or dynamic muscle exercises, and that it can be used to prescribe and monitor weight-training sessions in older subjects.

  8. The commitment of human cells to senescence.

    Science.gov (United States)

    Holliday, Robin

    2014-01-01

    Fifty years ago, it was demonstrated by Leonard Hayflick that human diploid fibroblasts grown in culture have a finite lifespan. Since that time, innumerable experiments have been published to discover the mechanism(s) that are responsible for this 'Hayflick limit' to continuous growth. Much new information has been gained, but there are certain features of this experimental system which have not been fully understood. One is the fact that different populations of the foetal lung strains WI-38 and MRC-5 have a range in division potential of at least a millionfold. The commitment theory of cellular aging, published more than 30 years ago, is able to explain this, but it has been consistently ignored. The theory predicts that bottlenecks, which are transient reductions in population size, can significantly reduce lifespan, or increase variability of lifespans. Computer simulations specify the effects of bottlenecks on longevity, and these were confirmed in two series of experiments. Commitment to senescence may be the loss of telomerase, which leads to the erosion of telomeres and the inability to grow indefinitely. Many experiments have been done with skin fibroblasts from human donors of different age, and it was originally thought that in vitro lifespan was inversely correlated with donor age. In these experiments, a single skin biopsy produces a population of cells that are grown to senescence. However, there is no reason to believe that skin fibroblasts are less variable in their in vitro lifespan than foetal lung strains, in which case the data points with skin cells are so variable that they may completely obscure any inverse correlation between culture lifespans and donor age.

  9. Human Stem Cell Derived Cardiomyocytes: An Alternative ...

    Science.gov (United States)

    Chemical spills and associated deaths in the US has increased 2.6-fold and 16-fold from 1983 to 2012, respectfully. In addition, the number of chemicals to which humans are exposed to in the environment has increased almost 10-fold from 2001 to 2013 within the US. Internationally, a WHO report on the global composite impact of chemicals on health reported that 16% of the total burden of cardiovascular disease was attributed to environmental chemical exposure with 2.5 million deaths per year. Clearly, the cardiovascular system, at all its various developmental and life stages, represents a critical target organ system that can be adversely affected by existing and emerging chemicals (e.g., engineered nanomaterials) in a variety of environmental media. The ability to assess chemical cardiac risk and safety is critically needed but extremely challenging due to the number and categories of chemicals in commerce, as indicated. This presentation\\session will evaluate the use of adult human stem cell derived cardiomyocytes, and existing platforms, as an alternative model to evaluate environmental chemical cardiac toxicity as well as provide key information for the development of predictive adverse outcomes pathways associated with environmental chemical exposures. (This abstract does not represent EPA policy) Rapid and translatable chemical safety screening models for cardiotoxicity current status for informing regulatory decisions, a workshop sponsored by the Society

  10. Efficient and Fast Differentiation of Human Neural Stem Cells from Human Embryonic Stem Cells for Cell Therapy

    Directory of Open Access Journals (Sweden)

    Xinxin Han

    2017-01-01

    Full Text Available Stem cell-based therapies have been used for repairing damaged brain tissue and helping functional recovery after brain injury. Aberrance neurogenesis is related with brain injury, and multipotential neural stem cells from human embryonic stem (hES cells provide a great promise for cell replacement therapies. Optimized protocols for neural differentiation are necessary to produce functional human neural stem cells (hNSCs for cell therapy. However, the qualified procedure is scarce and detailed features of hNSCs originated from hES cells are still unclear. In this study, we developed a method to obtain hNSCs from hES cells, by which we could harvest abundant hNSCs in a relatively short time. Then, we examined the expression of pluripotent and multipotent marker genes through immunostaining and confirmed differentiation potential of the differentiated hNSCs. Furthermore, we analyzed the mitotic activity of these hNSCs. In this report, we provided comprehensive features of hNSCs and delivered the knowledge about how to obtain more high-quality hNSCs from hES cells which may help to accelerate the NSC-based therapies in brain injury treatment.

  11. Bone Marrow–Derived Cells Home to and Regenerate Retinal Pigment Epithelium after Injury

    Science.gov (United States)

    Harris, Jeffrey R.; Brown, Gary A. J.; Jorgensen, Marda; Kaushal, Shalesh; Ellis, E. Ann; Grant, Maria B.; Scott, Edward W.

    2013-01-01

    Purpose To determine whether hematopoietic stem and progenitor cells (HSCs/HPCs) can home to and regenerate the retinal pigment epithelium (RPE) after induced injury. Methods Enriched HSCs/HPCs from green fluorescent protein (gfp) transgenic mice were transplanted into irradiated recipient mice to track bone marrow–derived cells. Physical damage was induced by breaching Bruch’s membrane and inducing vascular endothelial growth factor A (VEGFa) expression to promote neovascularization. RPE damage was also induced by sodium iodate injection (40 mg/kg) into wild-type or albino C57Bl/6 mice. Cell morphology, gfp expression, the presence of the Y chromosome, and the presence of melanosomes were used to determine whether the injured RPE was being repaired by the donor bone marrow. Results Injury to the RPE recruits HSC/HPC–derived cells to incorporate into the RPE layer and differentiate into an RPE phenotype. A portion of the HSCs/HPCs adopt RPE morphology, express melanosomes, and integrate into the RPE without cell fusion. Conclusions HSCs/HPCs can migrate to the RPE layer after physical or chemical injury and regenerate a portion of the damaged cell layer. PMID:16639022

  12. New frontiers in human cell biology and medicine: can pluripotent stem cells deliver?

    Science.gov (United States)

    Goldstein, Lawrence S B

    2012-11-12

    Human pluripotent stem cells provide enormous opportunities to treat disease using cell therapy. But human stem cells can also drive biomedical and cell biological discoveries in a human model system, which can be directly linked to understanding disease or developing new therapies. Finally, rigorous scientific studies of these cells can and should inform the many science and medical policy issues that confront the translation of these technologies to medicine. In this paper, I discuss these issues using amyotrophic lateral sclerosis as an example.

  13. Effects of Human Umbilical Cord Mesenchymal Stem Cells on Human Trophoblast Cell Functions In Vitro

    Directory of Open Access Journals (Sweden)

    Yajing Huang

    2016-01-01

    Full Text Available Trophoblast cell dysfunction is involved in many disorders during pregnancy such as preeclampsia and intrauterine growth restriction. Few treatments exist, however, that target improving trophoblast cell function. Human umbilical cord mesenchymal stem cells (hUCMSCs are capable of self-renewing, can undergo multilineage differentiation, and have homing abilities; in addition, they have immunomodulatory effects and paracrine properties and thus are a prospective source for cell therapy. To identify whether hUCMSCs can regulate trophoblast cell functions, we treated trophoblast cells with hUCMSC supernatant or cocultured them with hUCMSCs. Both treatments remarkably enhanced the migration and invasion abilities of trophoblast cells and upregulated their proliferation ability. At a certain concentration, hUCMSCs also modulated hCG, PIGF, and sEndoglin levels in the trophoblast culture medium. Thus, hUCMSCs have a positive effect on trophoblast cellular functions, which may provide a new avenue for treatment of placenta-related diseases during pregnancy.

  14. CD56 marks human dendritic cell subsets with cytotoxic potential

    NARCIS (Netherlands)

    Roothans, D.; Smits, E.; Lion, E.; Tel, J.; Anguille, S.

    2013-01-01

    Human plasmacytoid and myeloid dendritic cells (DCs), when appropriately stimulated, can express the archetypal natural killer (NK)-cell surface marker CD56. In addition to classical DC functions, CD56(+) DCs are endowed with an unconventional cytotoxic capacity.

  15. Bacteria, fungi, and viruses outnumber human cells 10:1

    Indian Academy of Sciences (India)

    Karen Nelson

    Fig 2. The distribution of the number of human cells by cell type. Sender R ... Type 2 diabetes ... Development of new predictive biomarkers so that preventive ... Microbiome, irrespective of lifestyle and age, which is distinct from races and.

  16. Graphene Oxide–Silver Nanocomposite Enhances Cytotoxic and Apoptotic Potential of Salinomycin in Human Ovarian Cancer Stem Cells (OvCSCs: A Novel Approach for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Yun-Jung Choi

    2018-03-01

    Full Text Available The use of graphene to target and eliminate cancer stem cells (CSCs is an alternative approach to conventional chemotherapy. We show the biomolecule-mediated synthesis of reduced graphene oxide–silver nanoparticle nanocomposites (rGO–Ag using R-phycoerythrin (RPE; the resulting RPE–rGO–Ag was evaluated in human ovarian cancer cells and ovarian cancer stem cells (OvCSCs. The synthesized RPE–rGO–Ag nanocomposite (referred to as rGO–Ag was characterized using various analytical techniques. rGO–Ag showed significant toxicity towards both ovarian cancer cells and OvCSCs. After 3 weeks of incubating OvCSCs with rGO–Ag, the number of A2780 and ALDH+CD133+ colonies was significantly reduced. rGO–Ag was toxic to OvCSCs and reduced cell viability by mediating the generation of reactive oxygen species, leakage of lactate dehydrogenase, reduced mitochondrial membrane potential, and enhanced expression of apoptotic genes, leading to mitochondrial dysfunction and possibly triggering apoptosis. rGO–Ag showed significant cytotoxic potential towards highly tumorigenic ALDH+CD133+ cells. The combination of rGO–Ag and salinomycin induced 5-fold higher levels of apoptosis than each treatment alone. A combination of rGO–Ag and salinomycin at very low concentrations may be suitable for selectively killing OvCSCs and sensitizing tumor cells. rGO–Ag may be a novel nano-therapeutic molecule for specific targeting of highly tumorigenic ALDH+CD133+ cells and eliminating CSCs. This study highlights the potential for targeted therapy of tumor-initiating cells.

  17. Microspectroscopy of spectral biomarkers associated with human corneal stem cells

    OpenAIRE

    Nakamura, Takahiro; Kelly, Jemma G.; Trevisan, J?lio; Cooper, Leanne J.; Bentley, Adam J.; Carmichael, Paul L.; Scott, Andrew D.; Cotte, Marine; Susini, Jean; Martin-Hirsch, Pierre L.; Kinoshita, Shigeru; Fullwood, Nigel J.; Martin, Francis L.

    2010-01-01

    Purpose Synchrotron-based radiation (SRS) Fourier-transform infrared (FTIR) microspectroscopy potentially provides novel biomarkers of the cell differentiation process. Because such imaging gives a ?biochemical-cell fingerprint? through a cell-sized aperture, we set out to determine whether distinguishing chemical entities associated with putative stem cells (SCs), transit-amplifying (TA) cells, or terminally-differentiated (TD) cells could be identified in human corneal epithelium. Methods D...

  18. Intestinal Stem Cell Dynamics: A Story of Mice and Humans.

    Science.gov (United States)

    Hodder, Michael C; Flanagan, Dustin J; Sansom, Owen J

    2018-06-01

    Stem cell dynamics define the probability of accumulating mutations within the intestinal epithelium. In this issue of Cell Stem Cell, Nicholson et al. (2018) report that human intestinal stem cell dynamics differ significantly from those of mice and establish that oncogenic mutations are more likely to expand; therefore, "normal" epithelium may carry multiple mutations. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Comparative mutagenesis of human cells in vivo and in vitro

    International Nuclear Information System (INIS)

    Thilly, W.G.

    1992-05-01

    This report discusses measuring methods of point mutations; high density cell cultures for low dose studies; measurement and sequence determination of mutations in DNA; the mutational spectra of styrene oxide and ethlyene oxide in TK-6 cells; mutational spectrum of Cr in human lymphoblast cells; mutational spectra of radon in TK-6 cells; and the mutational spectra of smokeless tobacco

  20. Characterizing the radioresponse of pluripotent and multipotent human stem cells.

    Directory of Open Access Journals (Sweden)

    Mary L Lan

    Full Text Available The potential capability of stem cells to restore functionality to diseased or aged tissues has prompted a surge of research, but much work remains to elucidate the response of these cells to genotoxic agents. To more fully understand the impact of irradiation on different stem cell types, the present study has analyzed the radioresponse of human pluripotent and multipotent stem cells. Human embryonic stem (ES cells, human induced pluripotent (iPS cells, and iPS-derived human neural stem cells (iPS-hNSCs cells were irradiated and analyzed for cell survival parameters, differentiation, DNA damage and repair and oxidative stress at various times after exposure. While irradiation led to dose-dependent reductions in survival, the fraction of surviving cells exhibited dose-dependent increases in metabolic activity. Irradiation did not preclude germ layer commitment of ES cells, but did promote neuronal differentiation. ES cells subjected to irradiation exhibited early apoptosis and inhibition of cell cycle progression, but otherwise showed normal repair of DNA double-strand breaks. Cells surviving irradiation also showed acute and persistent increases in reactive oxygen and nitrogen species that were significant at nearly all post-irradiation times analyzed. We suggest that stem cells alter their redox homeostasis to adapt to adverse conditions and that radiation-induced oxidative stress plays a role in regulating the function and fate of stem cells within tissues compromised by radiation injury.

  1. Sequential cancer mutations in cultured human intestinal stem cells

    NARCIS (Netherlands)

    Drost, Jarno; van Jaarsveld, Richard H.; Ponsioen, Bas; Zimberlin, Cheryl; van Boxtel, Ruben; Buijs, Arjan; Sachs, Norman; Overmeer, René M.; Offerhaus, G. Johan; Begthel, Harry; Korving, Jeroen; van de Wetering, Marc; Schwank, Gerald; Logtenberg, Meike; Cuppen, Edwin; Snippert, Hugo J.; Medema, Jan Paul; Kops, Geert J. P. L.; Clevers, Hans

    2015-01-01

    Crypt stem cells represent the cells of origin for intestinal neoplasia. Both mouse and human intestinal stem cells can be cultured in medium containing the stem-cell-niche factors WNT, R-spondin, epidermal growth factor (EGF) and noggin over long time periods as epithelial organoids that remain

  2. Alloimmune Responses of Humanized Mice to Human Pluripotent Stem Cell Therapeutics

    Directory of Open Access Journals (Sweden)

    Nigel G. Kooreman

    2017-08-01

    Full Text Available There is growing interest in using embryonic stem cell (ESC and induced pluripotent stem cell (iPSC derivatives for tissue regeneration. However, an increased understanding of human immune responses to stem cell-derived allografts is necessary for maintaining long-term graft persistence. To model this alloimmunity, humanized mice engrafted with human hematopoietic and immune cells could prove to be useful. In this study, an in-depth analysis of graft-infiltrating human lymphocytes and splenocytes revealed that humanized mice incompletely model human immune responses toward allogeneic stem cells and their derivatives. Furthermore, using an “allogenized” mouse model, we show the feasibility of reconstituting immunodeficient mice with a functional mouse immune system and describe a key role of innate immune cells in the rejection of mouse stem cell allografts.

