| 研究生: |
朱昱如 Yu-Ru Zhu |
|---|---|
| 論文名稱: |
人類多能幹細胞分化視網膜色素上皮細胞培養於各種塗佈細胞外間質 Differentiation of Human Pluripotent Stem Cells into Retinal Pigmented Epithelium on ECM-coated Surfaces |
| 指導教授: |
樋口亞紺
Akon Higuchi |
| 口試委員: | |
| 學位類別: |
碩士 Master |
| 系所名稱: |
工學院 - 化學工程與材料工程學系 Department of Chemical & Materials Engineering |
| 論文出版年: | 2021 |
| 畢業學年度: | 109 |
| 語文別: | 英文 |
| 論文頁數: | 102 |
| 中文關鍵詞: | 細胞外基質 、生醫材料 、人類多能幹細胞 、細胞分化 、視網膜色素上皮細胞 |
| 外文關鍵詞: | ECM, biomaterials, human pluripotent stem cells, cell differentiation, retinal pigment epithelium |
| 相關次數: | 點閱:11 下載:0 |
| 分享至: |
| 查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報 |
人類多能幹細胞包括人類胚胎幹細胞和人類誘導多能幹細胞,而人類多能幹細胞可成為用於特定疾病的潛在療法。來自世界衛生組織的資料顯示老年性黃斑部病變是視力損害的第三大原因,且預計未來會變得越來越嚴重。80-90% 的老年性黃斑部病變主要由視網膜色素上皮的功能損壞而引起。幸運的是,移植人類多能幹細胞分化成的視網膜色素上皮細胞可以作為治癒老年性黃斑部病變疾病的方法。然而,來自人類多能幹細胞的視網膜色素上皮通常存在著純度不足和培養時間長的問題。因此,在本篇研究中有比較不同的培養製程和嘗試各種細胞外基質來評估哪些條件最適合人類多能幹細胞分化為視網膜色素上皮細胞。我測試了人類多能幹細胞分化為視網膜色素上皮細胞三種類型的培養製程(N2、NIC84 和Activin A 培養製程)。每個培養製程都經過進一步修改來提高人類多能幹細胞分化為成熟視網膜色素上皮的效率。在本研究中,我以原來的NIC84培養製成進行以下調整,(1) 降低 CTM 濃度;(2) 改變細胞繼代方式;(3) 減少製成前28天的培養液使用量。經過這些調整,可以用此改良後的培養製成高效地獲得從人類誘導多能幹細胞分化成的成熟視網膜色素上皮細胞。在此研究中,也有對這些細胞進行相關的驗證程序及檢測。視網膜色素上皮細胞因為有色素沉澱之功能,呈色為棕色,而我從人類誘導多能幹細胞誘導成的視網膜色素上皮細胞也呈棕色。加上這些視網膜色素上皮細胞有表達ZO-1和 RPE65 的這兩個代表成熟視網膜色素上皮細胞的標記。透過細胞顏色的轉變及特定抗體的標記,可證明改良後的NIC84培養製程可使人類多能幹細胞分化成視網膜色素上皮細胞。接著在不同的細胞外基質上,透過特定抗體的標記比例及細胞生長速率我發現擁有Matrigel 塗層和 LN-521 塗層之培養皿較擁有rVN 塗層、LN-511 塗層和 Synthemax II 塗層之培養皿更能支持人類多能幹細胞分化成視網膜色素上皮細胞。
Human pluripotent stem cells (hPSCs) include human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs), where hPSCs can be used for the potential cell therapy toward specific disease. Age-related macular degeneration (AMD), which ranks the third leading cause of vision impairment according to world health organization (WHO), is expected to become more and more serious in the future. 80-90% of AMD disease mainly results from the dysfunction of the retinal pigmented epithelium (RPE). Fortunately, transplantation of hPSCs-derived RPE can serve as a regenerative approach to cure AMD disease. However, RPE derived from hPSCs usually suffers from insufficient purity and long culture period. Therefore, different protocols and cell culture extracellular matrices (ECMs) were investigated to evaluate which conditions would be the most suitable for hPSCs to differentiate into RPE in this study. Three types of protocols (N2, NIC84, and Activin A protocols) for hiPSC differentiation into RPE were evaluated. Each protocol was further modified to improve the efficiency of differentiation into mature RPE. Mature RPE differentiated from hiPSCs can be obtained with high efficiency using the modified protocol of NIC84 with reducing concentration of CTM and modified medium in day 28-30 of differentiation, which was developed in this study. hiPSC-derived RPE showed brown color indicating pigmented cells (mature RPE) and expressed mature RPE marker of ZO-1 and RPE65. Matrigel-coated and LN-521-coated dishes supported high differentiation of hiPSCs into RPE compared to rVN-coated, LN-511-coated, and Synthemax II-coated dishes.
