We wish to thank the following individuals: Drs. Tim Krohne and Eyal Banin (along with Dr. Mandy Lehmann and David Friedlander) for generous help developing the differentiation protocols. Dr. Felicitas Bucher provided assistance differentiating the RPE cells used in this study. We also acknowledge the National Eye Institute (NEI grants EY11254 and EY021416), California Institute for Regenerative Medicine (CIRM grant TR1-01219), and the Lowy Medical Research Institute (LMRI) for very generous funding for this project.

1. differenziazione Regia di Stem Cell-RPE derivati NOTA: Tutte le fasi di incubazione sono eseguite a 37 ° C in 5% CO 2 <ol style="margin-left: 40px;"><li> Mantenere le linee hES o anche (sfamare giorno) in mezzi di manutenzione (MM; Tabella 1). Una volta che le linee hanno raggiunto un livello sufficiente di controllo della qualità, li mantengono su uno strato di cellule feeder embrionali di topo (MEF) seminate ad una densità di 250.000 / pozzetto di una piastra ben sei. Culture senza Xeno possono anche essere generati seguendo il protocollo stabilito dalla Tucker et al. 40. </li><li> Lasciare le colonie di cellule staminali per raggiungere confluenza. </li><li> Passare ai media differenziazione Nicotinamide (DM / NIC, tabella 1); alimentare quotidiano. </li><li> Dopo tre settimane di cultura, passare a mezzi di differenziazione con nicotinamide e sia Activin-A o IDE-1 (DM / NIC / AA o DM / NIC / IDE1; Tabella 1) per migliorare la differenziazione RPE. </li&gt; <li> Dopo cinque settimane di cultura, tornare a DM / NIC. Poppate giornaliere non sono più necessarie, una volta gli indicatori di pH nei fermata supporto girando giallo il giorno dopo la poppata. </li><li> Attendere isolotti di cellule pigmentate a comparire che sono abbastanza grandi per essere tagliato e rimosso (vedi figure 2D-F e 3A). </li></ol> 2. isolanti pigmentate Islets <ol style="margin-left: 40px;"><li> Rivestire le pozzetti di una piastra da 24 pozzetti con una matrice che simula l&#39;ambiente naturale delle cellule (senza xeno è preferibile). NOTA: le lame affilate, cornea e pinze dalla punta sottile sono molto utili per la raccolta. L&#39;intero foglio di cellule differenziate possono staccarsi mentre la raccolta. Evitare questo lavorando con attenzione e inizialmente raccolta colonie nel centro del piatto. </li><li> Riempire altrettanti pozzetti della piastra 24 pozzetti con i media differenziazione (DM; Tabella 1) come necessario. Questa decisione dipenderà dal numero di colonie pigmentateraccolti. </li><li> In una cappa di coltura cellulare con un ambito dissezione, tagliate manualmente isolotti pigmentate. Tritare ogni isolotto sul fondo del piatto originale utilizzando un bisturi in circa 2-6 pezzi e afferrare le parti pigmentate con pinze taglienti. </li><li> Trasferire 1-2 pezzi pigmentate in ogni 24 pozzetti. </li><li> Non modificare i media per 3-5 giorni fino cellule aderiscono, quindi iniziare a cambiare i media tre volte a settimana. (Se non aderiscono dopo questo tempo, la probabilità è bene che non lo farà mai). </li><li> Espandere le cellule per 3-4 settimane a supporto di differenziazione (DM; Tabella 1) - L&#39;immagine di una cultura tipica è mostrato in figura 3B. Le cellule non possono ancora riempire tutto bene, ma aspettare più a lungo non sembra aiutare. Concime cellule tre volte alla settimana. </li><li> Dopo circa 3 settimane, rimuovere manualmente gruppi di globuli bianchi in gruppi, se necessario, con una pinza taglienti. Non fare questo passo se non è necessario - è facile introdurre contaminanti. E &#39;ideale percercare di ottenere più pure popolazioni RPE dalle colonie pigmentate originali al punto 1.6. </li></ol> RPE 3. Passaging Stem-Cell derivati <ol style="margin-left: 40px;"><li> Staccare cellule con 200 microlitri con una soluzione di dissociazione cellulare (preferibilmente non tripsina-un reagente che può essere inattivato mediante diluizione è preferibile) per 5-8 minuti a 37 ° C, e inattivare esso diluendo con DM. Utilizzare una pipetta 200 microlitri per lavare via tutte le cellule e risospendere loro (Se il pozzetto selezionato contiene solo poche cellule, prendere in considerazione la messa in comune le cellule da due 24 pozzetti). </li><li> Centrifuga (800 xg per 5 minuti), scartare il surnatante e risospendere in 3 ml DM media. </li><li> Cellule Re-piastra da uno (o due) 24 pozzetti in una matrice rivestite 6 pozzetti in 3 ml di DM per pozzetto (1: 5 di espansione). </li><li> Espandere per 1-2 settimane, fino a quando le cellule sono ~ 90% confluenti; l&#39;immagine di coltura pura completamente differenziata è mostrato in Figura 3C. </li><li> Staccare le cellule con 1 ml di cellule dSoluzione issociation per circa 5-8 minuti a 37 ° C, inattivare dal diluizione con DM, utilizzare 1.000 microlitri pipetta per lavare via tutte le cellule, e risospendere. </li><li> Spin down (800 xg per 5 minuti), scartare il surnatante e risospendere in 18 ml DM media. </li><li> Cellule Re-piastra da 6 pozzetti uno ciascuno in sei matrice 6-pozzetti rivestiti in 3 ml di DM per pozzetto (1: 6 espansione) o uno rivestite 75 centimetri 2 beuta (1: 7,5 espansione). </li><li> Ripetere i passaggi 3,4-3,8 necessaria fino a quando si ottengono abbastanza cellule. NOTA: cercare di raccogliere il maggior numero possibile di colonie di espansione piuttosto che la pianificazione di amplificare le culture attraverso passaging poiché ogni passaggio induce RPE dedifferentiation. </li></ol>

