The Experts below are selected from a list of 3804 Experts worldwide ranked by ideXlab platform

Fredrik Ghosh - One of the best experts on this subject based on the ideXlab platform.

  • seeing through the interface poly e caprolactone surface modification of poly glycerol co sebacic acid membranes in adult porcine Retinal explants
    Journal of Tissue Engineering and Regenerative Medicine, 2017
    Co-Authors: Linnea Taylor, Karin Arner, Martin E Kolewe, Christopher D Pritchard, Gillian Hendy, Fredrik Ghosh
    Abstract:

    The purpose of this study was to investigate the adhesion properties and tissue reactions in an in vitro model of nanofabricated membranes emulating the vitreous cortex. Electrospinning was performed for either 5, 10 or 15 min to create various thicknesses of poly(e-caprolactone) (PCL) fibre mats on a poly(glycerol-co-sebacic acid) (PGS) surface. These were fused with adult porcine Retinal explants, with the fibre side facing the inner retina, and cultured for 5 days. Adherence was assessed by macroscopic inspection, and morphological and immunohistochemical analysis was performed using haematoxylin and eosin (HE 15 min composite explants adhered only at focal points, were thin and showed extensive degenerative damage. The physical composition of nanofibre meshes is important for adhesion to the inner retina and has a significant impact on neuronal and glial survival in vitro. The results bearing on research involving Retinal Transplantation are discussed. (Less)

  • n methyl n nitrosourea induced neuronal cell death in a large animal model of Retinal degeneration in vitro
    Experimental Eye Research, 2016
    Co-Authors: Linnea Taylor, Karin Arner, Fredrik Ghosh
    Abstract:

    N-methyl-N-nitrosourea (MNU) has been reported to induce photoreceptor-specific degeneration with minimal inner Retinal impact in small animals in vivo. Pending its use within a Retinal Transplantation paradigm, we here explore the effects of MNU on outer and inner Retinal neurons and glia in an in vitro large animal model of Retinal degeneration. The previously described degenerative culture explant model of adult porcine retina was used and compared with explants receiving 10 or 100 μg/ml MNU (MNU10 and MNU100) supplementation. All explants were kept for 5 days in vitro, and examined for morphology as well as for glial and neuronal immunohistochemical markers. Rhodopsin-labeled photoreceptors were present in all explants. The number of cone photoreceptors (transducin), rod bipolar cells (PKC) and horizontal cells (calbindin) was significantly lower in MNU treated explants (p < 0.001). Gliosis was attenuated in MNU10 treated explants, with expression of vimentin, glial fibrillary protein (GFAP), glutamine synthetase (GS), and bFGF comparable to in vivo controls. In corresponding MNU100 counterparts, the expression of Muller cell proteins was almost extinguished. We here show that MNU causes degeneration of outer and inner Retinal neurons and glia in the adult porcine retina in vitro. MNU10 explants display attenuation of gliosis, despite decreased neuronal survival compared with untreated controls. Our results have impact on the use of MNU as a large animal photoreceptor degeneration model, on tissue engineering related to Retinal Transplantation, and on our understanding of gliosis related neuronal degenerative cell death.

  • selective removal of photoreceptor cells in vivo using the biodegradable elastomer poly glycerol sebacate
    Tissue Engineering Part A, 2011
    Co-Authors: Fredrik Ghosh, William L Neeley, Karin Arner, Robert Langer
    Abstract:

    Retinal Transplantation experiments have advanced considerably during recent years, but remaining diseased photoreceptor cells in the host retina physically obstruct the development of graft-host neuronal contacts which are required for vision. We here report selective removal of photoreceptors using the biodegradable elastomer poly(glycerol sebacate) (PGS). A 1x3 mm PGS membrane was implanted in the subRetinal space of normal rabbit eyes, and morphologic specimens were examined with hematoxylin and eosin staining and a panel of immunohistochemical markers. Seven days postoperatively, a patent separation of the neuroretina and Retinal pigment epithelium was found as well as loss of several rows of photoreceptors in combination with massive TUNEL staining for apoptosis in the outer nuclear layer. After 28 days, the neuroretina was reattached, the PGS membrane had degraded, and photoreceptors were absent in the implantation area. Activated Muller cells were found in the entire retina in 7-day specimens, and in the implantation area after 28 days. AII amacrine and rod bipolar cell morphology was not affected, except for disrupted dendritic branching which was present in rod bipolar cells in 28-day specimens. We conclude that Retinal detachment induced by the biodegradable PGS membrane creates a permissive environment in which graft-host neuronal connections may be facilitated in future Retinal Transplantation experiments. (Less)

Linnea Taylor - One of the best experts on this subject based on the ideXlab platform.