1. O. Forostyak, G.D., S. Forostyak, CNS Regenerative Medicine and Stem Cells. Opera Med Physiol, 2016. 2: p. 55-62.
2. Mitalipov, S. and D. Wolf, Totipotency, pluripotency and nuclear reprogramming. Adv Biochem Eng Biotechnol, 2009. 114: p. 185-99.
3. Higuchi, A., et al., Polymeric design of cell culture materials that guide the differentiation of human pluripotent stem cells. Progress in Polymer Science, 2017. 65: p. 83-126.
4. Kimbrel, E.A. and R. Lanza, Current status of pluripotent stem cells: moving the first therapies to the clinic. Nat Rev Drug Discov, 2015. 14(10): p. 681-92.
5. Hoffman, L.M. and M.K. Carpenter, Characterization and culture of human embryonic stem cells. Nat Biotechnol, 2005. 23(6): p. 699-708.
6. Vazin, T. and W.J. Freed, Human embryonic stem cells: derivation, culture, and differentiation: a review. Restor Neurol Neurosci, 2010. 28(4): p. 589-603.
7. Amit, M., et al., Clonally derived human embryonic stem cell lines maintain pluripotency and proliferative potential for prolonged periods of culture. Dev Biol, 2000. 227(2): p. 271-8.
8. MJEMH, K., Establishment in culture of pluripotential cells from mouse embryos. Nature, 1981. 292: p. 154-6.
9. J.A. Thomson, e.a., Embryonic Stem Cell Lines Derived from Human Blastocysts. SCIENCE, 1998. 282(1): p. 1145-1147.
10. JHPH, E.H.L., The potential of stem cells in orthopaedic surgery. JOURNAL OF BONE AND JOINT SURGERY-BRITISH VOLUME, 2006. 88B: p. 841-51.
11. Trounson, A. and N.D. DeWitt, Pluripotent stem cells progressing to the clinic. Nat Rev Mol Cell Biol, 2016. 17(3): p. 194-200.
12. Lo, B. and L. Parham, Ethical issues in stem cell research. Endocr Rev, 2009. 30(3): p. 204-13.
13. Abou-Saleh, H., et al., The march of pluripotent stem cells in cardiovascular regenerative medicine. Stem Cell Res Ther, 2018. 9(1): p. 201.
14. Okita, K., et al., A more efficient method to generate integration-free human iPS cells. Nature methods, 2011. 8(5): p. 409.
15. Fusaki, N., et al., Efficient induction of transgene-free human pluripotent stem cells using a vector based on Sendai virus, an RNA virus that does not integrate into the host genome. Proc Jpn Acad Ser B Phys Biol Sci, 2009. 85(8): p. 348-62.
16. Stadtfeld, M., et al., Induced pluripotent stem cells generated without viral integration. 2008. 322(5903): p. 945-949.
17. Warren, L., et al., Highly efficient reprogramming to pluripotency and directed differentiation of human cells with synthetic modified mRNA. Cell Stem Cell, 2010. 7(5): p. 618-30.
18. Kim, D., et al., Generation of human induced pluripotent stem cells by direct delivery of reprogramming proteins. Cell Stem Cell, 2009. 4(6): p. 472-6.