  3. Nanoscale Mechanical Stimulation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    H Nikukar

    2014-05-01

    We observed significant responses after 1 and 2-week stimulations in cell number, cell shapes and phenotypical markers. Microarray was performed for all groups. Cell count showed normal cell growth with stimulation. However, cell surface area, cell perimeter, and arboration after 1-week stimulation showed significant increases. Immunofluorescent studies have showed significant increase in osteocalcin production after stimulation. Conclusions: Nanoscale mechanical vibration showed significant changes in human mesenchymal stem cell behaviours. Cell morphology changed to become more polygonal and increased expression of the osteoblast markers were noted. These findings with gene regulation changes suggesting nanoscale mechanostimulation has stimulated osteoblastogenesis.  Keywords:  Mesenchymal, Nanoscale, Stem Cells.

  4. Canthin-6-one induces cell death, cell cycle arrest and differentiation in human myeloid leukemia cells.

    Science.gov (United States)

    Vieira Torquato, Heron F; Ribeiro-Filho, Antonio C; Buri, Marcus V; Araújo Júnior, Roberto T; Pimenta, Renata; de Oliveira, José Salvador R; Filho, Valdir C; Macho, Antonio; Paredes-Gamero, Edgar J; de Oliveira Martins, Domingos T

    2017-04-01

    Canthin-6-one is a natural product isolated from various plant genera and from fungi with potential antitumor activity. In the present study, we evaluate the antitumor effects of canthin-6-one in human myeloid leukemia lineages. Kasumi-1 lineage was used as a model for acute myeloid leukemia. Cells were treated with canthin-6-one and cell death, cell cycle and differentiation were evaluated in both total cells (Lin + ) and leukemia stem cell population (CD34 + CD38 - Lin -/low ). Among the human lineages tested, Kasumi-1 was the most sensitive to canthin-6-one. Canthin-6-one induced cell death with apoptotic (caspase activation, decrease of mitochondrial potential) and necrotic (lysosomal permeabilization, double labeling of annexin V/propidium iodide) characteristics. Moreover, canthin-6-one induced cell cycle arrest at G 0 /G 1 (7μM) and G 2 (45μM) evidenced by DNA content, BrdU incorporation and cyclin B1/histone 3 quantification. Canthin-6-one also promoted differentiation of Kasumi-1, evidenced by an increase in the expression of myeloid markers (CD11b and CD15) and the transcription factor PU.1. Furthermore, a reduction of the leukemic stem cell population and clonogenic capability of stem cells were observed. These results show that canthin-6-one can affect Kasumi-1 cells by promoting cell death, cell cycle arrest and cell differentiation depending on concentration used. Canthin-6-one presents an interesting cytotoxic activity against leukemic cells and represents a promising scaffold for the development of molecules for anti-leukemic applications, especially by its anti-leukemic stem cell activity. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Comparison of the glycosphingolipids of human-induced pluripotent stem cells and human embryonic stem cells.

    Science.gov (United States)

    Säljö, Karin; Barone, Angela; Vizlin-Hodzic, Dzeneta; Johansson, Bengt R; Breimer, Michael E; Funa, Keiko; Teneberg, Susann

    2017-04-01

    High expectations are held for human-induced pluripotent stem cells (hiPSC) since they are established from autologous tissues thus overcoming the risk of allogeneic immune rejection when used in regenerative medicine. However, little is known regarding the cell-surface carbohydrate antigen profile of hiPSC compared with human embryonic stem cells (hESC). Here, glycosphingolipids were isolated from an adipocyte-derived hiPSC line, and hiPSC and hESC glycosphingolipids were compared by concurrent characterization by binding assays with carbohydrate-recognizing ligands and mass spectrometry. A high similarity between the nonacid glycosphingolipids of hiPSC and hESC was found. The nonacid glycosphingolipids P1 pentaosylceramide, x2 pentaosylceramide and H type 1 heptaosylceramide, not previously described in human pluripotent stem cells (hPSC), were characterized in both hiPSC and hESC. The composition of acid glycosphingolipids differed, with increased levels of GM3 ganglioside, and reduced levels of GD1a/GD1b in hiPSC when compared with hESC. In addition, the hESC glycosphingolipids sulf-globopentaosylceramide and sialyl-globotetraosylceramide were lacking in hiPSC. Neural stem cells differentiating from hiPSC had a reduced expression of sialyl-lactotetra, whereas expression of the GD1a ganglioside was significantly increased. Thus, while sialyl-lactotetra is a marker of undifferentiated hPSC, GD1a is a novel marker of neural differentiation. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. A DNA Vaccine Protects Human Immune Cells against Zika Virus Infection in Humanized Mice

    Directory of Open Access Journals (Sweden)

    Guohua Yi

    2017-11-01

    Full Text Available A DNA vaccine encoding prM and E protein has been shown to induce protection against Zika virus (ZIKV infection in mice and monkeys. However, its effectiveness in humans remains undefined. Moreover, identification of which immune cell types are specifically infected in humans is unclear. We show that human myeloid cells and B cells are primary targets of ZIKV in humanized mice. We also show that a DNA vaccine encoding full length prM and E protein protects humanized mice from ZIKV infection. Following administration of the DNA vaccine, humanized DRAG mice developed antibodies targeting ZIKV as measured by ELISA and neutralization assays. Moreover, following ZIKV challenge, vaccinated animals presented virtually no detectable virus in human cells and in serum, whereas unvaccinated animals displayed robust infection, as measured by qRT-PCR. Our results utilizing humanized mice show potential efficacy for a targeted DNA vaccine against ZIKV in humans.

  7. Molecular aging and rejuvenation of human muscle stem cells

    DEFF Research Database (Denmark)

    Carlson, Morgan E; Suetta, Charlotte; Conboy, Michael J

    2009-01-01

    . Our findings establish key evolutionarily conserved mechanisms of human stem cell aging. We find that satellite cells are maintained in aged human skeletal muscle, but fail to activate in response to muscle attrition, due to diminished activation of Notch compounded by elevated transforming growth...... factor beta (TGF-beta)/phospho Smad3 (pSmad3). Furthermore, this work reveals that mitogen-activated protein kinase (MAPK)/phosphate extracellular signal-regulated kinase (pERK) signalling declines in human muscle with age, and is important for activating Notch in human muscle stem cells. This molecular......Very little remains known about the regulation of human organ stem cells (in general, and during the aging process), and most previous data were collected in short-lived rodents. We examined whether stem cell aging in rodents could be extrapolated to genetically and environmentally variable humans...

  8. Generation of Corneal Keratocytes from Human Embryonic Stem Cells.

    Science.gov (United States)

    Hertsenberg, Andrew J; Funderburgh, James L

    2016-01-01

    Human Embryonic Stem Cells (hESC) offer an important resource as a limitless supply of any differentiated cell type of the human body. Keratocytes, cells from the corneal stroma, may have the potential for restoration of vision in cell therapy and biomedical engineering applications, but these specialized cells are not readily expanded in vitro. Here we describe a two-part method to produce keratocytes from the H1 hESC cell line. The hESC cells, maintained and expanded in feeder-free culture medium are first differentiated to neural crest cells using the stromal-derived inducing activity (SDIA) of the PA6 mouse embryonic fibroblast cell line. The resulting neural crest cells are selected by their expression of cell-surface CD271 and subsequently cultured as 3D pellets in a defined differentiation medium to induce a keratocyte phenotype.

  9. In vitro proliferation of adult human beta-cells.

    Directory of Open Access Journals (Sweden)

    Sabine Rutti

    Full Text Available A decrease in functional beta-cell mass is a key feature of type 2 diabetes. Glucagon-like peptide 1 (GLP-1 analogues induce proliferation of rodent beta-cells. However, the proliferative capacity of human beta-cells and its modulation by GLP-1 analogues remain to be fully investigated. We therefore sought to quantify adult human beta-cell proliferation in vitro and whether this is affected by the GLP-1 analogue liraglutide.Human islets from 7 adult cadaveric organ donors were dispersed into single cells. Beta-cells were purified by FACS. Non-sorted cells and the beta-cell enriched ("beta-cells" population were plated on extracellular matrix from rat (804G and human bladder carcinoma cells (HTB9 or bovine corneal endothelial ECM (BCEC. Cells were maintained in culture+/-liraglutide for 4 days in the presence of BrdU.Rare human beta-cell proliferation could be observed either in the purified beta-cell population (0.051±0.020%; 22 beta-cells proliferating out of 84'283 beta-cells counted or in the non-sorted cell population (0.055±0.011%; 104 proliferating beta-cells out of 232'826 beta-cells counted, independently of the matrix or the culture conditions. Liraglutide increased human beta-cell proliferation on BCEC in the non-sorted cell population (0.082±0.034% proliferating beta-cells vs. 0.017±0.008% in control, p<0.05.These results indicate that adult human beta-cell proliferation can occur in vitro but remains an extremely rare event with these donors and particular culture conditions. Liraglutide increases beta-cell proliferation only in the non-sorted cell population and only on BCEC. However, it cannot be excluded that human beta-cells may proliferate to a greater extent in situ in response to natural stimuli.

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

    Science.gov (United States)

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

    2017-08-02

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

  11. Identification of molecules derived from human fibroblast feeder cells that support the proliferation of human embryonic stem cells

    DEFF Research Database (Denmark)

    Anisimov, Sergey V.; Christophersen, Nicolaj S.; Correia, Ana S.

    2011-01-01

    The majority of human embryonic stem cell lines depend on a feeder cell layer for continuous growth in vitro, so that they can remain in an undifferentiated state. Limited knowledge is available concerning the molecular mechanisms that underlie the capacity of feeder cells to support both...... the proliferation and pluripotency of these cells. Importantly, feeder cells generally lose their capacity to support human embryonic stem cell proliferation in vitro following long-term culture. In this study, we performed large-scale gene expression profiles of human foreskin fibroblasts during early...... foreskin fibroblasts to serve as feeder cells for human embryonic stem cell cultures. Among these, the C-KIT, leptin and pigment epithelium-derived factor (PEDF) genes were the most interesting candidates....

  12. Nucleosome Organization in Human Embryonic Stem Cells.

    Directory of Open Access Journals (Sweden)

    Puya G Yazdi

    Full Text Available The fundamental repeating unit of eukaryotic chromatin is the nucleosome. Besides being involved in packaging DNA, nucleosome organization plays an important role in transcriptional regulation and cellular identity. Currently, there is much debate about the major determinants of the nucleosome architecture of a genome and its significance with little being known about its role in stem cells. To address these questions, we performed ultra-deep sequencing of nucleosomal DNA in two human embryonic stem cell lines and integrated our data with numerous epigenomic maps. Our analyses have revealed that the genome is a determinant of nucleosome organization with transcriptionally inactive regions characterized by a "ground state" of nucleosome profiles driven by underlying DNA sequences. DNA sequence preferences are associated with heterogeneous chromatin organization around transcription start sites. Transcription, histone modifications, and DNA methylation alter this "ground state" by having distinct effects on both nucleosome positioning and occupancy. As the transcriptional rate increases, nucleosomes become better positioned. Exons transcribed and included in the final spliced mRNA have distinct nucleosome profiles in comparison to exons not included at exon-exon junctions. Genes marked by the active modification H3K4m3 are characterized by lower nucleosome occupancy before the transcription start site compared to genes marked by the inactive modification H3K27m3, while bivalent domains, genes associated with both marks, lie exactly in the middle. Combinatorial patterns of epigenetic marks (chromatin states are associated with unique nucleosome profiles. Nucleosome organization varies around transcription factor binding in enhancers versus promoters. DNA methylation is associated with increasing nucleosome occupancy and different types of methylations have distinct location preferences within the nucleosome core particle. Finally, computational

  13. Human interleukin for DA cells or leukemia inhibitory factor is released by Vero cells in human embryo coculture.

    Science.gov (United States)

    Papaxanthos-Roche, A; Taupin, J L; Mayer, G; Daniel, J Y; Moreau, J F

    1994-09-01

    In the light of the newly discovered implications of human interleukin for DA cells and leukemia inhibitory factor in embryology, we searched for the presence of this soluble cytokine in the supernatant of Vero cell coculture systems. Using a bioassay as well as a specific ELISA, we demonstrated that Vero cells are able to release large quantities of human interleukin for DA cells and leukemia inhibitory factor in the embryo-growing medium of such cocultures.

  14. Acquisition of T regulatory function in cathepsin L-inhibited T cells by eye-derived CTLA-2alpha during inflammatory conditions.

    Science.gov (United States)

    Sugita, Sunao; Horie, Shintaro; Nakamura, Orie; Maruyama, Kazuichi; Takase, Hiroshi; Usui, Yoshihiko; Takeuchi, Masaru; Ishidoh, Kazumi; Koike, Masato; Uchiyama, Yasuo; Peters, Christoph; Yamamoto, Yoshimi; Mochizuki, Manabu

    2009-10-15

    Pigment epithelium isolated from the eye possesses immunosuppressive properties such as regulatory T (Treg) cell induction; e.g., cultured retinal pigment epithelium (RPE) converts CD4(+) T cells into Treg cells in vitro. RPE constitutively expresses a novel immunosuppressive factor, CTLA-2alpha, which is a cathepsin L (CathL) inhibitor, and this molecule acts via RPE to induce Treg cells. To clarify CTLA-2alpha's role in the T cell response to RPE in ocular inflammation, we used the experimental autoimmune uveitis (EAU) animal model to examine this new immunosuppressive property of RPE. In EAU models, TGF-beta, but not IFN-gamma inflammatory cytokines, promotes the up-regulation of the expression of CTLA-2alpha in RPE. Similarly, CTLA-2alpha via RPE was able to promote TGF-beta production by the CD4(+) T cells. The RPE-exposed T cells (RPE-induced Treg cells) greatly produced TGF-beta and suppressed bystander effector T cells. There was less expression of CathL by the RPE-exposed T cells, and CathL-inhibited T cells were able to acquire the Treg phenotype. Moreover, CathL-deficient mice spontaneously produced Treg cells, with the increase in T cells potentially providing protection against ocular inflammation. More importantly, CD4(+) T cells from EAU in CathL knockout mice or rCTLA-2alpha from EAU animals were found to contain a high population of forkhead box p3(+) T cells. In both EAU models, there was significant suppression of the ocular inflammation. These results indicate that RPE secretes CTLA-2alpha, thereby enabling the bystander T cells to be converted into Treg cells via TGF-beta promotion.

  15. Enhanced Detection of Sub-Retinal Pigment Epithelial Cell Layer Deposits in Human and Murine Tissue: Imaging Zinc as a Biomarker for Age-Related Macular Degeneration (An American Ophthalmological Society Thesis).