  • seeing through the interface poly e caprolactone surface modification of poly glycerol co sebacic acid membranes in adult porcine Retinal explants
    Journal of Tissue Engineering and Regenerative Medicine, 2017
    Co-Authors: Linnea Taylor, Karin Arner, Martin E Kolewe, Christopher D Pritchard, Gillian Hendy, Fredrik Ghosh
    Abstract:

    The purpose of this study was to investigate the adhesion properties and tissue reactions in an in vitro model of nanofabricated membranes emulating the vitreous cortex. Electrospinning was performed for either 5, 10 or 15 min to create various thicknesses of poly(e-caprolactone) (PCL) fibre mats on a poly(glycerol-co-sebacic acid) (PGS) surface. These were fused with adult porcine Retinal explants, with the fibre side facing the inner retina, and cultured for 5 days. Adherence was assessed by macroscopic inspection, and morphological and immunohistochemical analysis was performed using haematoxylin and eosin (HE 15 min composite explants adhered only at focal points, were thin and showed extensive degenerative damage. The physical composition of nanofibre meshes is important for adhesion to the inner retina and has a significant impact on neuronal and glial survival in vitro. The results bearing on research involving Retinal Transplantation are discussed. (Less)

  • n methyl n nitrosourea induced neuronal cell death in a large animal model of Retinal degeneration in vitro
    Experimental Eye Research, 2016
    Co-Authors: Linnea Taylor, Karin Arner, Fredrik Ghosh
    Abstract:

    N-methyl-N-nitrosourea (MNU) has been reported to induce photoreceptor-specific degeneration with minimal inner Retinal impact in small animals in vivo. Pending its use within a Retinal Transplantation paradigm, we here explore the effects of MNU on outer and inner Retinal neurons and glia in an in vitro large animal model of Retinal degeneration. The previously described degenerative culture explant model of adult porcine retina was used and compared with explants receiving 10 or 100 μg/ml MNU (MNU10 and MNU100) supplementation. All explants were kept for 5 days in vitro, and examined for morphology as well as for glial and neuronal immunohistochemical markers. Rhodopsin-labeled photoreceptors were present in all explants. The number of cone photoreceptors (transducin), rod bipolar cells (PKC) and horizontal cells (calbindin) was significantly lower in MNU treated explants (p < 0.001). Gliosis was attenuated in MNU10 treated explants, with expression of vimentin, glial fibrillary protein (GFAP), glutamine synthetase (GS), and bFGF comparable to in vivo controls. In corresponding MNU100 counterparts, the expression of Muller cell proteins was almost extinguished. We here show that MNU causes degeneration of outer and inner Retinal neurons and glia in the adult porcine retina in vitro. MNU10 explants display attenuation of gliosis, despite decreased neuronal survival compared with untreated controls. Our results have impact on the use of MNU as a large animal photoreceptor degeneration model, on tissue engineering related to Retinal Transplantation, and on our understanding of gliosis related neuronal degenerative cell death.

Karin Arner - One of the best experts on this subject based on the ideXlab platform.

  • seeing through the interface poly e caprolactone surface modification of poly glycerol co sebacic acid membranes in adult porcine Retinal explants
    Journal of Tissue Engineering and Regenerative Medicine, 2017
    Co-Authors: Linnea Taylor, Karin Arner, Martin E Kolewe, Christopher D Pritchard, Gillian Hendy, Fredrik Ghosh
    Abstract:

    The purpose of this study was to investigate the adhesion properties and tissue reactions in an in vitro model of nanofabricated membranes emulating the vitreous cortex. Electrospinning was performed for either 5, 10 or 15 min to create various thicknesses of poly(e-caprolactone) (PCL) fibre mats on a poly(glycerol-co-sebacic acid) (PGS) surface. These were fused with adult porcine Retinal explants, with the fibre side facing the inner retina, and cultured for 5 days. Adherence was assessed by macroscopic inspection, and morphological and immunohistochemical analysis was performed using haematoxylin and eosin (HE 15 min composite explants adhered only at focal points, were thin and showed extensive degenerative damage. The physical composition of nanofibre meshes is important for adhesion to the inner retina and has a significant impact on neuronal and glial survival in vitro. The results bearing on research involving Retinal Transplantation are discussed. (Less)

  • n methyl n nitrosourea induced neuronal cell death in a large animal model of Retinal degeneration in vitro
    Experimental Eye Research, 2016
    Co-Authors: Linnea Taylor, Karin Arner, Fredrik Ghosh
    Abstract:

    N-methyl-N-nitrosourea (MNU) has been reported to induce photoreceptor-specific degeneration with minimal inner Retinal impact in small animals in vivo. Pending its use within a Retinal Transplantation paradigm, we here explore the effects of MNU on outer and inner Retinal neurons and glia in an in vitro large animal model of Retinal degeneration. The previously described degenerative culture explant model of adult porcine retina was used and compared with explants receiving 10 or 100 μg/ml MNU (MNU10 and MNU100) supplementation. All explants were kept for 5 days in vitro, and examined for morphology as well as for glial and neuronal immunohistochemical markers. Rhodopsin-labeled photoreceptors were present in all explants. The number of cone photoreceptors (transducin), rod bipolar cells (PKC) and horizontal cells (calbindin) was significantly lower in MNU treated explants (p < 0.001). Gliosis was attenuated in MNU10 treated explants, with expression of vimentin, glial fibrillary protein (GFAP), glutamine synthetase (GS), and bFGF comparable to in vivo controls. In corresponding MNU100 counterparts, the expression of Muller cell proteins was almost extinguished. We here show that MNU causes degeneration of outer and inner Retinal neurons and glia in the adult porcine retina in vitro. MNU10 explants display attenuation of gliosis, despite decreased neuronal survival compared with untreated controls. Our results have impact on the use of MNU as a large animal photoreceptor degeneration model, on tissue engineering related to Retinal Transplantation, and on our understanding of gliosis related neuronal degenerative cell death.

  • selective removal of photoreceptor cells in vivo using the biodegradable elastomer poly glycerol sebacate
    Tissue Engineering Part A, 2011
    Co-Authors: Fredrik Ghosh, William L Neeley, Karin Arner, Robert Langer
    Abstract:

    Retinal Transplantation experiments have advanced considerably during recent years, but remaining diseased photoreceptor cells in the host retina physically obstruct the development of graft-host neuronal contacts which are required for vision. We here report selective removal of photoreceptors using the biodegradable elastomer poly(glycerol sebacate) (PGS). A 1x3 mm PGS membrane was implanted in the subRetinal space of normal rabbit eyes, and morphologic specimens were examined with hematoxylin and eosin staining and a panel of immunohistochemical markers. Seven days postoperatively, a patent separation of the neuroretina and Retinal pigment epithelium was found as well as loss of several rows of photoreceptors in combination with massive TUNEL staining for apoptosis in the outer nuclear layer. After 28 days, the neuroretina was reattached, the PGS membrane had degraded, and photoreceptors were absent in the implantation area. Activated Muller cells were found in the entire retina in 7-day specimens, and in the implantation area after 28 days. AII amacrine and rod bipolar cell morphology was not affected, except for disrupted dendritic branching which was present in rod bipolar cells in 28-day specimens. We conclude that Retinal detachment induced by the biodegradable PGS membrane creates a permissive environment in which graft-host neuronal connections may be facilitated in future Retinal Transplantation experiments. (Less)

Tian Xue - One of the best experts on this subject based on the ideXlab platform.

  • accelerated photoreceptor differentiation of hipsc derived Retinal organoids by contact co culture with Retinal pigment epithelium
    Stem Cell Research, 2019
    Co-Authors: Tasneem Akhtar, Haohuan Xie, Muhammad Imran Khan, Huan Zhao, Jin Bao, Mei Zhang, Tian Xue
    Abstract:

    Retinal organoids (ROs) derived from human-induced pluripotent stem cells recapitulate the three-dimensional structure of retina, mimic human Retinal development, and provide cell sources for pre-clinical Retinal Transplantation. Retinal pigment epithelium (RPE) is crucial for normal outer Retinal physiology, including phagocytosis of shed photoreceptor outer segments and secretion of neurotrophic and vasculotrophic growth factors. However, whether ROs-RPE co-culture can improve the differentiation of photoreceptors in ROs in vitro remains unknown. Herein, primary mouse RPE cells were contact co-cultured with ROs at different time points. Our results revealed that the RPE cells accelerated photoreceptor differentiation in ROs, as the cross talk between the RPE and ROs promoted the stage specific expression of photoreceptor markers at different differentiation stages. Thus, we established an improved co-culture system based on modeling of human retina-RPE dynamics during retinogenesis for the evaluation of ocular therapies.

Martin E Kolewe - One of the best experts on this subject based on the ideXlab platform.

  • seeing through the interface poly e caprolactone surface modification of poly glycerol co sebacic acid membranes in adult porcine Retinal explants
    Journal of Tissue Engineering and Regenerative Medicine, 2017
    Co-Authors: Linnea Taylor, Karin Arner, Martin E Kolewe, Christopher D Pritchard, Gillian Hendy, Fredrik Ghosh
    Abstract:

    The purpose of this study was to investigate the adhesion properties and tissue reactions in an in vitro model of nanofabricated membranes emulating the vitreous cortex. Electrospinning was performed for either 5, 10 or 15 min to create various thicknesses of poly(e-caprolactone) (PCL) fibre mats on a poly(glycerol-co-sebacic acid) (PGS) surface. These were fused with adult porcine Retinal explants, with the fibre side facing the inner retina, and cultured for 5 days. Adherence was assessed by macroscopic inspection, and morphological and immunohistochemical analysis was performed using haematoxylin and eosin (HE 15 min composite explants adhered only at focal points, were thin and showed extensive degenerative damage. The physical composition of nanofibre meshes is important for adhesion to the inner retina and has a significant impact on neuronal and glial survival in vitro. The results bearing on research involving Retinal Transplantation are discussed. (Less)