19. Takahashi, K., et al., Induction of pluripotent stem cells from adult human fibroblasts by defined factors. Cell, 2007. 131(5): p. 861-72.
20. Takahashi, K. and S. Yamanaka, Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors. Cell, 2006. 126(4): p. 663-76.
21. Nori, S., et al., Grafted human-induced pluripotent stem-cell-derived neurospheres promote motor functional recovery after spinal cord injury in mice. Proc Natl Acad Sci U S A, 2011. 108(40): p. 16825-30.
22. Yamanaka, S., A fresh look at iPS cells. Cell, 2009. 137(1): p. 13-7.
23. Bahmad, H., et al., Modeling Human Neurological and Neurodegenerative Diseases: From Induced Pluripotent Stem Cells to Neuronal Differentiation and Its Applications in Neurotrauma. Front Mol Neurosci, 2017. 10: p. 50.
24. Hyun, I., The bioethics of stem cell research and therapy. J Clin Invest, 2010. 120(1): p. 71-5.
25. Power, C.a.J.E.R., Will cell reprogramming resolve the embryonic stem cell controversy? A narrative review. Annals of internal medicine, 2011. 155(2): p. 114-121.
26. Gonzalez, F., S. Boue, and J.C. Izpisua Belmonte, Methods for making induced pluripotent stem cells: reprogramming a la carte. Nat Rev Genet, 2011. 12(4): p. 231-42.
27. Yamanaka, S., Induced pluripotent stem cells: past, present, and future. Cell Stem Cell, 2012. 10(6): p. 678-684.
28. Gore, A., et al., Somatic coding mutations in human induced pluripotent stem cells. Nature, 2011. 471(7336): p. 63-7.
29. Hussein, S.M., et al., Copy number variation and selection during reprogramming to pluripotency. Nature, 2011. 471(7336): p. 58-62.
30. Zhao, T., et al., Immunogenicity of induced pluripotent stem cells. Nature, 2011. 474(7350): p. 212-5.
31. Rao, M.S. and N. Malik, Assessing iPSC reprogramming methods for their suitability in translational medicine. J Cell Biochem, 2012. 113(10): p. 3061-8.
32. Rathod, R., et al., Induced pluripotent stem cells (iPSC)-derived retinal cells in disease modeling and regenerative medicine. J Chem Neuroanat, 2019. 95: p. 81-88.
33. Mao, A.S. and D.J. Mooney, Regenerative medicine: Current therapies and future directions. Proc Natl Acad Sci U S A, 2015. 112(47): p. 14452-9.
34. Mahla, R.S., Stem Cells Applications in Regenerative Medicine and Disease Therapeutics. Int J Cell Biol, 2016. 2016: p. 6940283.
35. Tongers, J., D.W. Losordo, and U. Landmesser, Stem and progenitor cell-based therapy in ischaemic heart disease: promise, uncertainties, and challenges. Eur Heart J, 2011. 32(10): p. 1197-206.
36. Shadrin, I.Y., et al., Cardiopatch platform enables maturation and scale-up of human pluripotent stem cell-derived engineered heart tissues. Nat Commun, 2017. 8(1): p. 1825.
37. Higuchi, A., et al., Stem cell therapies for myocardial infarction in clinical trials: bioengineering and biomaterial aspects. Lab Invest, 2017. 97(10): p. 1167-1179.
38. Singh, R.K. and I.O. Nasonkin, Limitations and Promise of Retinal Tissue From Human Pluripotent Stem Cells for Developing Therapies of Blindness. Front Cell Neurosci, 2020. 14: p. 179.
39. Okamoto, S. and M. Takahashi, Induction of retinal pigment epithelial cells from monkey iPS cells. Invest Ophthalmol Vis Sci, 2011. 52(12): p. 8785-90.
40. Davis, R.J., et al., The Developmental Stage of Adult Human Stem Cell-Derived Retinal Pigment Epithelium Cells Influences Transplant Efficacy for Vision Rescue. Stem Cell Reports, 2017. 9(1): p. 42-49.