    Science.gov (United States)

    van Kuijk, Frederik J G M; McPherson, Scott W; Roehrich, Heidi

    2017-08-01

    Understanding the apparent paradoxical role of zinc in the pathogenesis and prevention of age-related macular degeneration (AMD) has been limited by the lack of animal models for its detection in sub-retinal epithelial deposits (drusen), a definitive early hallmark of AMD. In-vitro studies using Zinpyr-1 showed drusen contained high levels of zinc, but the probe was not suitable for in-vivo studies. This study compares Zinpyr-1 to ZPP1, a new fluorescein-based probe for zinc, to assess the potential of ZPP1 for in-vivo detection of zinc in drusen. Flat mounts of human sub-RPE tissue using the probes were analyzed by fluorescence and confocal microscopy. Flat mounts of sub-RPE tissue from mice deficient in superoxide dismutase isoform-1 (CuZn-SOD-KO) or isoform-2 (Mn-SOD-RPE-KO) were analyzed with sub-RPE deposits confirmed by histology. Drusen are detected in greater numbers and intensity with ZPP1 compared to Zinpyr-1. Using ZPP1, drusen was detected in a sample from a 46-year old human donor without ocular history, suggesting that ZPP1 might be sensitive enough to detect drusen at an early stage. With CuZn-SOD KO mice, ZPP1 detected sub-RPE deposits at 10 months of age, whereas Zinpyr-1 required 14 months. Detection of sub-RPE deposits by ZPP1 was greatly enhanced compared to Zinpyr-1. This enhanced sensitivity will allow for more insightful analysis of zinc in AMD using human specimens and mouse models. This could result in the development of a sensitive in-vivo probe to enhance research on the role zinc in drusen formation and the early clinical diagnosis of AMD.

  16. Current applications of human pluripotent stem cells: possibilities and challenges.

    Science.gov (United States)

    Ho, Pai-Jiun; Yen, Men-Luh; Yet, Shaw-Fang; Yen, B Linju

    2012-01-01

    Stem cells are self-renewable cells with the differentiation capacity to develop into somatic cells with biological functions. This ability to sustain a renewable source of multi- and/or pluripotential differentiation has brought new hope to the field of regenerative medicine in terms of cell therapy and tissue engineering. Moreover, stem cells are invaluable tools as in vitro models for studying diverse fields, from basic scientific questions such as developmental processes and lineage commitment, to practical application including drug screening and testing. The stem cells with widest differentiation potential are pluripotent stem cells (PSCs), which are rare cells with the ability to generate somatic cells from all three germ layers. PSCs are considered the most optimal choice for therapeutic potential of stem cells, bringing new impetus to the field of regenerative medicine. In this article, we discuss the therapeutic potential of human PSCs (hPSCs) including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs), reviewing the current preclinical and clinical data using these stem cells. We describe the classification of different sources of hPSCs, ongoing research, and currently encountered clinical obstacles of these novel and versatile human stem cells.

  17. Differential cytotoxic effects of 7-dehydrocholesterol-derived oxysterols on cultured retina-derived cells: Dependence on sterol structure, cell type, and density.

    Science.gov (United States)

    Pfeffer, Bruce A; Xu, Libin; Porter, Ned A; Rao, Sriganesh Ramachandra; Fliesler, Steven J

    2016-04-01

    Tissue accumulation of 7-dehydrocholesterol (7DHC) is a hallmark of Smith-Lemli-Opitz Syndrome (SLOS), a human inborn error of the cholesterol (CHOL) synthesis pathway. Retinal 7DHC-derived oxysterol formation occurs in the AY9944-induced rat model of SLOS, which exhibits a retinal degeneration characterized by selective loss of photoreceptors and associated functional deficits, Müller cell hypertrophy, and engorgement of the retinal pigment epithelium (RPE) with phagocytic inclusions. We evaluated the relative effects of four 7DHC-derived oxysterols on three retina-derived cell types in culture, with respect to changes in cellular morphology and viability. 661W (photoreceptor-derived) cells, rMC-1 (Müller glia-derived) cells, and normal diploid monkey RPE (mRPE) cells were incubated for 24 h with dose ranges of either 7-ketocholesterol (7kCHOL), 5,9-endoperoxy-cholest-7-en-3β,6α-diol (EPCD), 3β,5α-dihydroxycholest-7-en-6-one (DHCEO), or 4β-hydroxy-7-dehydrocholesterol (4HDHC); CHOL served as a negative control (same dose range), along with appropriate vehicle controls, while staurosporine (Stsp) was used as a positive cytotoxic control. For 661W cells, the rank order of oxysterol potency was: EPCD > 7kCHOL > DHCEO > 4HDHC ≈ CHOL. EC50 values were higher for confluent vs. subconfluent cultures. 661W cells exhibited much higher sensitivity to EPCD and 7kCHOL than either rMC-1 or mRPE cells, with the latter being the most robust when challenged, either at confluence or in sub-confluent cultures. When tested on rMC-1 and mRPE cells, EPCD was again an order of magnitude more potent than 7kCHOL in compromising cellular viability. Hence, 7DHC-derived oxysterols elicit differential cytotoxicity that is dose-, cell type-, and cell density-dependent. These results are consistent with the observed progressive, photoreceptor-specific retinal degeneration in the rat SLOS model, and support the hypothesis that 7DHC-derived oxysterols are causally linked to that

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

    Directory of Open Access Journals (Sweden)

    Chen Lei

    2011-06-01

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

  19. Human dental pulp stem cells: Applications in future regenerative medicine

    Science.gov (United States)

    Potdar, Pravin D; Jethmalani, Yogita D

    2015-01-01

    Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine. PMID:26131314

  20. Comprehensive evaluation of leukocyte lineage derived from human hematopoietic cells in humanized mice.

    Science.gov (United States)

    Takahashi, Masayuki; Tsujimura, Noriyuki; Otsuka, Kensuke; Yoshino, Tomoko; Mori, Tetsushi; Matsunaga, Tadashi; Nakasono, Satoshi

    2012-04-01

    Recently, humanized animals whereby a part of the animal is biologically engineered using human genes or cells have been utilized to overcome interspecific differences. Herein, we analyzed the detail of the differentiation states of various human leukocyte subpopulations in humanized mouse and evaluated comprehensively the similarity of the leukocyte lineage between humanized mice and humans. Humanized mice were established by transplanting human CD34(+) cord blood cells into irradiated severely immunodeficient NOD/Shi-scid/IL2Rγ(null) (NOG) mice, and the phenotypes of human cells contained in bone marrow, thymus, spleen and peripheral blood from the mice were analyzed at monthly intervals until 4 months after cell transplantation. The analysis revealed that transplanted human hematopoietic stem cells via the caudal vein homed and engrafted themselves successfully at the mouse bone marrow. Subsequently, the differentiated leukocytes migrated to the various tissues. Almost all of the leukocytes within the thymus were human cells. Furthermore, analysis of the differentiation states of human leukocytes in various tissues and organs indicated that it is highly likely that the human-like leukocyte lineage can be developed in mice. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  1. Wharton's Jelly Derived Mesenchymal Stem Cells: Comparing Human and Horse.

    Science.gov (United States)

    Merlo, Barbara; Teti, Gabriella; Mazzotti, Eleonora; Ingrà, Laura; Salvatore, Viviana; Buzzi, Marina; Cerqueni, Giorgia; Dicarlo, Manuela; Lanci, Aliai; Castagnetti, Carolina; Iacono, Eleonora

    2018-08-01

    Wharton's jelly (WJ) is an important source of mesenchymal stem cells (MSCs) both in human and other animals. The aim of this study was to compare human and equine WJMSCs. Human and equine WJMSCs were isolated and cultured using the same protocols and culture media. Cells were characterized by analysing morphology, growth rate, migration and adhesion capability, immunophenotype, differentiation potential and ultrastructure. Results showed that human and equine WJMSCs have similar ultrastructural details connected with intense synthetic and metabolic activity, but differ in growth, migration, adhesion capability and differentiation potential. In fact, at the scratch assay and transwell migration assay, the migration ability of human WJMSCs was higher (P cells, while the volume of spheroids obtained after 48 h of culture in hanging drop was larger than the volume of equine ones (P cell adhesion ability. This can also revealed in the lower doubling time of equine cells (3.5 ± 2.4 days) as compared to human (6.5 ± 4.3 days) (P cell doubling after 44 days of culture observed for the equine (20.3 ± 1.7) as compared to human cells (8.7 ± 2.4) (P cells showed an higher chondrogenic and osteogenic differentiation ability (P staminal phenotype in human and equine WJMSCs, they showed different properties reflecting the different sources of MSCs.

  2. induced acute cytotoxicity in human cervical epithelial carcinoma cells

    African Journals Online (AJOL)

    Molecular basis of arsenite (As +3 )-induced acute cytotoxicity in human cervical epithelial carcinoma cells. ... Libyan Journal of Medicine ... Methods: After performing cytotoxic assays on a human epithelial carcinoma cell line, expression analysis was done by quantitative polymerase chain reaction, western blotting, and ...

  3. Novel human multiple myeloma cell line UHKT-893

    Czech Academy of Sciences Publication Activity Database

    Uherková, L.; Vančurová, I.; Vyhlídalová, I.; Pleschnerová, M.; Špička, I.; Mihalová, R.; Březinová, J.; Hodný, Zdeněk; Čermáková, K.; Polanská, V.; Marinov, I.; Jedelský, P.L.; Kuželová, K.; Stöckbauer, P.

    2013-01-01

    Roč. 37, č. 3 (2013), s. 320-326 ISSN 0145-2126 Institutional support: RVO:68378050 Keywords : human myeloma cell line * human multiple myeloma * plasma cell * IL-6 dependence * immunoglobulin * free light chain Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.692, year: 2013

  4. 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 β 1 subunit of Na + , K + -ATPase plays an important role in this mechanism because homotypic β 1 -β 1 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 β 2 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 β 2 isoform and immunofluorescence analysis revealed an apparent apical distribution of the β 2 subunit. qPCR results showed a time-dependent increase in the level of β 2 isoform mRNA, suggesting regulation at the transcriptional level. Moreover, silencing the expression of the β 2 isoform in ARPE-19 cells resulted in a decrease in the apical localization of the pump, as assessed by the mislocalization of the α 2 subunit in that domain. Our results demonstrate that the apical polarization of Na + , K + -ATPase in RPE cells depends on the expression of the β 2 subunit.

  5. Mutation in the RPE65 gene causing hereditary retinal dystrophy in the Briard dogs: application of a new detection method

    Czech Academy of Sciences Publication Activity Database

    Bechyňová, Renata; Dostál, Jaromír; Stratil, Antonín; Jílek, F.; Horák, Pavel

    2008-01-01

    Roč. 53, č. 4 (2008), s. 176-179 ISSN 1212-1819 R&D Projects: GA AV ČR 1QS500450578; GA ČR GD523/03/H076 Institutional research plan: CEZ:AV0Z50450515 Keywords : RPE65 gene * CSNB * dog Subject RIV: EG - Zoology Impact factor: 0.735, year: 2008

  6. Human induced pluripotent stem cells on autologous feeders.

    Directory of Open Access Journals (Sweden)

    Kazutoshi Takahashi

    Full Text Available BACKGROUND: For therapeutic usage of induced Pluripotent Stem (iPS cells, to accomplish xeno-free culture is critical. Previous reports have shown that human embryonic stem (ES cells can be maintained in feeder-free condition. However, absence of feeder cells can be a hostile environment for pluripotent cells and often results in karyotype abnormalities. Instead of animal feeders, human fibroblasts can be used as feeder cells of human ES cells. However, one still has to be concerned about the existence of unidentified pathogens, such as viruses and prions in these non-autologous feeders. METHODOLOGY/PRINCIPAL FINDINGS: This report demonstrates that human induced Pluripotent Stem (iPS cells can be established and maintained on isogenic parental feeder cells. We tested four independent human skin fibroblasts for the potential to maintain self-renewal of iPS cells. All the fibroblasts tested, as well as their conditioned medium, were capable of maintaining the undifferentiated state and normal karyotypes of iPS cells. Furthermore, human iPS cells can be generated on isogenic parental fibroblasts as feeders. These iPS cells carried on proliferation over 19 passages with undifferentiated morphologies. They expressed undifferentiated pluripotent cell markers, and could differentiate into all three germ layers via embryoid body and teratoma formation. CONCLUSIONS/SIGNIFICANCE: These results suggest that autologous fibroblasts can be not only a source for iPS cells but also be feeder layers. Our results provide a possibility to solve the dilemma by using isogenic fibroblasts as feeder layers of iPS cells. This is an important step toward the establishment of clinical grade iPS cells.

  7. The association between human papillomavirus and oropharyngeal squamous cell Carcinoma

    DEFF Research Database (Denmark)

    Walvik, Lena; Svensson, Amanda Björk; Friborg, Jeppe

    2016-01-01

    carcinoma using the Bradford Hill criteria. The strength of the association is supported by, detection of human papillomavirus infection and antibodies prior to oropharyngeal squamous cell carcinoma. This is furthermore reinforced by the absence of human papillomavirus DNA in healthy tonsils...... incidence in human papillomavirus positive oropharyngeal squamous cell carcinoma is associated with sexual behaviour. These associations have been repeatedly observed and are in accordance with our current knowledge. The time relation between cause and effect remains the main challenge, due to the lack...... of well-defined premalignant lesions. However, a causal relationship between human papillomavirus infection and oropharyngeal squamous cell carcinoma seems evident....

  8. Freeze-Dried Human Red Blood Cells

    Science.gov (United States)

    1992-04-15

    period in the liquid state. 2. The levels of glycolytic intermediates (ATP, adenosine 5’triphosphate; 2,3-DPG 2, 3- diphosphoglycerate ) in rehydrated...8217 diphosphate, ADP; adenosine 5 monophosphate, AMP; 2,3- diphosphoglycerate . 2.3-DPG and lactate: (2) measurement of cell indices (mean cell volume (MCV), mean...monophosphate: 2,3-DPG. 2.3- diphosphoglycerate : MCV. Mean Cell Volume: MCH, Mean Cell Hemoglobin: MCHC, Mean Cell Hemoglobin Concentrations. ** Lactate levels

  9. CD1 and mycobacterial lipids activate human T cells.

    Science.gov (United States)

    Van Rhijn, Ildiko; Moody, D Branch

    2015-03-01

    For decades, proteins were thought to be the sole or at least the dominant source of antigens for T cells. Studies in the 1990s demonstrated that CD1 proteins and mycobacterial lipids form specific targets of human αβ T cells. The molecular basis by which T-cell receptors (TCRs) recognize CD1-lipid complexes is now well understood. Many types of mycobacterial lipids function as antigens in the CD1 system, and new studies done with CD1 tetramers identify T-cell populations in the blood of tuberculosis patients. In human populations, a fundamental difference between the CD1 and major histocompatibility complex systems is that all humans express nearly identical CD1 proteins. Correspondingly, human CD1 responsive T cells show evidence of conserved TCRs. In addition to natural killer T cells and mucosal-associated invariant T (MAIT cells), conserved TCRs define other subsets of human T cells, including germline-encoded mycolyl-reactive (GEM) T cells. The simple immunogenetics of the CD1 system and new investigative tools to measure T-cell responses in humans now creates a situation in which known lipid antigens can be developed as immunodiagnostic and immunotherapeutic reagents for tuberculosis disease. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. On the development of extragonadal and gonadal human germ cells

    Directory of Open Access Journals (Sweden)

    A. Marijne Heeren

    2016-02-01

    Full Text Available Human germ cells originate in an extragonadal location and have to migrate to colonize the gonadal primordia at around seven weeks of gestation (W7, or five weeks post conception. Many germ cells are lost along the way and should enter apoptosis, but some escape and can give rise to extragonadal germ cell tumors. Due to the common somatic origin of gonads and adrenal cortex, we investigated whether ectopic germ cells were present in the human adrenals. Germ cells expressing DDX4 and/or POU5F1 were present in male and female human adrenals in the first and second trimester. However, in contrast to what has been described in mice, where ‘adrenal’ and ‘ovarian’ germ cells seem to enter meiosis in synchrony, we were unable to observe meiotic entry in human ‘adrenal’ germ cells until W22. By contrast, ‘ovarian’ germ cells at W22 showed a pronounced asynchronous meiotic entry. Interestingly, we observed that immature POU5F1+ germ cells in both first and second trimester ovaries still expressed the neural crest marker TUBB3, reminiscent of their migratory phase. Our findings highlight species-specific differences in early gametogenesis between mice and humans. We report the presence of a population of ectopic germ cells in the human adrenals during development.