<ol>
	<li>Strauss, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+retinal+pigment+epithelium+in+visual+function.">The retinal pigment epithelium in visual function.</a> Physiol Rev. 85 (3), 845-881 (2005).</li><li>Congdon, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Causes+and+prevalence+of+visual+impairment+among+adults+in+the+United+States.">Causes and prevalence of visual impairment among adults in the United States.</a> Arch Ophthalmol. 122 (4), 477-485 (2004).</li><li>Friedman, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prevalence+of+age-related+macular+degeneration+in+the+United+States.">Prevalence of age-related macular degeneration in the United States.</a> Arch Ophthalmol. 122 (4), 564-572 (2004).</li><li>Resnikoff, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+data+on+visual+impairment+in+the+year.">Global data on visual impairment in the year.</a> Bull World Health Organ. 82 (11), 844-851 (2002).</li><li>Bird, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Therapeutic+targets+in+age-related+macular+disease.">Therapeutic targets in age-related macular disease.</a> The Journal of Clinical Investigation. 120 (9), 3033-3041 (2010).</li><li>Jong, P. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age-related+macular+degeneration.">Age-related macular degeneration.</a> N Engl J Med. 355 (14), 1474-1485 (2006).</li><li>Binder, S., Stanzel, B. V., Krebs, I., Glittenberg, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Progress+In+Retinal+And+Eye+Research.">Progress In Retinal And Eye Research.</a> Transplantation of the RPE in AMD. 26 (5), 516-554 (2007).</li><li>Cruz, L., Chen, F. K., Ahmado, A., Greenwood, J., Coffey, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RPE+transplantation+and+its+role+in+retinal+disease.">RPE transplantation and its role in retinal disease.</a> Progress In Retinal And Eye Research. 26 (6), 598-635 (2007).</li><li>Carr, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protective+effects+of+human+iPS-derived+retinal+pigment+epithelium+cell+transplantation+in+the+retinal+dystrophic+rat.">Protective effects of human iPS-derived retinal pigment epithelium cell transplantation in the retinal dystrophic rat.</a> PLoS One. 4 (12), e8152 (2009).</li><li>Idelson, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Directed+differentiation+of+human+embryonic+stem+cells+into+functional+retinal+pigment+epithelium+cells.">Directed differentiation of human embryonic stem cells into functional retinal pigment epithelium cells.</a> Cell Stem Cell. 5 (4), 396-408 (2009).</li><li>Klimanskaya, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Derivation+and+comparative+assessment+of+retinal+pigment+epithelium+from+human+embryonic+stem+cells+using+transcriptomics.">Derivation and comparative assessment of retinal pigment epithelium from human embryonic stem cells using transcriptomics.</a> Cloning Stem Cells. 6 (3), 217-245 (2004).</li><li>Krohne, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+retinal+pigment+epithelial+cells+from+small+molecules+and+OCT4-reprogrammed+human+induced+pluripotent+stem+cells.">Generation of retinal pigment epithelial cells from small molecules and OCT4-reprogrammed human induced pluripotent stem cells.</a> Stem Cells Translational Medicine. 1 (2), 96-109 (2012).</li><li>Lund, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+embryonic+stem+cell-derived+cells+rescue+visual+function+in+dystrophic+RCS+rats.">Human embryonic stem cell-derived cells rescue visual function in dystrophic RCS rats.</a> Cloning Stem Cells. 8, 189-199 (2006).</li><li>Vugler, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Elucidating+the+phenomenon+of+HESC-derived+RPE:+anatomy+of+cell+genesis,+expansion+and+retinal+transplantation.">Elucidating the phenomenon of HESC-derived RPE: anatomy of cell genesis, expansion and retinal transplantation.</a> Exp Neurol. 214 (2), 347-361 (2008).</li><li>Algvere, P. V., Berglin, L., Gouras, P., Sheng, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantation+of+fetal+retinal+pigment+epithelium+in+age-related+macular+degeneration+with+subfoveal+neovascularization.">Transplantation of fetal retinal pigment epithelium in age-related macular degeneration with subfoveal neovascularization.</a> Graefes Arch Clin Exp Ophthalmol. 232 (12 ), 707-716 (1994).</li><li>Binder, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Outcome+of+transplantation+of+autologous+retinal+pigment+epithelium+in+age-related+macular+degeneration:+a+prospective+trial.">Outcome of transplantation of autologous retinal pigment epithelium in age-related macular degeneration: a prospective trial.