41. Kamao, H., et al., Characterization of human induced pluripotent stem cell-derived retinal pigment epithelium cell sheets aiming for clinical application. Stem Cell Reports, 2014. 2(2): p. 205-18.
42. Ratcliffe, E., et al., Current status and perspectives on stem cell-based therapies undergoing clinical trials for regenerative medicine: case studies. Br Med Bull, 2013. 108: p. 73-94.
43. Trounson, A. and C. McDonald, Stem Cell Therapies in Clinical Trials: Progress and Challenges. Cell Stem Cell, 2015. 17(1): p. 11-22.
44. Rong, Z., et al., A scalable approach to prevent teratoma formation of human embryonic stem cells. J Biol Chem, 2012. 287(39): p. 32338-45.
45. aklenec, A., et al., Progress in the tissue engineering and stem cell industry “are we there yet? Tissue Engineering Part B: Reviews, 2012. 18(3): p. 155-166.
46. Abbasalizadeh, S. and H. Baharvand, Technological progress and challenges towards cGMP manufacturing of human pluripotent stem cells based therapeutic products for allogeneic and autologous cell therapies. Biotechnol Adv, 2013. 31(8): p. 1600-23.
47. Villa-Diaz, L.G., et al., Concise review: The evolution of human pluripotent stem cell culture: from feeder cells to synthetic coatings. Stem Cells, 2013. 31(1): p. 1-7.
48. Higuchi, A., et al., Design of polymeric materials for culturing human pluripotent stem cells: Progress toward feeder-free and xeno-free culturing. Progress in Polymer Science, 2014. 39(7): p. 1348-1374.
49. Mallon, B.S., et al., Toward xeno-free culture of human embryonic stem cells. Int J Biochem Cell Biol, 2006. 38(7): p. 1063-75.
50. International Stem Cell Initiative, C., et al., Comparison of defined culture systems for feeder cell free propagation of human embryonic stem cells. In Vitro Cell Dev Biol Anim, 2010. 46(3-4): p. 247-58.
51. Hughes, C.S., L.M. Postovit, and G.A. Lajoie, Matrigel: a complex protein mixture required for optimal growth of cell culture. Proteomics, 2010. 10(9): p. 1886-90.
52. Kleinman, H.K. and G.R. Martin, Matrigel: basement membrane matrix with biological activity. Semin Cancer Biol, 2005. 15(5): p. 378-86.
53. Chen, Kevin G., et al., Human Pluripotent Stem Cell Culture: Considerations for Maintenance, Expansion, and Therapeutics. Cell Stem Cell, 2014. 14(1): p. 13-26.
54. Higuchi, A., et al., Biomaterials for the feeder-free culture of human embryonic stem cells and induced pluripotent stem cells. Chem Rev, 2011. 111(5): p. 3021-35.
55. Abedin, M. and N. King, Diverse evolutionary paths to cell adhesion. Trends Cell Biol, 2010. 20(12): p. 734-42.
56. Bonnans, C., J. Chou, and Z. Werb, Remodelling the extracellular matrix in development and disease. Nat Rev Mol Cell Biol, 2014. 15(12): p. 786-801.
57. Kechagia, J.Z., J. Ivaska, and P. Roca-Cusachs, Integrins as biomechanical sensors of the microenvironment. Nat Rev Mol Cell Biol, 2019. 20(8): p. 457-473.
58. Higuchi, A., et al., Biomimetic cell culture proteins as extracellular matrices for stem cell differentiation. Chem Rev, 2012. 112(8): p. 4507-40.
59. Rodin, S., et al., Long-term self-renewal of human pluripotent stem cells on human recombinant laminin-511. Nat Biotechnol, 2010. 28(6): p. 611-5.
60. Rowland, T.J., et al., Roles of integrins in human induced pluripotent stem cell growth on Matrigel and vitronectin. Stem Cells Dev, 2010. 19(8): p. 1231-40.