  11. Defective repair of UV-damaged DNA in human tumor and SV40-transformed human cells but not in adenovirus-transformed human cells

    International Nuclear Information System (INIS)

    Rainbow, A.J.

    1989-01-01

    The DNA repair capacities of five human tumor cell lines, one SV40-transformed human cell line and one adenovirus-transformed human cell line were compared with that of normal human fibroblasts using a sensitive host cell reactivation (HCR) technique. Unirradiated and UV-irradiated suspensions of adenovirus type 2 (Ad 2) were assayed for their ability to form viral structural antigens (Vag) in the various cell types using immunofluorescent staining. The survival of Vag formation for UV-irradiated Ad 2 was significantly reduced in all the human tumor cell lines and the SV40-transformed human line compared to the normal human fibroblasts, but was apparently normal in the adenovirus-transformed human cells. D 0 values for the UV survival of Ad 2 Vag synthesis in the tumor and virally transformed lines expressed as a percentage of that obtained on normal fibroblast strains were used as a measure of DNA repair capacity. Percent HCR values ranged from 26 to 53% in the tumor cells. These results indicate a deficiency in the repair of UV-induced DNA damage associated with human tumorigenesis and the transformation of human cells by SV40 but not the transformation of human cells by adenovirus. (author)

  12. Generation of hepatocyte- and endocrine pancreatic-like cells from human induced endodermal progenitor cells

    NARCIS (Netherlands)

    Sambathkumar, Rangarajan; Akkerman, Renate; Dastidar, Sumitava; Roelandt, Philip; Kumar, Manoj; Bajaj, Manmohan; Mestre Rosa, Ana Rita; Helsen, Nicky; Vanslembrouck, Veerle; Kalo, Eric; Khurana, Satish; Laureys, Jos; Gysemans, Conny; Faas, Marijke M; de Vos, Paul; Verfaillie, Catherine M

    2018-01-01

    Multipotent Adult Progenitor Cells (MAPCs) are one potential stem cell source to generate functional hepatocytes or β-cells. However, human MAPCs have less plasticity than pluripotent stem cells (PSCs), as their ability to generate endodermal cells is not robust. Here we studied the role of 14

  13. Proteomic analysis of human blastocoel fluid and blastocyst cells

    DEFF Research Database (Denmark)

    Jensen, Pernille; Beck, Hans Christian; Petersen, Jørgen

    2013-01-01

    Human embryonic stem cells (hESCs) are derived from the inner cell mass (ICM) of the blastocyst and can differentiate into any cell type in the human body. These cells hold a great potential for regenerative medicine, but to obtain enough cells needed for medical treatment, culture is required......, the blastocoel fluid, which is in contact with all the cells in the blastocyst, including hESCs. Fifty-three surplus human blastocysts were donated after informed consent, and blastocoel fluid was isolated by micromanipulation. Using highly sensitive nano-high-pressure liquid chromatography-tandem mass...... from the ICM of the human blastocyst are exposed to via the blastocoel fluid. These results can be an inspiration for the development of improved culture conditions for hESCs....

  14. Abnormal number cell division of human thyroid anaplastic carcinoma cell line, SW 1736

    Directory of Open Access Journals (Sweden)

    Keiichi Ikeda

    2015-12-01

    Full Text Available Cell division, during which a mother cell usually divides into two daughter cells during one cell cycle, is the most important physiological event of cell biology. We observed one-to-four cell division during imaging of live SW1736 human thyroid anaplastic carcinoma cells transfected with a plasmid expressing the hybrid protein of green fluorescent protein and histone 2B (plasmid eGFP-H2B. Analysis of the images revealed a mother cell divided into four daughter cells. And one of the abnormally divided daughter cells subsequently formed a dinucleate cell.

  15. The use of human cells in biomedical research and testing.

    Science.gov (United States)

    Combes, Robert D

    2004-06-01

    The ability to use human cells in biomedical research and testing has the obvious advantage over the use of laboratory animals that the need for species extrapolation is obviated, due to the presence of more-relevant morphological, physiological and biochemical properties, including receptors. Moreover, human cells exhibit the same advantages as animal cells in culture in that different cell types can be used, from different tissues, with a wide range of techniques, to investigate a wide variety of biological phenomena in tissue culture. Human cells can also be grown as organotypic cultures to facilitate the extrapolation from cells to whole organisms. Human cell lines have been available for many years on an ad hoc basis from individual researchers, and also from recognised sources, such as the European Collection of Animal Cell Cultures (ECACC) and, in the USA, the Human Cell Culture Centre (HCCC). Such cells have usually been derived from tumours and this has restricted the variety of types of cells available. This problem has been addressed by using primary human cells that can be obtained from a variety of sources, such as cadavers, diseased tissue, skin strips, peripheral blood, buccal cavity smears, hair follicles and surgical waste from biopsy material that is unsuitable for transplantation purposes. However, primary human cells need to be obtained, processed, distributed and handled in a safe and ethical manner. They also have to be made available at the correct time to researchers very shortly after they become available. It is only comparatively recently that the safe and controlled acquisition of surgical waste and non-transplantable human tissues has become feasible with the establishment of several human tissue banks. Recently, the formation of a UK and European centralised network for human tissue supply has been initiated. The problems of short longevity and loss of specialisation in culture are being approached by: a) cell immortalisation to

  16. The response of human and rodent cells to hyperthermia

    International Nuclear Information System (INIS)

    Roizin-Towle, L.; Pirro, J.P.

    1991-01-01

    Inherent cellular radiosensitivity in vitro has been shown to be a good predictor of human tumor response in vivo. In contrast, the importance of the intrinsic thermosensitivity of normal and neoplastic human cells as a factor in the responsiveness of human tumors to adjuvant hyperthermia has never been analyzed systematically. A comparison of thermal sensitivity and thermo-radiosensitization in four rodent and eight human-derived cell lines was made in vitro. Arrhenius plots indicated that the rodent cells were more sensitive to heat killing than the human, and the break-point was 0.5 degrees C higher for the human than rodent cells. The relationship between thermal sensitivity and the interaction of heat with X rays at low doses was documented by thermal enhancement ratios (TER's). Cells received either a 1 hr exposure to 43 degrees C or a 20 minute treatment at 45 degrees C before exposure to 300 kVp X rays. Thermal enhancement ratios ranged from 1.0 to 2.7 for human cells heated at 43 degrees C and from 2.1 to 5.3 for heat exposures at 45 degrees C. Thermal enhancement ratios for rodent cells were generally 2 to 3 times higher than for human cells, because of the fact that the greater thermosensitivity of rodent cells results in a greater enhancement of radiation damage. Intrinsic thermosensitivity of human cells has relevance to the concept of thermal dose; intrinsic thermo-radiosensitization of a range of different tumor cells is useful in documenting the interactive effects of radiation combined with heat

  17. Generation of Functional Thymic Epithelium from Human Embryonic Stem Cells that Supports Host T Cell Development

    OpenAIRE

    Parent, Audrey V.; Russ, Holger A.; Khan, Imran S.; LaFlam, Taylor N.; Metzger, Todd C.; Anderson, Mark S.; Hebrok, Matthias

    2013-01-01

    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 th...

  18. Stepwise development of MAIT cells in mouse and human.

    Directory of Open Access Journals (Sweden)

    Emmanuel Martin

    2009-03-01

    Full Text Available Mucosal-associated invariant T (MAIT cells display two evolutionarily conserved features: an invariant T cell receptor (TCRalpha (iTCRalpha chain and restriction by the nonpolymorphic class Ib major histocompatibility complex (MHC molecule, MHC-related molecule 1 (MR1. MR1 expression on thymus epithelial cells is not necessary for MAIT cell development but their accumulation in the gut requires MR1 expressing B cells and commensal flora. MAIT cell development is poorly known, as these cells have not been found in the thymus so far. Herein, complementary human and mouse experiments using an anti-humanValpha7.2 antibody and MAIT cell-specific iTCRalpha and TCRbeta transgenic mice in different genetic backgrounds show that MAIT cell development is a stepwise process, with an intra-thymic selection followed by peripheral expansion. Mouse MAIT cells are selected in an MR1-dependent manner both in fetal thymic organ culture and in double iTCRalpha and TCRbeta transgenic RAG knockout mice. In the latter mice, MAIT cells do not expand in the periphery unless B cells are added back by adoptive transfer, showing that B cells are not required for the initial thymic selection step but for the peripheral accumulation. In humans, contrary to natural killer T (NKT cells, MAIT cells display a naïve phenotype in the thymus as well as in cord blood where they are in low numbers. After birth, MAIT cells acquire a memory phenotype and expand dramatically, up to 1%-4% of blood T cells. Finally, in contrast with NKT cells, human MAIT cell development is independent of the molecular adaptor SAP. Interestingly, mouse MAIT cells display a naïve phenotype and do not express the ZBTB16 transcription factor, which, in contrast, is expressed by NKT cells and the memory human MAIT cells found in the periphery after birth. In conclusion, MAIT cells are selected by MR1 in the thymus on a non-B non-T hematopoietic cell, and acquire a memory phenotype and expand in the

  19. Human induced pluripotent stem cells: A disruptive innovation.

    Science.gov (United States)

    De Vos, J; Bouckenheimer, J; Sansac, C; Lemaître, J-M; Assou, S

    2016-01-01

    This year (2016) will mark the 10th anniversary of the discovery of induced pluripotent stem cells (iPSCs). The finding that the transient expression of four transcription factors can radically remodel the epigenome, transcriptome and metabolome of differentiated cells and reprogram them into pluripotent stem cells has been a major and groundbreaking technological innovation. In this review, we discuss the major applications of this technology that we have grouped in nine categories: a model to study cell fate control; a model to study pluripotency; a model to study human development; a model to study human tissue and organ physiology; a model to study genetic diseases in a dish; a tool for cell rejuvenation; a source of cells for drug screening; a source of cells for regenerative medicine; a tool for the production of human organs in animals. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Chromosome aberration induction in human diploid fibroblast and epithelial cells

    International Nuclear Information System (INIS)

    Scott, D.

    1986-01-01

    The relative sensitivity of cultured human fibroblasts and epithelial cells to radiation-induced chromosomal aberrations was investigated. Lung fibroblast and kidney epithelial cells from the same fetus were compared, as were skin fibroblasts and epithelial keratinocytes from the same foreskin sample. After exposure of proliferating fetal cells to 1.5 Gy X-rays there was a very similar aberration yield in the fibroblasts and epithelial cells. Observations of either little or no difference in chromosomal sensitivity between human fibroblasts and epithelial cells give added confidence that quantitative cytogenetic data obtained from cultured fibroblasts are relevant to the question of sensitivity of epithelial cells which are the predominant cell type in human cancers. (author)

  1. Genome editing: a robust technology for human stem cells.

    Science.gov (United States)

    Chandrasekaran, Arun Pandian; Song, Minjung; Ramakrishna, Suresh

    2017-09-01

    Human pluripotent stem cells comprise induced pluripotent and embryonic stem cells, which have tremendous potential for biological and therapeutic applications. The development of efficient technologies for the targeted genome alteration of stem cells in disease models is a prerequisite for utilizing stem cells to their full potential. Genome editing of stem cells is possible with the help of synthetic nucleases that facilitate site-specific modification of a gene of interest. Recent advances in genome editing techniques have improved the efficiency and speed of the development of stem cells for human disease models. Zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system are powerful tools for editing DNA at specific loci. Here, we discuss recent technological advances in genome editing with site-specific nucleases in human stem cells.

  2. Applied Developmental Biology: Making Human Pancreatic Beta Cells for Diabetics.

    Science.gov (United States)

    Melton, Douglas A

    2016-01-01

    Understanding the genes and signaling pathways that determine the differentiation and fate of a cell is a central goal of developmental biology. Using that information to gain mastery over the fates of cells presents new approaches to cell transplantation and drug discovery for human diseases including diabetes. © 2016 Elsevier Inc. All rights reserved.

  3. Human papilloma virus prevalence in laryngeal squamous cell carcinoma.

    Science.gov (United States)

    Gungor, A; Cincik, H; Baloglu, H; Cekin, E; Dogru, S; Dursun, E

    2007-08-01

    To determine the prevalence and type of human papilloma virus deoxyribonucleic acid (DNA) in cases of laryngeal squamous cell carcinoma. We analysed the prevalence of human papilloma virus infection in archived paraffin block specimens taken from 99 cases of laryngeal squamous cell carcinoma between 1990 and 2005, using polymerase chain reaction techniques. Biopsy specimens from five proven verrucous skin lesions were used as positive controls, and peripheral blood samples from five healthy volunteers were used as negative controls. Four test samples were found to have inadequate deoxyribonucleic acid purity and were therefore excluded from the study. Human papilloma virus deoxyribonucleic acid was detected in seven of 95 cases of laryngeal squamous cell carcinoma (7.36 per cent). Human papilloma virus genotyping revealed double human papilloma virus infection in three cases and single human papilloma virus infection in the remaining four cases. The human papilloma virus genotypes detected were 6, 11 and 16 (the latter detected in only one case). In our series, a very low human papilloma virus prevalence was found among laryngeal squamous cell carcinoma cases. The human papilloma virus genotypes detected were mostly 6 and/or 11, and 16 in only one case. To the best of our knowledge, this is the first report of human papilloma virus prevalence in laryngeal squamous cell carcinoma, based on polymerase chain reaction genotyping in a Turkish population.