</a> Invest Ophthalmol Vis Sci. 45 (11), 4151-4160 (2004).</li><li>Binder, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantation+of+autologous+retinal+pigment+epithelium+in+eyes+with+foveal+neovascularization+resulting+from+age-related+macular+degeneration:+a+pilot+study.">Transplantation of autologous retinal pigment epithelium in eyes with foveal neovascularization resulting from age-related macular degeneration: a pilot study.</a> Am J Ophthalmol. 133 (2), 215-225 (2002).</li><li>Falkner-Radler, C. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+retinal+pigment+epithelium+(RPE)+transplantation:+outcome+after+autologous+RPE-choroid+sheet+and+RPE+cell-suspension+in+a+randomised+clinical+study.">Human retinal pigment epithelium (RPE) transplantation: outcome after autologous RPE-choroid sheet and RPE cell-suspension in a randomised clinical study.</a> British Journal of Ophthalmology. 95 (3), 370-375 (2011).</li><li>Li, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+safety+and+efficacy+of+human-induced+pluripotent+stem+cell+(iPS)+grafts+in+a+preclinical+model+of+retinitis+pigmentosa.">Long-term safety and efficacy of human-induced pluripotent stem cell (iPS) grafts in a preclinical model of retinitis pigmentosa.</a> Molecular Medicine (Cambridge, Mass). 18, 1312-1319 (2012).</li><li>Lu, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-Term+Safety+and+Function+of+RPE+from+Human+Embryonic+Stem+Cells+in+Preclinical+Models+of+Macular+Degeneration).">Long-Term Safety and Function of RPE from Human Embryonic Stem Cells in Preclinical Models of Macular Degeneration).</a> Stem Cells. 27 (9), 2126-2135 (2009).</li><li>Peyman, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+technique+for+retinal+pigment+epithelium+transplantation+for+age-related+macular+degeneration+secondary+to+extensive+subfoveal+scarring.">A technique for retinal pigment epithelium transplantation for age-related macular degeneration secondary to extensive subfoveal scarring.</a> Ophthalmic Surgery. 22 (2), 102-108 (1991).</li><li>Schwartz, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Embryonic+stem+cell+trials+for+macular+degeneration:+a+preliminary+report.">Embryonic stem cell trials for macular degeneration: a preliminary report.</a> The Lancet. 379 (9817), 713-720 (2012).</li><li>Wang, N. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantation+of+reprogrammed+embryonic+stem+cells+improves+visual+function+in+a+mouse+model+for+retinitis+pigmentosa.">Transplantation of reprogrammed embryonic stem cells improves visual function in a mouse model for retinitis pigmentosa.</a> Transplantation. 89 (8), 911-919 (2010).</li><li>Cruz, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mutation+of+the+receptor+tyrosine+kinase+gene+Mertk+in+the+retinal+dystrophic+RCS+rat.">Mutation of the receptor tyrosine kinase gene Mertk in the retinal dystrophic RCS rat.</a> Human Molecular Genetics. 9 (4), 645-651 (2000).</li><li>Buchholz, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Derivation+of+functional+retinal+pigmented+epithelium+from+induced+pluripotent+stem+cells.">Derivation of functional retinal pigmented epithelium from induced pluripotent stem cells.</a> Stem Cells. 27 (10), 2427-2434 (2009).</li><li>Hirami, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+retinal+cells+from+mouse+and+human+induced+pluripotent+stem+cells.">Generation of retinal cells from mouse and human induced pluripotent stem cells.</a> Neurosci Lett. 458 (3), 126-131 (2009).</li><li>Meyer, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modeling+early+retinal+development+with+human+embryonic+and+induced+pluripotent+stem+cells.">Modeling early retinal development with human embryonic and induced pluripotent stem cells.</a> Proceedings of the National Academy of Sciences. 106 (39), 16698-16703 (2009).</li><li>Osakada, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+differentiation+of+retinal+cells+from+human+pluripotent+stem+cells+by+small-molecule+induction.">In vitro differentiation of retinal cells from human pluripotent stem cells by small-molecule induction.</a> J Cell Sci. 122 (17), 3169-3179 (2009).</li><li>Carr, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+characterization+and+functional+analysis+of+phagocytosis+by+human+embryonic+stem+cell-derived+RPE+cells+using+a+novel+human+retinal+assay.">Molecular characterization and functional analysis of phagocytosis by human embryonic stem cell-derived RPE cells using a novel human retinal assay.</a> Mol Vis. 15, 283-295 (2009).