61. Melkoumian, Z., et al., Synthetic peptide-acrylate surfaces for long-term self-renewal and cardiomyocyte differentiation of human embryonic stem cells. Nat Biotechnol, 2010. 28(6): p. 606-10.
62. Villa-Diaz, L.G., et al., Synthetic polymer coatings for long-term growth of human embryonic stem cells. Nat Biotechnol, 2010. 28(6): p. 581-3.
63. Brafman, D.A., et al., Long-term human pluripotent stem cell self-renewal on synthetic polymer surfaces. Biomaterials, 2010. 31(34): p. 9135-44.
64. Kharitonov, A.E., Surdina, A.V., Lebedeva, O.S., Bogomazova, A.N., and Lagarkova, M.A., Possibilities for Using Pluripotent Stem Cells for Restoring Damaged Eye Retinal Pigment Epithelium. Acta Nat., 2018. 10(3): p. 30-39.
65. Wong, W.L., et al., Global prevalence of age-related macular degeneration and disease burden projection for 2020 and 2040: a systematic review and meta-analysis. The Lancet Global Health, 2014. 2(2): p. e106-e116.
66. Flaxman, S.R., et al., Global causes of blindness and distance vision impairment 1990–2020: a systematic review and meta-analysis. The Lancet Global Health, 2017. 5(12): p. e1221-e1234.
67. Mitchell, P., et al., Age-related macular degeneration. The Lancet, 2018. 392(10153): p. 1147-1159.
68. Al-Khersan, H., et al., Innovative therapies for neovascular age-related macular degeneration. Expert Opin Pharmacother, 2019. 20(15): p. 1879-1891.
69. Plaza Reyes, A., et al., Xeno-Free and Defined Human Embryonic Stem Cell-Derived Retinal Pigment Epithelial Cells Functionally Integrate in a Large-Eyed Preclinical Model. Stem Cell Reports, 2016. 6(1): p. 9-17.
70. MacLaren, R.E., J. Bennett, and S.D. Schwartz, Gene Therapy and Stem Cell Transplantation in Retinal Disease: The New Frontier. Ophthalmology, 2016. 123(10S): p. S98-S106.
71. Nazari, H., et al., Stem cell based therapies for age-related macular degeneration: The promises and the challenges. Prog Retin Eye Res, 2015. 48: p. 1-39.
72. Morizur, L., et al., Human pluripotent stem cells: A toolbox to understand and treat retinal degeneration. Mol Cell Neurosci, 2020. 107: p. 103523.
73. Leach, L.L. and D.O. Clegg, Concise Review: Making Stem Cells Retinal: Methods for Deriving Retinal Pigment Epithelium and Implications for Patients With Ocular Disease. Stem Cells, 2015. 33(8): p. 2363-73.
74. Zhao, C., Q. Wang, and S. Temple, Stem cell therapies for retinal diseases: recapitulating development to replace degenerated cells. Development, 2017. 144(8): p. 1368-1381.
75. Reichman, S., et al., Generation of Storable Retinal Organoids and Retinal Pigmented Epithelium from Adherent Human iPS Cells in Xeno-Free and Feeder-Free Conditions. Stem Cells, 2017. 35(5): p. 1176-1188.
76. Reichman, S., et al., From confluent human iPS cells to self-forming neural retina and retinal pigmented epithelium. Proc Natl Acad Sci U S A, 2014. 111(23): p. 8518-23.
77. Ben M'Barek, K., et al., Human ESC-derived retinal epithelial cell sheets potentiate rescue of photoreceptor cell loss in rats with retinal degeneration. Science Translational Medicine, 2017. 9(421): p. 12.
78. Slembrouck-Brec, A., et al., Defined Xeno-free and Feeder-free Culture Conditions for the Generation of Human iPSC-derived Retinal Cell Models. J Vis Exp, 2018(139).
79. Maruotti, J., et al., A simple and scalable process for the differentiation of retinal pigment epithelium from human pluripotent stem cells. Stem Cells Transl Med, 2013. 2(5): p. 341-54.