  4. Hexavalent chromium induces chromosome instability in human urothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Wise, Sandra S. [Wise Laboratory of Environmental and Genetic Toxicology, Maine Center for Toxicology and Environmental Health, Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Holmes, Amie L. [Wise Laboratory of Environmental and Genetic Toxicology, Maine Center for Toxicology and Environmental Health, Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Department of Radiation Oncology, Dana Farber Cancer Institute, 450 Brookline Ave., Boston, MA 02215 (United States); Liou, Louis [Department of Pathology, Boston University School of Medicine, 670 Albany St., Boston, MA 02118 (United States); Adam, Rosalyn M. [Department of Surgery, Harvard Medical School, Boston, MA 02115 (United States); Wise, John Pierce Sr., E-mail: john.wise@louisville.edu [Wise Laboratory of Environmental and Genetic Toxicology, Maine Center for Toxicology and Environmental Health, Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States)

    2016-04-01

    Numerous metals are well-known human bladder carcinogens. Despite the significant occupational and public health concern of metals and bladder cancer, the carcinogenic mechanisms remain largely unknown. Chromium, in particular, is a metal of concern as incidences of bladder cancer have been found elevated in chromate workers, and there is an increasing concern for patients with metal hip implants. However, the impact of hexavalent chromium (Cr(VI)) on bladder cells has not been studied. We compared chromate toxicity in two bladder cell lines; primary human urothelial cells and hTERT-immortalized human urothelial cells. Cr(VI) induced a concentration- and time-dependent increase in chromosome damage in both cell lines, with the hTERT-immortalized cells exhibiting more chromosome damage than the primary cells. Chronic exposure to Cr(VI) also induced a concentration-dependent increase in aneuploid metaphases in both cell lines which was not observed after a 24 h exposure. Aneuploidy induction was higher in the hTERT-immortalized cells. When we correct for uptake, Cr(VI) induces a similar amount of chromosome damage and aneuploidy suggesting that the differences in Cr(VI) sensitivity between the two cells lines were due to differences in uptake. The increase in chromosome instability after chronic chromate treatment suggests this may be a mechanism for chromate-induced bladder cancer, specifically, and may be a mechanism for metal-induced bladder cancer, in general. - Highlights: • Hexavalent chromium is genotoxic to human urothelial cells. • Hexavalent chromium induces aneuploidy in human urothelial cells. • hTERT-immortalized human urothelial cells model the effects seen in primary urothelial cells. • Hexavalent chromium has a strong likelihood of being carcinogenic for bladder tissue.

  5. Male germline stem cells in non-human primates

    Directory of Open Access Journals (Sweden)

    S. Sharma

    2017-09-01

    Full Text Available Over the past few decades, several studies have attempted to decipher the biology of mammalian germline stem cells (GSCs. These studies provide evidence that regulatory mechanisms for germ cell specification and migration are evolutionarily conserved across species. The characteristics and functions of primate GSCs are highly distinct from rodent species; therefore the findings from rodent models cannot be extrapolated to primates. Due to limited availability of human embryonic and testicular samples for research purposes, two non-human primate models (marmoset and macaque monkeys are extensively employed to understand human germline development and differentiation. This review provides a broader introduction to the in vivo and in vitro germline stem cell terminology from primordial to differentiating germ cells. Primordial germ cells (PGCs are the most immature germ cells colonizing the gonad prior to sex differentiation into testes or ovaries. PGC specification and migratory patterns among different primate species are compared in the review. It also reports the distinctions and similarities in expression patterns of pluripotency markers (OCT4A, NANOG, SALL4 and LIN28 during embryonic developmental stages, among marmosets, macaques and humans. This review presents a comparative summary with immunohistochemical and molecular evidence of germ cell marker expression patterns during postnatal developmental stages, among humans and non-human primates. Furthermore, it reports findings from the recent literature investigating the plasticity behavior of germ cells and stem cells in other organs of humans and monkeys. The use of non-human primate models would enable bridging the knowledge gap in primate GSC research and understanding the mechanisms involved in germline development. Reported similarities in regulatory mechanisms and germ cell expression profile in primates demonstrate the preclinical significance of monkey models for development of

  6. Cytotoxic human CD4(+) T cells

    NARCIS (Netherlands)

    van de Berg, Pablo J.; van Leeuwen, Ester M.; ten Berge, Ineke J.; van Lier, Rene

    2008-01-01

    The induction of adaptive immune responses critically depends on helper signals provided by CD4(+) T cells. These signals not only license antigen presenting cells (APC) to activate naïve CD8(+) T cells leading to the formation of vast numbers of cytotoxic T lymphocytes but also support the

  7. Human Red Cells With Paroxysmal Nocturnal Haemoglobinuria ...

    African Journals Online (AJOL)

    The purified cells were used as hosts for the culture of P.falciparum in vitro. Results show that GPI-linked molecules on the red cell surface are not required for the efficient entry of the parasites, and that the PNH red cells are competent to sustain the growth of P.falciparum. Nigerian Quarterly Journal of Hospital Medicine Vol ...

  8. Human papillomavirus 16 E5 induces bi-nucleated cell formation by cell-cell fusion

    International Nuclear Information System (INIS)

    Hu Lulin; Plafker, Kendra; Vorozhko, Valeriya; Zuna, Rosemary E.; Hanigan, Marie H.; Gorbsky, Gary J.; Plafker, Scott M.; Angeletti, Peter C.; Ceresa, Brian P.

    2009-01-01

    Human papillomaviruses (HPV) 16 is a DNA virus encoding three oncogenes - E5, E6, and E7. The E6 and E7 proteins have well-established roles as inhibitors of tumor suppression, but the contribution of E5 to malignant transformation is controversial. Using spontaneously immortalized human keratinocytes (HaCaT cells), we demonstrate that expression of HPV16 E5 is necessary and sufficient for the formation of bi-nucleated cells, a common characteristic of precancerous cervical lesions. Expression of E5 from non-carcinogenic HPV6b does not produce bi-nucleate cells. Video microscopy and biochemical analyses reveal that bi-nucleates arise through cell-cell fusion. Although most E5-induced bi-nucleates fail to propagate, co-expression of HPV16 E6/E7 enhances the proliferation of these cells. Expression of HPV16 E6/E7 also increases bi-nucleated cell colony formation. These findings identify a new role for HPV16 E5 and support a model in which complementary roles of the HPV16 oncogenes lead to the induction of carcinogenesis

  9. Propagation of human spermatogonial stem cells in vitro.

    Science.gov (United States)

    Sadri-Ardekani, Hooman; Mizrak, Sefika C; van Daalen, Saskia K M; Korver, Cindy M; Roepers-Gajadien, Hermien L; Koruji, Morteza; Hovingh, Suzanne; de Reijke, Theo M; de la Rosette, Jean J M C H; van der Veen, Fulco; de Rooij, Dirk G; Repping, Sjoerd; van Pelt, Ans M M

    2009-11-18

    Young boys treated with high-dose chemotherapy are often confronted with infertility once they reach adulthood. Cryopreserving testicular tissue before chemotherapy and autotransplantation of spermatogonial stem cells at a later stage could theoretically allow for restoration of fertility. To establish in vitro propagation of human spermatogonial stem cells from small testicular biopsies to obtain an adequate number of cells for successful transplantation. Study performed from April 2007 to July 2009 using testis material donated by 6 adult men who underwent orchidectomy as part of prostate cancer treatment. Testicular cells were isolated and cultured in supplemented StemPro medium; germline stem cell clusters that arose were subcultured on human placental laminin-coated dishes in the same medium. Presence of spermatogonia was determined by reverse transcriptase polymerase chain reaction and immunofluorescence for spermatogonial markers. To test for the presence of functional spermatogonial stem cells in culture, xenotransplantation to testes of immunodeficient mice was performed, and migrated human spermatogonial stem cells after transplantation were detected by COT-1 fluorescence in situ hybridization. The number of colonized spermatogonial stem cells transplanted at early and later points during culture were counted to determine propagation. Propagation of spermatogonial stem cells over time. Testicular cells could be cultured and propagated up to 15 weeks. Germline stem cell clusters arose in the testicular cell cultures from all 6 men and could be subcultured and propagated up to 28 weeks. Expression of spermatogonial markers on both the RNA and protein level was maintained throughout the entire culture period. In 4 of 6 men, xenotransplantation to mice demonstrated the presence of functional spermatogonial stem cells, even after prolonged in vitro culture. Spermatogonial stem cell numbers increased 53-fold within 19 days in the testicular cell culture and

  10. Identification of Human Cutaneous Basal Cell Carcinoma Cancer Stem Cells.

    Science.gov (United States)

    Morgan, Huw; Olivero, Carlotta; Patel, Girish K

    2018-04-20

    The cancer stem cell model states that a subset of tumor cells, called "cancer stem cells," can initiate and propagate tumor growth through self-renewal, high proliferative capacity, and their ability to recreate tumor heterogeneity. In basal cell carcinoma (BCC), we have shown that tumor cells that express the cell surface protein CD200 fulfill the cancer stem cell hypothesis. CD200+ CD45- BCC cells represent 0.05-3.96% of all BCC cells and reside in small clusters at the tumor periphery. Using a novel, reproducible in vivo xenograft growth assay, we determined that tumor-initiating cell (TIC) frequencies are approximately 1 per 1.5 million unsorted BCC cells. The CD200+ CD45- BCC subpopulation recreated BCC tumor growth in vivo with typical histological architecture and expression of sonic hedgehog-regulated genes. Reproducible in vivo BCC growth was achieved with as few as 10,000 CD200+ CD45- cells, representing ~1500-fold enrichment. The methods used to identify and purify CD200+ CD45- BCC cells, as well as characterize gene expression, are described herein.

  11. Interactions between human mesenchymal stem cells and natural killer cells.

    Science.gov (United States)

    Sotiropoulou, Panagiota A; Perez, Sonia A; Gritzapis, Angelos D; Baxevanis, Constantin N; Papamichail, Michael

    2006-01-01

    Mesenchymal stem cells (MSCs) are multipotent progenitor cells representing an attractive therapeutic tool for regenerative medicine. They possess unique immunomodulatory properties, being capable of suppressing T-cell responses and modifying dendritic cell differentiation, maturation, and function, whereas they are not inherently immunogenic, failing to induce alloreactivity to T cells and freshly isolated natural killer (NK) cells. To clarify the generation of host immune responses to implanted MSCs in tissue engineering and their potential use as immunosuppressive elements, the effect of MSCs on NK cells was investigated. We demonstrate that at low NK-to-MSC ratios, MSCs alter the phenotype of NK cells and suppress proliferation, cytokine secretion, and cyto-toxicity against HLA-class I- expressing targets. Some of these effects require cell-to-cell contact, whereas others are mediated by soluble factors, including transforming growth factor-beta1 and prostaglandin E2, suggesting the existence of diverse mechanisms for MSC-mediated NK-cell suppression. On the other hand, MSCs are susceptible to lysis by activated NK cells. Overall, these data improve our knowledge of interactions between MSCs and NK cells and consequently of their effect on innate immune responses and their contribution to the regulation of adaptive immunity, graft rejection, and cancer immunotherapy.

  12. Preferential radiosensitization of human prostatic carcinoma cells by mild hyperthermia

    International Nuclear Information System (INIS)

    Ryu, Samuel; Brown, Stephen L.; Kim, Sang-Hie; Khil, Mark S.; Kim, Jae Ho

    1996-01-01

    Purpose: Recent cell culture studies by us and others suggest that some human carcinoma cells are more sensitive to heat than are rodent cells following mild hyperthermia. In studying the cellular mechanism of enhanced thermosensitivity of human tumor cells to hyperthermia, prostatic carcinoma cells of human origin were found to be more sensitive to mild hyperthermia than other human cancer cells. The present study was designed to determine the magnitude of radiosensitization of human prostatic carcinoma cells by mild hyperthermia and to examine whether the thermal radiosensitization is related to the intrinsic thermosensitivity of cancer cells. Methods and Materials: Two human prostatic carcinoma cell lines (DU-145 and PC-3) and other carcinoma cells of human origin, in particular, colon (HT-29), breast (MCF-7), lung (A-549), and brain (U-251) were exposed to temperatures of 40-41 deg. C. Single acute dose rate radiation and fractionated radiation were combined with mild hyperthermia to determine thermal radiosensitization. The end point of the study was the colony-forming ability of single-plated cells. Results: DU-145 and PC-3 cells were found to be exceedingly thermosensitive to 41 deg. C for 24 h, relative to other cancer cell lines. Ninety percent of the prostatic cancer cells were killed by a 24 h heat exposure. Prostatic carcinoma cells exposed to a short duration of heating at 41 deg. C for 2 h resulted in a substantial enhancement of radiation-induced cytotoxicity. The thermal enhancement ratios (TERs) of single acute dose radiation following heat treatment 41 deg. C for 2 h were 2.0 in DU-145 cells and 1.4 in PC-3 cells. The TERs of fractionated irradiation combined with continuous heating at 40 deg. C were similarly in the range of 2.1 to 1.4 in prostate carcinoma cells. No significant radiosensitization was observed in MCF-7 and HT-29 cells under the same conditions. Conclusion: The present data suggest that a significant radiosensitization of

  13. Cloning the interleukin 1 receptor from human T cells

    International Nuclear Information System (INIS)

    Sims, J.E.; Acres, R.B.; Grubin, C.E.; McMahan, C.J.; Wignall, J.M.; March, C.J.; Dower, S.K.

    1989-01-01

    cDNA clones of the interleukin 1 (IL-1) receptor expressed in a human T-cell clone have been isolated by using a murine IL-1 receptor cDNA as a probe. The human and mouse receptors show a high degree of sequence conservation. Both are integral membrane proteins possessing a single membrane-spanning segment. Similar to the mouse receptor, the human IL-1 receptor contains a large cytoplasmic region and an extracellular, IL-1 binding portion composed of three immunoglobulin-like domains. When transfected into COS cells, the human IL-1 receptor cDNA clone leads to expression of two different affinity classes of receptors, with K a values indistinguishable from those determined for IL-1 receptors in the original T-cell clone. An IL-1 receptor expressed in human dermal fibroblasts has also been cloned and sequenced and found to be identical to the IL-1 receptor expressed in T cells

  14. Radiation response characteristics of human cell in vitro

    International Nuclear Information System (INIS)

    Hall, E.J.