</li><li>Kokkinaki, M., Sahibzada, N., Golestaneh, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+Induced+Pluripotent+Stem-Derived+Retinal+Pigment+Epithelium+(RPE)+Cells+Exhibit+Ion+Transport,+Membrane+Potential,+Polarized+Vascular+Endothelial+Growth+Factor+Secretion,+and+Gene+Expression+Pattern+Similar+to+Native+RPE.">Human Induced Pluripotent Stem-Derived Retinal Pigment Epithelium (RPE) Cells Exhibit Ion Transport, Membrane Potential, Polarized Vascular Endothelial Growth Factor Secretion, and Gene Expression Pattern Similar to Native RPE.</a> Stem Cells. 29 (5), 825-835 (2011).</li><li>Westenskow, P., Friedlander, M., Werne, J. S., Chalupa, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ch.+111.">Ch. 111.</a> The New Visual Neurosciences. , 1611-1626 (2013).</li><li>Westenskow, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+flow+cytometry+to+compare+the+dynamics+of+photoreceptor+outer+segment+phagocytosis+in+iPS-derived+RPE+cells.">Using flow cytometry to compare the dynamics of photoreceptor outer segment phagocytosis in iPS-derived RPE cells.</a> Invest Ophthalmol Vis Sci. 53 (10), 6282-6290 (2012).</li><li>Algvere, P. V., Gouras, P., Dafgard Kopp, ., E, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+outcome+of+RPE+allografts+in+non-immunosuppressed+patients+with+AMD.">Long-term outcome of RPE allografts in non-immunosuppressed patients with AMD.</a> Eur J Ophthalmol. 9 (3), 217-230 (1999).</li><li>Zhang, X., Bok, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantation+of+retinal+pigment+epithelial+cells+and+immune+response+in+the+subretinal+space.">Transplantation of retinal pigment epithelial cells and immune response in the subretinal space.</a> Invest Ophthalmol Vis Sci. 39 (6), 1021-1027 (1998).</li><li>Gamm, D. M., Phillips, M. J., Singh, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modeling+retinal+degenerative+diseases+with+human+iPS-derived+cells:+current+status+and+future+implications.">Modeling retinal degenerative diseases with human iPS-derived cells: current status and future implications.</a> Expert Review Of Ophthalmology. 8, 213-216 (2013).</li><li>Singh, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=iPS+cell+modeling+of+Best+disease:+insights+into+the+pathophysiology+of+an+inherited+macular+degeneration.">iPS cell modeling of Best disease: insights into the pathophysiology of an inherited macular degeneration.</a> Hum Mol Genet. 22 (3), 593-607 (2013).</li><li>Buchholz, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+and+efficient+directed+differentiation+of+human+pluripotent+stem+cells+into+retinal+pigmented+epithelium.">Rapid and efficient directed differentiation of human pluripotent stem cells into retinal pigmented epithelium.</a> Stem Cells Transl Med. 2 (5), 384-393 (2013).</li><li>Fuhrmann, S., Levine, E. M., Reh, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extraocular+mesenchyme+patterns+the+optic+vesicle+during+early+eye+development+in+the+embryonic+chick.">Extraocular mesenchyme patterns the optic vesicle during early eye development in the embryonic chick.</a> Development (Cambridge, England). 127 (21), 4599-4609 (2000).</li><li>Borowiak, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Small+molecules+efficiently+direct+endodermal+differentiation+of+mouse+and+human+embryonic+stem+cells.">Small molecules efficiently direct endodermal differentiation of mouse and human embryonic stem cells.</a> Cell Stem Cell. 4 (4), 348-358 (2009).</li><li>Tucker, B. A., Anfinson, K. R., Mullins, R. F., Stone, E. M., Young, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+a+synthetic+xeno-free+culture+substrate+for+induced+pluripotent+stem+cell+induction+and+retinal+differentiation.">Use of a synthetic xeno-free culture substrate for induced pluripotent stem cell induction and retinal differentiation.</a> Stem Cells Transl Med. 2 (1), 16-24 (2013).</li><li>Ramsden, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stem+cells+in+retinal+regeneration:+past,+present+and+future.">Stem cells in retinal regeneration: past, present and future.</a> Development (Cambridge, England). 140 (12), 2576-2585 (2013).</li><li>Zhao, T., Zhang, Z. -. N., Rong, Z., Xu, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunogenicity+of+induced+pluripotent+stem+cells.">Immunogenicity of induced pluripotent stem cells.</a> Nature. 474 (7350), 212-215 (2011).</li><li>Zhang, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+conversion+of+human+fibroblasts+into+retinal+pigment+epithelium-like+cells+by+defined+factors.">Direct conversion of human fibroblasts into retinal pigment epithelium-like cells by defined factors.</a> Protei., &amp; Cell. 5 (1), 48-58 (2013).</li></ol>

