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Towards Photoreceptor Replacement in the Mammalian Retina – Identification of Factors Influencing Donor Cell Integration

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Towards Photoreceptor Replacement in the Mammalian Retina – Identification of Factors Influencing Donor Cell Integration Towards Photoreceptor Replacement in the Mammalian Retina – Identification of Factors Influencing Donor Cell Integration DISSERTATION zur Erlangung des akademischen Grades Doctor rerum naturalium (Dr. rer. nat.) vorgelegt der Fakultät Mathematik und Naturwissenschaften der Technischen Universität Dresden von Dipl. - Biol. Kai Postel geboren am 23.06.1984 in Dresden Eingereicht am 07.02.2014 Die Dissertation wurde in der Zeit von 10 / 2009 bis 02 / 2014 im Zentrum für Regenerative Therapien Dresden (CRTD) angefertigt Gutachter: Prof. Elly Tanaka, Prof. Gilbert Weidinger Datum der Verteidigung: 28.04.2014 Table of Contents Acknowledgment ...................................................................................................................... IV List of figures ............................................................................................................................ VI List of tables ............................................................................................................................. VII Abbreviations .......................................................................................................................... VIII Abstract ....................................................................................................................................... 1 Zusammenfassung ..................................................................................................................... 3 1 Introduction .......................................................................................................................... 5 1.1 Gross anatomy of the eye and the retina ....................................................................... 6 1.2 Retinal cell types ............................................................................................................ 8 1.2.1 Photoreceptors and RPE cells ................................................................................ 8 1.2.2 Second order neurons and ganglion cells ............................................................. 12 1.2.3 Non-neuronal cell types ......................................................................................... 13 1.3 Retinal degenerative diseases ..................................................................................... 14 1.4 Therapeutic approaches for retinal degenerations ....................................................... 15 1.5 Photoreceptor replacement – state of the art ............................................................... 16 1.6 Aim of the study ............................................................................................................ 20 2 Identification of rod specific surface proteins and CD73-mediated photoreceptor enrichment ................................................................................................................................. 21 2.1 Introduction ................................................................................................................... 22 2.2 Results .......................................................................................................................... 22 2.2.1 Cell sorting and microarray ................................................................................... 22 2.2.2 Microarray data analysis ....................................................................................... 25 2.2.3 CD73-mediated photoreceptor enrichment and transplantation ............................ 31 2.3 Discussion .................................................................................................................... 34 3 Reactive gliosis and enlarged subretinal graft distribution improve integration rates of transplanted photoreceptor precursors ............................................................................. 38 3.1 Introduction ................................................................................................................... 39 3.2 Results .......................................................................................................................... 40 3.2.1 Transplantation of photoreceptor precursors into aging mice ............................... 40 3.2.2 Increased integration of rod photoreceptors into Nrl-/- mice ................................... 42 3.2.3 Müller glia activation permits donor photoreceptor integration .............................. 44 3.2.4 Increased area coverage by donor photoreceptors in Nrl-/- host retinae ............... 46 3.3 Discussion .................................................................................................................... 48 II 4 Transplantation of enriched rat photoreceptors into mice and rats ............................. 51 4.1 Introduction ................................................................................................................... 52 4.2 Results .......................................................................................................................... 54 4.2.1 MAC-sorting of rat cells ......................................................................................... 54 4.2.2 Transplantation of enriched rat photoreceptors into mouse and rat recipients...... 56 4.3 Discussion .................................................................................................................... 59 5 Conclusion and future perspectives ................................................................................ 62 6 Material and Methods ........................................................................................................ 65 6.1 Animals ......................................................................................................................... 66 6.2 Cell preparation, flow cytometry and RNA isolation ..................................................... 67 6.3 Microarray and data analysis ........................................................................................ 67 6.4 RNA isolation and RT-PCR for tissue distribution analysis .......................................... 68 6.5 Eye preparation and cryosectioning ............................................................................. 68 6.6 Probe design and in situ hybridization .......................................................................... 69 6.7 Cell isolation and MACS of mouse and rat photoreceptors .......................................... 70 6.8 Transplantation ............................................................................................................. 71 6.9 Flat-mounting of retinae ................................................................................................ 71 6.10 Staining of sectioned and flat-mounted retinae ............................................................ 72 6.11 EdU labeling ................................................................................................................. 73 6.12 Quantification, image processing and statistics ............................................................ 74 7 Bibliography ....................................................................................................................... 75 8 Appendices ........................................................................................................................ 85 8.1 Supplementary table 1: DAVID-enriched gene list ....................................................... 86 8.2 Supplementary table 2: Primer list ................................................................................ 89 8.3 Erklärung entsprechend §5.5 der Promotionsordnung ................................................. 90 III Acknowledgment I like to mention all people who supported me during the last four years in various ways and enabled me to summarize this period in the present thesis. First of all, I like to thank my supervisor Dr. Marius Ader for his great support during the whole time. Thank you, for being patient with my bad luck at the beginning, for providing ideas, giving me motivation and initiating my fascination for our topic. And thank you very much for having your door as well as your ears always open for sorrows, ideas or even discussions about Kiss. I also would like to acknowledge all present and former members of the Ader group (CRTD, Dresden), including Jochen, Sandra, Oliver, Madalena, Magda, Aga, Dominic, Daniela, Praveen, Alex (and the people that I forgot) for the nice time in the lab, the lunch breaks, our fruitful lab meetings and conversations and our nice lab trips. Especially I like to thank Tiago Santos-Ferreira (CRTD, Dresden, Ader group) for our great collaboration, the nice time that we spent transplanting in the mouse room, playing table tennis, eating Roggenvollkornbrötchen and for being an endless source of motivation and ideas. I am grateful for the cooperation with Victoria Splith (CRTD, Dresden) and Jessica Bellmann (CRTD, Dresden), conducting experiments under my supervision and helping me to publish my primary first-author paper. Additionally, I would like to mention David (MTZ, Dresden) and Jule (MTZ, Dresden) and thank them for our memorable lunch-club sessions and discussions related to very special scientific issues. Thanks to everybody who taught me new techniques, supported me with sample as well as data analysis and who took care for animal husbandry: Andrea Meinhardt, Marco Niesche (both CRTD, Dresden, Tanaka group) and Agnieszka Stec (CRTD, Dresden, Ader group), for support
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