    1987-01-01

    Improvements in tissue culture techniques and growth media have made it possible to culture a range of cells of human origin, both normal and malignant. The most recent addition to the list are endothelial cells. Interesting results have been obtained, some of which may have implications in Radiation Therapy. (i) Repair of Potentially Lethal Damage (PLDR) has been observed in all cell lines investigated; cells of normal origin repair PLD at least as well as malignant cells, which makes clinical trials of PLDR inhibitors of doubtful usefulness. (ii) PLD in fibroblasts of human origin appears to have a component that is repaired rapidly, in a matter of minutes, as well as a slower component that takes hours to repair. (iii) Sublethal damage repair, manifest by a dose-rate effect, has also been observed in all human cell lines tested. Cells of normal tissue origin, including fibroblasts and endothelial cells, exhibit a dose-rate effect that is intermediate between that for cells from traditionally resistant tumors (melanoma and osteosarcoma) and cells from more sensitive tumors (neuroblastoma and breast). (iv) Fibroblasts from patients with Ataxia Telangectasia (AT) are much more sensitive to x-rays, with a D/sub o/ about half that for normal human fibroblasts. Nevertheless repair of both PLD and SLD can be demonstrated in these cells

  15. Derivation of novel human ground state naive pluripotent stem cells.

    Science.gov (United States)

    Gafni, Ohad; Weinberger, Leehee; Mansour, Abed AlFatah; Manor, Yair S; Chomsky, Elad; Ben-Yosef, Dalit; Kalma, Yael; Viukov, Sergey; Maza, Itay; Zviran, Asaf; Rais, Yoach; Shipony, Zohar; Mukamel, Zohar; Krupalnik, Vladislav; Zerbib, Mirie; Geula, Shay; Caspi, Inbal; Schneir, Dan; Shwartz, Tamar; Gilad, Shlomit; Amann-Zalcenstein, Daniela; Benjamin, Sima; Amit, Ido; Tanay, Amos; Massarwa, Rada; Novershtern, Noa; Hanna, Jacob H

    2013-12-12

    Mouse embryonic stem (ES) cells are isolated from the inner cell mass of blastocysts, and can be preserved in vitro in a naive inner-cell-mass-like configuration by providing exogenous stimulation with leukaemia inhibitory factor (LIF) and small molecule inhibition of ERK1/ERK2 and GSK3β signalling (termed 2i/LIF conditions). Hallmarks of naive pluripotency include driving Oct4 (also known as Pou5f1) transcription by its distal enhancer, retaining a pre-inactivation X chromosome state, and global reduction in DNA methylation and in H3K27me3 repressive chromatin mark deposition on developmental regulatory gene promoters. Upon withdrawal of 2i/LIF, naive mouse ES cells can drift towards a primed pluripotent state resembling that of the post-implantation epiblast. Although human ES cells share several molecular features with naive mouse ES cells, they also share a variety of epigenetic properties with primed murine epiblast stem cells (EpiSCs). These include predominant use of the proximal enhancer element to maintain OCT4 expression, pronounced tendency for X chromosome inactivation in most female human ES cells, increase in DNA methylation and prominent deposition of H3K27me3 and bivalent domain acquisition on lineage regulatory genes. The feasibility of establishing human ground state naive pluripotency in vitro with equivalent molecular and functional features to those characterized in mouse ES cells remains to be defined. Here we establish defined conditions that facilitate the derivation of genetically unmodified human naive pluripotent stem cells from already established primed human ES cells, from somatic cells through induced pluripotent stem (iPS) cell reprogramming or directly from blastocysts. The novel naive pluripotent cells validated herein retain molecular characteristics and functional properties that are highly similar to mouse naive ES cells, and distinct from conventional primed human pluripotent cells. This includes competence in the generation

  16. Validity and reliability of the session-RPE method for quantifying training in Australian football: a comparison of the CR10 and CR100 scales.

    Science.gov (United States)

    Scott, Tannath J; Black, Cameron R; Quinn, John; Coutts, Aaron J

    2013-01-01

    The purpose of this study was to examine and compare the criterion validity and test-retest reliability of the CR10 and CR100 rating of perceived exertion (RPE) scales for team sport athletes that undertake high-intensity, intermittent exercise. Twenty-one male Australian football (AF) players (age: 19.0 ± 1.8 years, body mass: 83.92 ± 7.88 kg) participated the first part (part A) of this study, which examined the construct validity of the session-RPE (sRPE) method for quantifying training load in AF. Ten male athletes (age: 16.1 ± 0.5 years) participated in the second part of the study (part B), which compared the test-retest reliability of the CR10 and CR100 RPE scales. In part A, the validity of the sRPE method was assessed by examining the relationships between sRPE, and objective measures of internal (i.e., heart rate) and external training load (i.e., distance traveled), collected from AF training sessions. Part B of the study assessed the reliability of sRPE through examining the test-retest reliability of sRPE during 3 different intensities of controlled intermittent running (10, 11.5, and 13 km·h(-1)). Results from part A demonstrated strong correlations for CR10- and CR100-derived sRPE with measures of internal training load (Banisters TRIMP and Edwards TRIMP) (CR10: r = 0.83 and 0.83, and CR100: r = 0.80 and 0.81, p training load (distance, higher speed running and player load) for both the CR10 (r = 0.81, 0.71, and 0.83) and CR100 (r = 0.78, 0.69, and 0.80) were significant (p reliability for both the CR10 (31.9% CV) and CR100 (38.6% CV) RPE scales after short bouts of intermittent running. Collectively, these results suggest both CR10- and CR100-derived sRPE methods have good construct validity for assessing training load in AF. The poor levels of reliability revealed under field testing indicate that the sRPE method may not be sensible to detecting small changes in exercise intensity during brief intermittent running bouts. Despite this limitation

  17. Concise Review: Kidney Generation with Human Pluripotent Stem Cells.

    Science.gov (United States)

    Morizane, Ryuji; Miyoshi, Tomoya; Bonventre, Joseph V

    2017-11-01

    Chronic kidney disease (CKD) is a worldwide health care problem, resulting in increased cardiovascular mortality and often leading to end-stage kidney disease, where patients require kidney replacement therapies such as hemodialysis or kidney transplantation. Loss of functional nephrons contributes to the progression of CKD, which can be attenuated but not reversed due to inability to generate new nephrons in human adult kidneys. Human pluripotent stem cells (hPSCs), by virtue of their unlimited self-renewal and ability to differentiate into cells of all three embryonic germ layers, are attractive sources for kidney regenerative therapies. Recent advances in stem cell biology have identified key signals necessary to maintain stemness of human nephron progenitor cells (NPCs) in vitro, and led to establishment of protocols to generate NPCs and nephron epithelial cells from human fetal kidneys and hPSCs. Effective production of large amounts of human NPCs and kidney organoids will facilitate elucidation of developmental and pathobiological pathways, kidney disease modeling and drug screening as well as kidney regenerative therapies. We summarize the recent studies to induce NPCs and kidney cells from hPSCs, studies of NPC expansion from mouse and human embryonic kidneys, and discuss possible approaches in vivo to regenerate kidneys with cell therapies and the development of bioengineered kidneys. Stem Cells 2017;35:2209-2217. © 2017 AlphaMed Press.

  18. Chemical Conversion of Human Fibroblasts into Functional Schwann Cells

    Directory of Open Access Journals (Sweden)

    Eva C. Thoma

    2014-10-01

    Full Text Available Direct transdifferentiation of somatic cells is a promising approach to obtain patient-specific cells for numerous applications. However, conversion across germ-layer borders often requires ectopic gene expression with unpredictable side effects. Here, we present a gene-free approach that allows efficient conversion of human fibroblasts via a transient progenitor stage into Schwann cells, the major glial cell type of peripheral nerves. Using a multikinase inhibitor, we transdifferentiated fibroblasts into transient neural precursors that were subsequently further differentiated into Schwann cells. The resulting induced Schwann cells (iSCs expressed numerous Schwann cell-specific proteins and displayed neurosupportive and myelination capacity in vitro. Thus, we established a strategy to obtain mature Schwann cells from human postnatal fibroblasts under chemically defined conditions without the introduction of ectopic genes.

  19. Rho GTPase expression in human myeloid cells.

    Directory of Open Access Journals (Sweden)

    Suzanne F G van Helden

    Full Text Available Myeloid cells are critical for innate immunity and the initiation of adaptive immunity. Strict regulation of the adhesive and migratory behavior is essential for proper functioning of these cells. Rho GTPases are important regulators of adhesion and migration; however, it is unknown which Rho GTPases are expressed in different myeloid cells. Here, we use a qPCR-based approach to investigate Rho GTPase expression in myeloid cells.We found that the mRNAs encoding Cdc42, RhoQ, Rac1, Rac2, RhoA and RhoC are the most abundant. In addition, RhoG, RhoB, RhoF and RhoV are expressed at low levels or only in specific cell types. More differentiated cells along the monocyte-lineage display lower levels of Cdc42 and RhoV, while RhoC mRNA is more abundant. In addition, the Rho GTPase expression profile changes during dendritic cell maturation with Rac1 being upregulated and Rac2 downregulated. Finally, GM-CSF stimulation, during macrophage and osteoclast differentiation, leads to high expression of Rac2, while M-CSF induces high levels of RhoA, showing that these cytokines induce a distinct pattern. Our data uncover cell type specific modulation of the Rho GTPase expression profile in hematopoietic stem cells and in more differentiated cells of the myeloid lineage.

  20. Immune surveillance properties of human NK cell-derived exosomes.

    Science.gov (United States)

    Lugini, Luana; Cecchetti, Serena; Huber, Veronica; Luciani, Francesca; Macchia, Gianfranco; Spadaro, Francesca; Paris, Luisa; Abalsamo, Laura; Colone, Marisa; Molinari, Agnese; Podo, Franca; Rivoltini, Licia; Ramoni, Carlo; Fais, Stefano

    2012-09-15

    Exosomes are nanovesicles released by normal and tumor cells, which are detectable in cell culture supernatant and human biological fluids, such as plasma. Functions of exosomes released by "normal" cells are not well understood. In fact, several studies have been carried out on exosomes derived from hematopoietic cells, but very little is known about NK cell exosomes, despite the importance of these cells in innate and adaptive immunity. In this paper, we report that resting and activated NK cells, freshly isolated from blood of healthy donors, release exosomes expressing typical protein markers of NK cells and containing killer proteins (i.e., Fas ligand and perforin molecules). These nanovesicles display cytotoxic activity against several tumor cell lines and activated, but not resting, immune cells. We also show that NK-derived exosomes undergo uptake by tumor target cells but not by resting PBMC. Exosomes purified from plasma of healthy donors express NK cell markers, including CD56+ and perforin, and exert cytotoxic activity against different human tumor target cells and activated immune cells as well. The results of this study propose an important role of NK cell-derived exosomes in immune surveillance and homeostasis. Moreover, this study supports the use of exosomes as an almost perfect example of biomimetic nanovesicles possibly useful in future therapeutic approaches against various diseases, including tumors.

  1. A review of human cell radiosensitivity in vitro

    International Nuclear Information System (INIS)

    Deschavanne, Patrick J.; Fertil, Bernard

    1996-01-01

    The survival curves of 694 human cell lines irradiated in exponentially growing phase in vitro were collected from the literature. Among them, 271 were derived from tumors, 423 were nontransformed fibroblasts and other normal cell strains from healthy people or people with some genetic disorders. Seventy-six different cell types are identified, and a specific radiosensitivity could be associated with each, using D-bar and surviving fraction at 2 Gy. Technical factors such as culture medium, feeder cells, and scoring method were found to affect intrinsic radiosensitivity. In particular, the cell type is not a discriminating factor when cells are studied in agar. Results obtained with cells irradiated in agar must be used cautiously, depending on how the cells were prepared for the experiments. The use of feeder cells narrows the range of radiosensitivity of human cells. For cells irradiated as monolayer, it was possible to build a scale of radiosensitivity according to cell type, ranging, in terms of D-bar from 0.6 Gy for the most sensitive cell lines to more than 4 Gy for the most resistant. Considering that, in most cases, we could estimate the variation of radiosensitivity within each cell type, our classification among cell types can be used by researchers to place their results in the context of the literature

  2. Cell sources for in vitro human liver cell culture models

    Science.gov (United States)

    Freyer, Nora; Damm, Georg; Seehofer, Daniel; Knöspel, Fanny

    2016-01-01

    In vitro liver cell culture models are gaining increasing importance in pharmacological and toxicological research. The source of cells used is critical for the relevance and the predictive value of such models. Primary human hepatocytes (PHH) are currently considered to be the gold standard for hepatic in vitro culture models, since they directly reflect the specific metabolism and functionality of the human liver; however, the scarcity and difficult logistics of PHH have driven researchers to explore alternative cell sources, including liver cell lines and pluripotent stem cells. Liver cell lines generated from hepatomas or by genetic manipulation are widely used due to their good availability, but they are generally altered in certain metabolic functions. For the past few years, adult and pluripotent stem cells have been attracting increasing attention, due their ability to proliferate and to differentiate into hepatocyte-like cells in vitro. However, controlling the differentiation of these cells is still a challenge. This review gives an overview of the major human cell sources under investigation for in vitro liver cell culture models, including primary human liver cells, liver cell lines, and stem cells. The promises and challenges of different cell types are discussed with a focus on the complex 2D and 3D culture approaches under investigation for improving liver cell functionality in vitro. Finally, the specific application options of individual cell sources in pharmacological research or disease modeling are described. PMID:27385595

  3. Calorimetric signatures of human cancer cells and their nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Todinova, S. [Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, Sofia 1113 (Bulgaria); Stoyanova, E. [Department of Molecular Immunology, Institute of Biology and Immunology of Reproduction, Bulgarian Academy of Sciences, Tzarigradsko shose Blvd. 73, Sofia 1113 (Bulgaria); Krumova, S., E-mail: sakrumo@gmail.com [Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, Sofia 1113 (Bulgaria); Iliev, I. [Institute of Experimental Morphology, Pathology and Anthropology with Museum, Acad. G. Bonchev Str., Bl. 25, Sofia 1113 (Bulgaria); Taneva, S.G. [Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, Sofia 1113 (Bulgaria)

    2016-01-10

    Graphical abstract: - Highlights: • Two temperature ranges are distinguished in the thermograms of cells/nuclei. • Different thermodynamic properties of cancer and normal human cells/nuclei. • Dramatic reduction of the enthalpy of the low-temperature range in cancer cells. • Oxaliplatin and 5-FU affect the nuclear matrix proteins and the DNA stability. - Abstract: The human cancer cell lines HeLa, JEG-3, Hep G2, SSC-9, PC-3, HT-29, MCF7 and their isolated nuclei were characterized by differential scanning calorimetry. The calorimetric profiles differed from normal human fibroblast (BJ) cells in the two well distinguished temperature ranges—the high-temperature range (H{sub T}, due to DNA-containing structures) and the low-temperature range (L{sub T}, assigned to the nuclear matrix and cellular proteins). The enthalpy of the L{sub T} range, and, respectively the ratio of the enthalpies of the L{sub T}- vs. H{sub T}-range, ΔH{sub L}/ΔH{sub H}, is strongly reduced for all cancer cells compared to normal fibroblasts. On the contrary, for most of the cancer nuclei this ratio is higher compared to normal nuclei. The HT-29 human colorectal cancer cells/nuclei differed most drastically from normal human fibroblast cells/nuclei. Our data also reveal that the treatment of HT-29 cancer cells with cytostatic drugs affects not only the DNA replication but also the cellular proteome.