None of the authors have any commercial disclosures to declare.

In questo manoscritto abbiamo delineare i passi per generare in modo efficiente grandi quantità di culture iPS-RPE puri. Abbiamo dimostrato in precedenza con questo protocollo di differenziazione diretto con Activin A che possiamo generare iPS-RPE che assomigliano fortemente hRPE base di trascrittomica, proteomica, metabolomica, e funzionalità, e che ritardare la degenerazione retinica quando impiantato in ratti RCS 12,31,32 . Il processo di generazione IPS-RPE richiede molto tempo, ma non laboriosa <strong...

The various cell types that occupy the retina are organized in a functional architecture. The photoreceptors in the back of the retina are responsible for converting light into electrical impulses through phototransduction. However, phototransduction cannot occur without the coordinated efforts of other neighboring cell types including Mueller glia and retinal pigment epithelium (RPE) cells. A monolayer of RPE cells partitions the sensory retina from the choriocapillaris, the primary blood supply for photoreceptors, and are ideally situated to control multiple functions important for photoreceptor homeostasis. In fact, the RPE and photoreceptors are so co-dependent they are widely considered to be one single functional unit. (For a review of all the diverse functions of the RPE see Strauss, 20051.) Death or dysfunction of retinal pigment epithelium cells can induce age-related macular degeneration (AMD), the leading cause of permanent vision loss in industrialized countries2-4. 
AMD is a multifactorial disease of RPE, photoreceptors, and the choroidal vasculature; risk factors are diverse and include combinations of environmental and genetic influences5,6. Treatments for AMD are very limited, but one promising potential therapy is RPE cell replacement7,8. While the outcomes have been mixed, the transplantation of RPE cells in AMD patients (and in other patients with retinal degeneration) and also in rodent models of retinal degeneration, has the potential to transiently prevent significant photoreceptor atrophy9-23. (The animal model commonly used for these studies are Royal College of Surgeons (RCS) rats, which harbor a mutation in the MerTK gene. This mutation renders RPE cells incapable of phagocytosing photoreceptor outer segments and promotes retinal degeneration24.) While the reported survival rates of implanted RPE in the subretinal space of RCS rats and mice vary greatly, there is potential for them to survive for several months or years9,10,12,20. 
RPE cells can be obtained in sufficient numbers for transplantation by deriving them from pluripotent stem cells9-14,25-28. Several independent groups have demonstrated that these cells function in similar ways to their somatic counterparts, and long term studies suggest that they are safe upon implantation in rat and mouse disease models9,10,12,14,19,20,25,29-32. The use of induced pluripotent stem cells instead of embryonic stem cells may be advantageous since ethical issues and immunological challenges associated with allogeneic RPE may be obviated33,34. Another exciting application for iPS technology is disease modeling35. The ability to interrogate large numbers of RPE cells derived from patients with RPE diseases could be invaluable for understanding their molecular bases. This type of study has been performed recently with Best disease patient RPE and could pave the way for similar studies of inherited maculopathies36. 
The derivation of RPE from stem cells is a relatively simple process and can be done entirely in xeno-free conditions. The simplest strategy is to derive monolayers of RPE cells spontaneously, however, the yield can be significantly improved using directed differentiation techniques. But these techniques involve the use of exogenous protein factors that can be expensive and often generated in bacteria or other non-human sources10,12,37. In our studies we followed an established protocol10 that utilizes nicotinamide and Activin A, a signaling factor that has been shown to be sufficient for RPE specification38. Here we will demonstrate that the small molecule IDE-1 can adequately replace Activin A, thus reducing costs and alleviating concerns associated with the use of recombinant proteins39. Additionally, we utilize xeno-free serum replacement, and we culture the differentiating RPE cells on a synthetic xeno-free substrate. RPE cells have been shown previously to differentiate very effectively using this approach40.
When differentiated as a monolayer, we visualize pigmented colonies containing RPE cells after as early as five weeks12. Once they reach sufficient size, they can be manually excised and transferred to another dish for expansion. RPE cells are notorious for dedifferentiating with each passage, and the use of anything older than five passages should be avoided (we find that sufficient numbers of cells for characterization and transplantation in animal models can easily be generated after two or three passages). Once fully differentiated, we employ multiple techniques to characterize the cells anatomically and functionally to ensure that they will serve as adequate replacements for diseased RPE. The description of these techniques, and protocol for implanting the iPS-RPE in the subretinal space of rodents, are beyond the scope of this methods paper and have been previously published12,32,41. 
While developing standardized protocols for effective derivation of iPS-RPE is clearly important for the clinics, there is also significant preclinical work to still be done in animal models. There are concerns regarding immunogenicity of iPS-derived cells, and multiple different implantation techniques, including implanting cells on artificial substrates, are being explored42,43. For these reasons, we feel that the publication of standardized protocols is beneficial to facilitate both clinical and preclinical studies. Especially if direct comparisons will be done of iPS-RPE cells derived in different labs by different research groups.