  4. Stem cell markers in the heart of the human newborn

    Directory of Open Access Journals (Sweden)

    Armando Faa

    2016-07-01

    Full Text Available The identification of cardiac progenitor cells in mammals raises the possibility that the human heart contains a population of stem cells capable of generating cardiomyocytes and coronary vessels. Several recent studies now show that the different cell types that characterize the adult human heart arise from a common ancestor. Human cardiac stem cells differentiate into cardiomyocytes, and, in lesser extent, into smooth muscle and endothelial cells. The characterization of human cardiac stem cells (CSCs has important clinical implications. In recent years, CD117 (c-kit has been reported to mark a subtype of stem/progenitor cells in the human heart, with stem cell-like properties, including the ability to self-renewal and clonogenicity multipotentiality. Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015 · Cagliari (Italy · October 31st, 2015 · Stem cells: present and future Guest Editors: Gavino Faa, Vassilios Fanos, Antonio Giordano

  5. Hurdles to clinical translation of human induced pluripotent stem cells

    OpenAIRE

    Neofytou, Evgenios; O’Brien, Connor Galen; Couture, Larry A.; Wu, Joseph C.

    2015-01-01

    Human pluripotent stem cells are known to have the capacity to renew indefinitely, being intrinsically able to differentiate into many different cell types. These characteristics have generated tremendous enthusiasm about the potential applications of these cells in regenerative medicine. However, major challenges remain with the development and testing of novel experimental stem cell therapeutics in the field. In this Review, we focus on the nature of the preclinical challenges and discuss p...

  6. Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin.

    Science.gov (United States)

    Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F; Psathaki, Olympia E; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R; Schlenke, Peter; Zaehres, Holm

    2015-01-01

    Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34(+) hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34(+) hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34(+) cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential. Copyright© Ferrata Storti Foundation.

  7. Generation of Spinal Motor Neurons from Human Pluripotent Stem Cells.

    Science.gov (United States)

    Santos, David P; Kiskinis, Evangelos

    2017-01-01

    Human embryonic stem cells (ESCs) are characterized by their unique ability to self-renew indefinitely, as well as to differentiate into any cell type of the human body. Induced pluripotent stem cells (iPSCs) share these salient characteristics with ESCs and can easily be generated from any given individual by reprogramming somatic cell types such as fibroblasts or blood cells. The spinal motor neuron (MN) is a specialized neuronal subtype that synapses with muscle to control movement. Here, we present a method to generate functional, postmitotic, spinal motor neurons through the directed differentiation of ESCs and iPSCs by the use of small molecules. These cells can be utilized to study the development and function of human motor neurons in healthy and disease states.

  8. Rhein Induces Apoptosis in Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ching-Yao Chang

    2012-01-01

    Full Text Available Human breast cancers cells overexpressing HER2/neu are more aggressive tumors with poor prognosis, and resistance to chemotherapy. This study investigates antiproliferation effects of anthraquinone derivatives of rhubarb root on human breast cancer cells. Of 7 anthraquinone derivatives, only rhein showed antiproliferative and apoptotic effects on both HER2-overexpressing MCF-7 (MCF-7/HER2 and control vector MCF-7 (MCF-7/VEC cells. Rhein induced dose- and time-dependent manners increase in caspase-9-mediated apoptosis correlating with activation of ROS-mediated activation of NF-κB- and p53-signaling pathways in both cell types. Therefore, this study highlighted rhein as processing anti-proliferative activity against HER2 overexpression or HER2-basal expression in breast cancer cells and playing important roles in apoptotic induction of human breast cancer cells.

  9. Comparative mutagenesis of human cells in vivo and in vitro

    International Nuclear Information System (INIS)

    Thilly, W.G.

    1990-01-01

    Our goal is to develop the tools of mutational spectrometry in order to discover the cause(s) of genetic change in somatic and germinal cells in humans. Our study of the spectrum of point mutations in human mitochrondrial DNA sequences has revealed that there are multiple point mutation hotspots in each of four separate sequences in the mitochrondrial genome. These spectra were revealed by a combination of high fidelity PCR (modified T 7 polymerase) and denaturing gradient gel electrophoresis which has a limit of detection of about 10 -3 . There appear to be identical hotspot mutations in both cultured B cell and fresh human blood T cell samples

  10. Cardiac Progenitor Cell Extraction from Human Auricles

    KAUST Repository

    Di Nardo, Paolo

    2017-02-22

    For many years, myocardial tissue has been considered terminally differentiated and, thus, incapable of regenerating. Recent studies have shown, instead, that cardiomyocytes, at least in part, are slowly substituted by new cells originating by precursor cells mostly embedded into the heart apex and in the atria. We have shown that an elective region of progenitor cell embedding is represented by the auricles, non-contractile atria appendages that can be easily sampled without harming the patient. The protocol here reported describes how from auricles a population of multipotent, cardiogenic cells can be isolated, cultured, and differentiated. Further studies are needed to fully exploit this cell population, but, sampling auricles, it could be possible to treat cardiac patients using their own cells circumventing rejection or organ shortage limitations.

  11. Immune and Inflammatory Cell Composition of Human Lung Cancer Stroma.

    Directory of Open Access Journals (Sweden)

    G-Andre Banat

    Full Text Available Recent studies indicate that the abnormal microenvironment of tumors may play a critical role in carcinogenesis, including lung cancer. We comprehensively assessed the number of stromal cells, especially immune/inflammatory cells, in lung cancer and evaluated their infiltration in cancers of different stages, types and metastatic characteristics potential. Immunohistochemical analysis of lung cancer tissue arrays containing normal and lung cancer sections was performed. This analysis was combined with cyto-/histomorphological assessment and quantification of cells to classify/subclassify tumors accurately and to perform a high throughput analysis of stromal cell composition in different types of lung cancer. In human lung cancer sections we observed a significant elevation/infiltration of total-T lymphocytes (CD3+, cytotoxic-T cells (CD8+, T-helper cells (CD4+, B cells (CD20+, macrophages (CD68+, mast cells (CD117+, mononuclear cells (CD11c+, plasma cells, activated-T cells (MUM1+, B cells, myeloid cells (PD1+ and neutrophilic granulocytes (myeloperoxidase+ compared with healthy donor specimens. We observed all of these immune cell markers in different types of lung cancers including squamous cell carcinoma, adenocarcinoma, adenosquamous cell carcinoma, small cell carcinoma, papillary adenocarcinoma, metastatic adenocarcinoma, and bronchioloalveolar carcinoma. The numbers of all tumor-associated immune cells (except MUM1+ cells in stage III cancer specimens was significantly greater than those in stage I samples. We observed substantial stage-dependent immune cell infiltration in human lung tumors suggesting that the tumor microenvironment plays a critical role during lung carcinogenesis. Strategies for therapeutic interference with lung cancer microenvironment should consider the complexity of its immune cell composition.

  12. 5-Fluorouracil-radiation interactions in human colon adenocarcinoma cells

    International Nuclear Information System (INIS)

    Buchholz, Daniel J.; Lepek, Katherine J.; Rich, Tyvin A.; Murray, David

    1995-01-01

    Purpose: To determine the effect of cellular proliferation and cell cycle stage on the ability of postirradiation 5-fluorouracil (5-FU) to radiosensitize cultured human colon adenocarcinoma Clone A cells. Methods and Materials: Cell survival curves were generated for irradiated: (a) log- and plateau-phase Clone A cells; and (b) Clone A cells separated by centrifugal elutriation into the various phases of the cell cycle; with and without postirradiation treatment with 100 μg/ml 5-FU. Results: Postirradiation treatment with 5-FU sensitized proliferating cells to a greater degree than it sensitized cells growing in plateau phase. The β component of cell kill in log-phase cells was increased by a factor of 1.5 with a sensitizer enhancement ratio of 1.21 at the 0.01 survival level. Plateau-phase cells showed less radiosensitization (sensitizer enhancement ratio of 1.13 at the 0.01 survival level); however, there was a mild increase in both α and β kill in plateau-phase cells. Elutriated G 1 cells were the most radiosensitive, independent of treatment with 5-FU. The phase of the cell cycle had little effect on the ability of fluorouracil to radiosensitize Clone A cells. Conclusion: Proliferating cells are more susceptible to radiosensitization with 5-FU than plateau-phase cells are, but this effect appears to be independent of the phase of the cell cycle

  13. The contribution of human/non-human animal chimeras to stem cell research

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    Sonya Levine

    2017-10-01

    Full Text Available Chimeric animals are made up of cells from two separate zygotes. Human/non-human animal chimeras have been used for a number of research purposes, including human disease modeling. Pluripotent stem cell (PSC research has relied upon the chimera approach to examine the developmental potential of stem cells, to determine the efficacy of cell replacement therapies, and to establish a means of producing human organs. Based on ethical issues, this work has faced pushback from various sources including funding agencies. We discuss here the essential role these studies have played, from gaining a better understanding of human biology to providing a stepping stone to human disease treatments. We also consider the major ethical issues, as well as the current status of support for this work in the United States.

  14. The contribution of human/non-human animal chimeras to stem cell research.

    Science.gov (United States)

    Levine, Sonya; Grabel, Laura

    2017-10-01

    Chimeric animals are made up of cells from two separate zygotes. Human/non-human animal chimeras have been used for a number of research purposes, including human disease modeling. Pluripotent stem cell (PSC) research has relied upon the chimera approach to examine the developmental potential of stem cells, to determine the efficacy of cell replacement therapies, and to establish a means of producing human organs. Based on ethical issues, this work has faced pushback from various sources including funding agencies. We discuss here the essential role these studies have played, from gaining a better understanding of human biology to providing a stepping stone to human disease treatments. We also consider the major ethical issues, as well as the current status of support for this work in the United States. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Human pituitary and placental hormones control human insulin-like growth factor II secretion in human granulosa cells

    International Nuclear Information System (INIS)

    Ramasharma, K.; Li, C.H.

    1987-01-01

    Human granulosa cells cultured with calf serum actively proliferated for 18-20 generations and secreted progesterone into the medium; progesterone levels appeared to decline with increase in generation number. Cells cultured under serum-free conditions secreted significant amounts of progesterone and insulin-like growth factor II (IGF-II). The progesterone secretion was enhanced by the addition of human follitropin, lutropin, and chorionic gonadotropin but not by growth hormone. These cells, when challenged to varying concentrations of human growth hormone, human chorionic somatomammotropin, human prolactin, chorionic gonadotropin, follitropin, and lutropin, secreted IGF-II into the medium as measured by specific IGF-II RIA. Among these human hormones, chorionic gonadotropin, follitropin, and lutropin were most effective in inducing IGF-II secretion from these cells. When synthetic lutropin-releasing hormone and α-inhibin-92 were tested, only lutropin-releasing hormone was effective in releasing IGF-II. The results described suggest that cultured human granulosa cells can proliferate and actively secrete progesterone and IGF-II into the medium. IGF-II production in human granulosa cells was influenced by a multi-hormonal complex including human growth hormone, human chorionic somatomammotropin, and prolactin

  16. Size-dependent internalisation of folate-decorated nanoparticles via the pathways of clathrin and caveolae-mediated endocytosis in ARPE-19 cells.

    Science.gov (United States)

    Langston Suen, Wai-Leung; Chau, Ying

    2014-04-01

    We aim to quantify the effect of size and degree of folate loading of folate-decorated polymeric nanoparticles (NPs) on the kinetics of cellular uptake and the selection of endocytic pathways in retinal pigment epithelium (RPE) cells. In this study, methoxy-poly(ethylene glycol)-b-polycaprolactone (mPEG-b-PCL) and folate-functionalized PEG-b-PCL were synthesized for assembling into nanoparticles with sizes ranging from 50 nm to 250 nm. These nanoparticles were internalized into ARPE-19 (human RPE cell line) via receptor-mediated endocytosis. A two-step endocytosis process mathematical model was adopted to quantify binding affinity and uptake kinetics of nanoparticles in RPE cells in uptake and inhibition studies. Nanoparticles with 100% folate loading have highest binding affinity and uptake rate in RPE cells. Maximum uptake rate (Vmax) of nanoparticles increased as the size of particles decreased from 250 nm to 50 nm. Endocytic pathway study was studied by using chlorpromazine and methyl-β-cyclodextran (MβCD), which are clathrin- and caveolae-mediated endocytosis inhibitors, respectively. Both chlorpromazine and MβCD inhibited the uptake of folate-decorated nanoparticles. Inhibition constant (Ki) and maximum uptake rate (Vmax) revealed that 50 nm and 120 nm folate-decorated nanoparticles were found to be internalized via both clathrin- and caveolae-mediated endocytosis. The 250 nm folate-decorated nanoparticles, however, were only internalized via caveolae-mediated pathway. Increased uptake rate of folate-decorated NPs into RPE cells is observed with increasing degree of folate modification. These NPs utilize both clathrin- and caveolae-mediated receptor-mediated endocytosis pathways to enter RPE cells upon size variation. The 50 nm NPs are internalized the fastest, with clathrin-mediated endocytosis as the preferred route. Uptake of 250 nm particles is the slowest and is dominated by caveolae-mediated endocytosis. © 2013 Royal Pharmaceutical

  17. Hydroxytyrosol Protects against Oxidative DNA Damage in Human Breast Cells

    Directory of Open Access Journals (Sweden)

    José J. Gaforio

    2011-10-01

    Full Text Available Over recent years, several studies have related olive oil ingestion to a low incidence of several diseases, including breast cancer. Hydroxytyrosol and tyrosol are two of the major phenols present in virgin olive oils. Despite the fact that they have been linked to cancer prevention, there is no evidence that clarifies their effect in human breast tumor and non-tumor cells. In the present work, we present hydroxytyrosol and tyrosol’s effects in human breast cell lines. Our results show that hydroxytyrosol acts as a more efficient free radical scavenger than tyrosol, but both fail to affect cell proliferation rates, cell cycle profile or cell apoptosis in human mammary epithelial cells (MCF10A or breast cancer cells (MDA-MB-231 and MCF7. We found that hydroxytyrosol decreases the intracellular reactive oxygen species (ROS level in MCF10A cells but not in MCF7 or MDA-MB-231 cells while very high amounts of tyrosol is needed to decrease the ROS level in MCF10A cells. Interestingly, hydroxytyrosol prevents oxidative DNA damage in the three breast cell lines. Therefore, our data suggest that simple phenol hydroxytyrosol could contribute to a lower incidence of breast cancer in populations that consume virgin olive oil due to its antioxidant activity and its protection against oxidative DNA damage in mammary cells.

  18. Induction of apoptosis by eugenol in human breast cancer cells

    International Nuclear Information System (INIS)

    Vidhya, N.; Niranjali Devaraj, S.