<table border="0" cellpadding="0" cellspacing="0" width="849">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Name of Material/ Equipment (A-Z)</td>
			<td style="width:145px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Corneal knife&#160;</td>
			<td style="width:145px;">Surgipro</td>
			<td style="width:119px;">SPOI-070</td>
			<td>knife x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">DMEM/F-12, HEPES</td>
			<td style="width:145px;">Life Technologies</td>
			<td>11330-032</td>
			<td>500 mL x 4&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dulbecco&#39;s Phosphate-Buffered Saline, 1X w/out Ca or Mg</td>
			<td style="width:145px;">VWR</td>
			<td style="width:119px;">45000-434</td>
			<td>500 mL x 6</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Fetal Bovine Serum, Regular (Heat Inactivated)</td>
			<td style="width:145px;">VWR</td>
			<td style="width:119px;">45000-736</td>
			<td>500 mL x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">FGF-Basic (AA 10-155) Recombinant Human Protein</td>
			<td style="width:145px;">Life Technologies</td>
			<td style="width:119px;">PHG0021</td>
			<td>100 ug x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">IDE-1</td>
			<td style="width:145px;">Stemgent</td>
			<td style="width:119px;">04-0026</td>
			<td>2 mg x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Knockout DMEM</td>
			<td style="width:145px;">Life Technologies</td>
			<td style="width:119px;">10829-018</td>
			<td>500 mL x 1&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">KnockOut Serum Replacement</td>
			<td style="width:145px;">Life Technologies</td>
			<td style="width:119px;">10828-028</td>
			<td>500 mL x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">L-Glutamine 200 mM&#160;</td>
			<td style="width:145px;">Life Technologies</td>
			<td style="width:119px;">25030-081</td>
			<td>100 mL x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">MEM Non-Essential Amino Acids Solution 100X&#160;</td>
			<td style="width:145px;">Life Technologies</td>
			<td style="width:119px;">11140-050</td>
			<td>100 mL x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Nicotinamide</td>
			<td style="width:145px;">Sigma-Aldrich</td>
			<td style="width:119px;">N0636-100G</td>
			<td>100 g x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Penicillin-Streptomycin (10,000 U/mL)</td>
			<td style="width:145px;">Life Technologies</td>
			<td style="width:119px;">15140-148</td>
			<td>20 mL x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Recombinant Human/Murine/Rat Activin A&#160;</td>
			<td style="width:145px;">PeproTech</td>
			<td style="width:119px;">120-14E</td>
			<td>10 ug x 2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Synthemax-T Surface 6 Well Plates</td>
			<td style="width:145px;">Corning</td>
			<td style="width:119px;">3877</td>
			<td>Case(12) x 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">TrypLE-Express Enzyme (1X), no phenol red&#160;</td>
			<td style="width:145px;">Life Technologies</td>
			<td style="width:119px;">12604-021</td>
			<td>500 mL x 1&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:419px;">Vacuum Filter/Storage Bottle System, 0.1&#181;m pore, 500mL&#160;</td>
			<td style="width:145px;">Corning</td>
			<td style="width:119px;">431475</td>
			<td>Case(12) x 1&#160;</td>
		</tr>
	</tbody>
</table>

efficient derivation of retinal pigment epithelium cells from stem cells

No cure has been discovered for age-related macular degeneration (AMD), the leading cause of vision loss in people over the age of 55. AMD is complex multifactorial disease with an unknown etiology, although it is largely thought to occur due to death or dysfunction of the retinal pigment epithelium (RPE), a monolayer of cells that underlies the retina and provides critical support for photoreceptors. RPE cell replacement strategies may hold great promise for providing therapeutic relief for a large subset of AMD patients, and RPE cells that strongly resemble primary human cells (hRPE) have been generated in multiple independent labs, including our own. In addition, the uses for iPS-RPE are not limited to cell-based therapies, but also have been used to model RPE diseases. These types of studies may not only elucidate the molecular bases of the diseases, but also serve as invaluable tools for developing and testing novel drugs. We present here an optimized protocol for directed differentiation of RPE from stem cells. Adding nicotinamide and either Activin A or IDE-1, a small molecule that mimics its effects, at specific time points, greatly enhances the yield of RPE cells. Using this technique we can derive large numbers of low passage RPE in as early as three months.

La procedura descritta in questo manoscritto, come illustrato nella figura 1, possono essere utilizzati per generare facilmente RPE da cellule staminali come precedentemente riportato 10,12. Dopo aver mantenuto le linee iPS per diverse settimane, colonie pigmentate cominciano ad apparire nelle colonie dopo 5-7 settimane (7 settimane vecchie culture sono mostrati in figura 2A-C). Queste colonie possono continuare a crescere per settimane come le culture sono mantenuti. Una vol...

Watch this Scientific Journal Video about Efficient Derivation of Retinal Pigment Epithelium Cells from Stem Cells at JoVE.com

Efficient Derivation of Retinal Pigment Epithelium Cells from Stem Cells

Stem cell-derived retinal pigment epithelium (RPE) cells may be used for multiple applications including cell-based therapies for retinal degeneration, disease modeling, and drug studies. Here we present a simple protocol for reproducibly deriving RPE from stem cells.

Derivazione efficiente di cellule retiniche epitelio pigmentato da cellule staminali

No cure has been discovered for age-related macular degeneration  (AMD), the leading cause of vision loss in people over the age of 55. AMD is complex ...

efficient-derivation-retinal-pigment-epithelium-cells-from-stem

Research

JoVE Journal

Developmental Biology

9.1K Views.  The Scripps Research Institute. Stem cell-derived retinal pigment epithelium (RPE) cells may be used for multiple applications including cell-based therapies for retinal degeneration, disease modeling, and drug studies. Here we present a simple protocol for reproducibly deriving RPE from stem cells.