    2011-01-01

    In the present study, potential anticancer effect of eugenol on inhibition of cell proliferation and induction of apoptosis in human MCF-7 breast cancer cells was investigated. Induction of cell death by eugenol was evaluated following MTT assay and monitoring lactate dehydrogenase released into the culture medium for cell viability and cytotoxicity, giemsa staining for morphological alterations, fluorescence microscopy analysis of cells using ethidium bromide and acridine orange and quantitation of DNA fragments for induction of apoptosis. Effect of eugenol on intracellular redox status of the human breast cancer cells was assessed by determining the level of glutathione and lipid peroxidation products (TBARS). Eugenol treatment inhibited the growth and proliferation of human MCF-7 breast cancer cells through induction of cell death, which was dose and time dependent. Microscopic examination of eugenol treated cells showed cell shrinkage, membrane blebbing and apoptotic body formation. Further, eugenol treatment also depleted the level of intracellular glutathione and increased the level of lipid peroxidation. The dose dependent increase in the percentage of apoptotic cells and DNA fragments suggested that apoptosis was involved in eugenol induced cell death and apoptosis might have played a role in the chemopreventive action of eugenol. (author)

  19. Inhibition of fatty acid metabolism reduces human myeloma cells proliferation.

    Directory of Open Access Journals (Sweden)

    José Manuel Tirado-Vélez

    Full Text Available Multiple myeloma is a haematological malignancy characterized by the clonal proliferation of plasma cells. It has been proposed that targeting cancer cell metabolism would provide a new selective anticancer therapeutic strategy. In this work, we tested the hypothesis that inhibition of β-oxidation and de novo fatty acid synthesis would reduce cell proliferation in human myeloma cells. We evaluated the effect of etomoxir and orlistat on fatty acid metabolism, glucose metabolism, cell cycle distribution, proliferation, cell death and expression of G1/S phase regulatory proteins in myeloma cells. Etomoxir and orlistat inhibited β-oxidation and de novo fatty acid synthesis respectively in myeloma cells, without altering significantly glucose metabolism. These effects were associated with reduced cell viability and cell cycle arrest in G0/G1. Specifically, etomoxir and orlistat reduced by 40-70% myeloma cells proliferation. The combination of etomoxir and orlistat resulted in an additive inhibitory effect on cell proliferation. Orlistat induced apoptosis and sensitized RPMI-8226 cells to apoptosis induction by bortezomib, whereas apoptosis was not altered by etomoxir. Finally, the inhibitory effect of both drugs on cell proliferation was associated with reduced p21 protein levels and phosphorylation levels of retinoblastoma protein. In conclusion, inhibition of fatty acid metabolism represents a potential therapeutic approach to treat human multiple myeloma.

  20. X-ray sensitivity of human tumor cells in vitro

    International Nuclear Information System (INIS)

    Weichselbaum, R.R.; Nove, J.; Little, J.B.

    1980-01-01

    Clonally-derived cells from ten human malignant tumors considered radiocurable (breast, neuroblastoma, medulloblastoma) or non-radiocurable (osteosarcoma, hypernephroma, glioblastoma, melanoma) were studied in cell culture and their in vitro x-ray survival curve parameters determined (anti n, D 0 ). There were no significant differences among the tumor cell lines suggesting that survival parameters in vitro do not explain differences in clinical radiocurability. Preliminary investigation with density inhibited human tumor cells indicate that such an approach may yield information regarding inherent cellular differences in radiocurability

  1. Radiosensitivity of normal human epidermal cells in culture

    International Nuclear Information System (INIS)

    Dover, R.; Potten, C.S.

    1983-01-01

    Using an in vitro culture system the authors have derived #betta#-radiation survival curves over a dose range 0-8 Gy for the clonogenic cells of normal human epidermis. The culture system used allows the epidermal cells to stratify and form a multi-layered sheet of keratinizing cells. The cultures appear to be a very good model for epidermis in vivo. The survival curves show a population which is apparently more sensitive than murine epidermis in vivo. It remains unclear whether this is an intrinsic difference between the species or is a consequence of the in vitro cultivation of the human cells. (author)

  2. Modeling human neurological disorders with induced pluripotent stem cells.

    Science.gov (United States)

    Imaizumi, Yoichi; Okano, Hideyuki

    2014-05-01

    Human induced pluripotent stem (iPS) cells obtained by reprogramming technology are a source of great hope, not only in terms of applications in regenerative medicine, such as cell transplantation therapy, but also for modeling human diseases and new drug development. In particular, the production of iPS cells from the somatic cells of patients with intractable diseases and their subsequent differentiation into cells at affected sites (e.g., neurons, cardiomyocytes, hepatocytes, and myocytes) has permitted the in vitro construction of disease models that contain patient-specific genetic information. For example, disease-specific iPS cells have been established from patients with neuropsychiatric disorders, including schizophrenia and autism, as well as from those with neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease. A multi-omics analysis of neural cells originating from patient-derived iPS cells may thus enable investigators to elucidate the pathogenic mechanisms of neurological diseases that have heretofore been unknown. In addition, large-scale screening of chemical libraries with disease-specific iPS cells is currently underway and is expected to lead to new drug discovery. Accordingly, this review outlines the progress made via the use of patient-derived iPS cells toward the modeling of neurological disorders, the testing of existing drugs, and the discovery of new drugs. The production of human induced pluripotent stem (iPS) cells from the patients' somatic cells and their subsequent differentiation into specific cells have permitted the in vitro construction of disease models that contain patient-specific genetic information. Furthermore, innovations of gene-editing technologies on iPS cells are enabling new approaches for illuminating the pathogenic mechanisms of human diseases. In this review article, we outlined the current status of neurological diseases-specific iPS cell research and described recently obtained

  3. Using Human Induced Pluripotent Stem Cells to Model Skeletal Diseases.

    Science.gov (United States)

    Barruet, Emilie; Hsiao, Edward C

    2016-01-01

    Musculoskeletal disorders affecting the bones and joints are major health problems among children and adults. Major challenges such as the genetic origins or poor diagnostics of severe skeletal disease hinder our understanding of human skeletal diseases. The recent advent of human induced pluripotent stem cells (human iPS cells) provides an unparalleled opportunity to create human-specific models of human skeletal diseases. iPS cells have the ability to self-renew, allowing us to obtain large amounts of starting material, and have the potential to differentiate into any cell types in the body. In addition, they can carry one or more mutations responsible for the disease of interest or be genetically corrected to create isogenic controls. Our work has focused on modeling rare musculoskeletal disorders including fibrodysplasia ossificans progressive (FOP), a congenital disease of increased heterotopic ossification. In this review, we will discuss our experiences and protocols differentiating human iPS cells toward the osteogenic lineage and their application to model skeletal diseases. A number of critical challenges and exciting new approaches are also discussed, which will allow the skeletal biology field to harness the potential of human iPS cells as a critical model system for understanding diseases of abnormal skeletal formation and bone regeneration.

  4. Human natural killer cell committed thymocytes and their relation to the T cell lineage

    NARCIS (Netherlands)

    Sánchez, M. J.; Spits, H.; Lanier, L. L.; Phillips, J. H.

    1993-01-01

    Recent studies have demonstrated that mature natural killer (NK) cells can be grown from human triple negative (TN; CD3-, CD4-, CD8-) thymocytes, suggesting that a common NK/T cell precursor exists within the thymus that can give rise to both NK cells and T cells under appropriate conditions. In the

  5. Generation of Human Induced Pluripotent Stem Cells from Peripheral Blood Mononuclear Cells Using Sendai Virus.

    Science.gov (United States)

    Soares, Filipa A C; Pedersen, Roger A; Vallier, Ludovic

    2016-01-01

    This protocol describes the efficient isolation of peripheral blood mononuclear cells from circulating blood via density gradient centrifugation and subsequent generation of integration-free human induced pluripotent stem cells. Peripheral blood mononuclear cells are cultured for 9 days to allow expansion of the erythroblast population. The erythroblasts are then used to derive human induced pluripotent stem cells using Sendai viral vectors, each expressing one of the four reprogramming factors Oct4, Sox2, Klf4, and c-Myc.

  6. Cell membrane softening in human breast and cervical cancer cells

    Science.gov (United States)

    Händel, Chris; Schmidt, B. U. Sebastian; Schiller, Jürgen; Dietrich, Undine; Möhn, Till; Kießling, Tobias R.; Pawlizak, Steve; Fritsch, Anatol W.; Horn, Lars-Christian; Briest, Susanne; Höckel, Michael; Zink, Mareike; Käs, Josef A.

    2015-08-01

    Biomechanical properties are key to many cellular functions such as cell division and cell motility and thus are crucial in the development and understanding of several diseases, for instance cancer. The mechanics of the cellular cytoskeleton have been extensively characterized in cells and artificial systems. The rigidity of the plasma membrane, with the exception of red blood cells, is unknown and membrane rigidity measurements only exist for vesicles composed of a few synthetic lipids. In this study, thermal fluctuations of giant plasma membrane vesicles (GPMVs) directly derived from the plasma membranes of primary breast and cervical cells, as well as breast cell lines, are analyzed. Cell blebs or GPMVs were studied via thermal membrane fluctuations and mass spectrometry. It will be shown that cancer cell membranes are significantly softer than their non-malignant counterparts. This can be attributed to a loss of fluid raft forming lipids in malignant cells. These results indicate that the reduction of membrane rigidity promotes aggressive blebbing motion in invasive cancer cells.

  7. Loss of Hfe Leads to Progression of Tumor Phenotype in Primary Retinal Pigment Epithelial Cells

    Science.gov (United States)

    Gnana-Prakasam, Jaya P.; Veeranan-Karmegam, Rajalakshmi; Coothankandaswamy, Veena; Reddy, Sushma K.; Martin, Pamela M.; Thangaraju, Muthusamy; Smith, Sylvia B.; Ganapathy, Vadivel

    2013-01-01

    Purpose. Hemochromatosis is a disorder of iron overload arising mostly from mutations in HFE. HFE is expressed in retinal pigment epithelium (RPE), and Hfe−/− mice develop age-related iron accumulation and retinal degeneration associated with RPE hyperproliferation. Here, the mechanism underlying the hyperproliferative phenotype in RPE was investigated. Methods. Cellular senescence was monitored by β-galactosidase activity. Gene expression was monitored by real-time PCR. Survivin was analyzed by Western blot and immunofluorescence. Migration and invasion were monitored using appropriate kits. Glucose transporters (GLUTs) were monitored by 3-O-methyl-D-glucose uptake. Histone deacetylases (HDACs) were studied by monitoring catalytic activity and acetylation status of histones H3/H4. Results. Hfe−/− RPE cells exhibited slower senescence rate and higher survivin expression than wild type cells. Hfe−/− cells migrated faster and showed greater glucose uptake and increased expression of GLUTs. The expression of HDACs and DNA methyltransferase (DNMTs) also was increased. Similarly, RPE cells from hemojuvelin (Hjv)-knockout mice, another model of hemochromatosis, also had increased expression of GLUTs, HDACs, and DNMTs. The expression of Slc5a8 was decreased in Hfe−/− RPE cells, but treatment with a DNA methylation inhibitor restored the transporter expression, indicating involvement of DNA methylation in the silencing of Slc5a8 in Hfe−/− cells. Conclusions. RPE cells from iron-overloaded mice exhibit several features of tumor cells: decreased senescence, enhanced migration, increased glucose uptake, and elevated levels of HDACs and DNMTs. These features are seen in Hfe−/− RPE cells as well as in Hjv−/− RPE cells, providing a molecular basis for the hyperproliferative phenotype of Hfe−/− and Hjv−/− RPE cells. PMID:23169885

  8. Fraction against Human Cancer Cell Lines

    African Journals Online (AJOL)

    fraction of A. sieberi against seven cancer cell lines (Colo20, HCT116, DLD, MCF7, Jurkat, HepG2 and ... The morphology of the HepG2 cell nucleus was investigated by Hoechst 33342, ..... Gong F, Liang Y, Xie P, Chau F. Information theory.

  9. Cardiac Progenitor Cell Extraction from Human Auricles

    KAUST Repository

    Di Nardo, Paolo; Pagliari, Francesca

    2017-01-01

    by precursor cells mostly embedded into the heart apex and in the atria. We have shown that an elective region of progenitor cell embedding is represented by the auricles, non-contractile atria appendages that can be easily sampled without harming the patient

  10. Transcriptional profiling of putative human epithelial stem cells

    Directory of Open Access Journals (Sweden)

    Koçer Salih S

    2008-07-01

    Full Text Available Abstract Background Human interfollicular epidermis is sustained by the proliferation of stem cells and their progeny, transient amplifying cells. Molecular characterization of these two cell populations is essential for better understanding of self renewal, differentiation and mechanisms of skin pathogenesis. The purpose of this study was to obtain gene expression profiles of alpha 6+/MHCI+, transient amplifying cells and alpha 6+/MHCI-, putative stem cells, and to compare them with existing data bases of gene expression profiles of hair follicle stem cells. The expression of Major Histocompatibility Complex (MHC class I, previously shown to be absent in stem cells in several tissues, and alpha 6 integrin were used to isolate MHCI positive basal cells, and MHCI low/negative basal cells. Results Transcriptional profiles of the two cell populations were determined and comparisons made with published data for hair follicle stem cell gene expression profiles. We demonstrate that presumptive interfollicular stem cells, alpha 6+/MHCI- cells, are enriched in messenger RNAs encoding surface receptors, cell adhesion molecules, extracellular matrix proteins, transcripts encoding members of IFN-alpha family proteins and components of IFN signaling, but contain lower levels of transcripts encoding proteins which take part in energy metabolism, cell cycle, ribosome biosynthesis, splicing, protein translation, degradation, DNA replication, repair, and chromosome remodeling. Furthermore, our data indicate that the cell signaling pathways Notch1 and NF-κB are downregulated/inhibited in MHC negative basal cells. Conclusion This study demonstrates that alpha 6+/MHCI- cells have additional characteristics attributed to stem cells. Moreover, the transcription profile of alpha 6+/MHCI- cells shows similarities to transcription profiles of mouse hair follicle bulge cells known to be enriched for stem cells. Collectively, our data suggests that alpha 6+/MHCI- cells

  11. DNA amplification is rare in normal human cells

    International Nuclear Information System (INIS)

    Wright, J.A.; Watt, F.M.; Hudson, D.L.; Stark, G.R.; Smith, H.S.; Hancock, M.C.

    1990-01-01

    Three types of normal human cells were selected in tissue culture with three drugs without observing a single amplification event from a total of 5 x 10 8 cells. No drug-resistant colonies were observed when normal foreskin keratinocytes were selected with N-(phosphonacetyl)-L-aspartate or with hydroxyurea or when normal mammary epithelial cells were selected with methotrexate. Some slightly resistant colonies with limited potential for growth were obtained when normal diploid fibroblast cells derived from fetal lung were selected with methotrexate or hydroxyurea but careful copy-number analysis of the dihydrofolate reductase and ribonucleotide reductase genes revealed no evidence of amplification. The rarity of DNA amplification in normal human cells contrasts strongly with the situation in tumors and in established cell lines, where amplification of onogenes and of genes mediating drug resistance is frequent. The results suggest that tumors and cell lines have acquired the abnormal ability to amplify DNA with high frequency

  12. Toona Sinensis Extracts Induced Cell Cycle Arrest and Apoptosis in the Human Lung Large Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Cheng-Yuan Wang

    2010-02-01</