80. Klimanskaya I, H.J., Rezai KA, West M, Atala A and Lanza R, Derivation and comparative assessment of retinal pigment epithelium from human embryonic stem cells using transcriptomics. Cloning Stem Cells, 2004. 6: p. 217-45
81. Buchholz, D.E., et al., Derivation of functional retinal pigmented epithelium from induced pluripotent stem cells. Stem Cells, 2009. 27(10): p. 2427-34.
82. Cho, M.S., et al., Generation of retinal pigment epithelial cells from human embryonic stem cell-derived spherical neural masses. Stem Cell Res, 2012. 9(2): p. 101-9.
83. Ferguson LR, B.S., Mynampati BK, Sambhav K and Chalam KV, Deprivation of bFGF Promotes Spontaneous Differentiation of Human Embryonic Stem Cells into Retinal Pigment Epithelial Cells. J Stem Cells, 2015. 10: p. 159-70.
84. Reichman, S. and O. Goureau, Production of Retinal Cells from Confluent Human iPS Cells. Methods Mol Biol, 2016. 1357: p. 339-51.
85. Hirami, Y., et al., Generation of retinal cells from mouse and human induced pluripotent stem cells. Neurosci Lett, 2009. 458(3): p. 126-31.
86. Osakada, F., et al., Toward the generation of rod and cone photoreceptors from mouse, monkey and human embryonic stem cells. Nat Biotechnol, 2008. 26(2): p. 215-24.
87. Osakada, F., et al., In vitro differentiation of retinal cells from human pluripotent stem cells by small-molecule induction. J Cell Sci, 2009. 122(Pt 17): p. 3169-79.
88. Idelson, M., et al., Directed differentiation of human embryonic stem cells into functional retinal pigment epithelium cells. Cell Stem Cell, 2009. 5(4): p. 396-408.
89. Maruotti, J., et al., Small-molecule-directed, efficient generation of retinal pigment epithelium from human pluripotent stem cells. Proc Natl Acad Sci U S A, 2015. 112(35): p. 10950-5.
90. Smith, E.N., et al., Human iPSC-Derived Retinal Pigment Epithelium: A Model System for Prioritizing and Functionally Characterizing Causal Variants at AMD Risk Loci. Stem Cell Reports, 2019. 12(6): p. 1342-1353.
91. Zhu, Y., et al., Three-dimensional neuroepithelial culture from human embryonic stem cells and its use for quantitative conversion to retinal pigment epithelium. PLoS One, 2013. 8(1): p. e54552.
92. Michelet, F., et al., Rapid generation of purified human RPE from pluripotent stem cells using 2D cultures and lipoprotein uptake-based sorting. Stem Cell Res Ther, 2020. 11(1): p. 47.
93. Kokkinaki, M., N. Sahibzada, and N. Golestaneh, 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. Stem Cells, 2011. 29(5): p. 825-35.
94. Westenskow, P., et al., Efficient derivation of retinal pigment epithelium cells from stem cells. J Vis Exp, 2015(97).
95. Osakada, F., et al., Stepwise differentiation of pluripotent stem cells into retinal cells. Nat Protoc, 2009. 4(6): p. 811-24.
96. Hongisto, H., et al., Xeno- and feeder-free differentiation of human pluripotent stem cells to two distinct ocular epithelial cell types using simple modifications of one method. Stem Cell Res Ther, 2017. 8(1): p. 291.
97. Choudhary, P., et al., Directing Differentiation of Pluripotent Stem Cells Toward Retinal Pigment Epithelium Lineage. Stem Cells Transl Med, 2017. 6(2): p. 490-501.
98. Ye, K., et al., Reproducible production and image-based quality evaluation of retinal pigment epithelium sheets from human induced pluripotent stem cells. Sci Rep, 2020. 10(1): p. 14387.
99. Buchholz, D.E., et al., Rapid and efficient directed differentiation of human pluripotent stem cells into retinal pigmented epithelium. Stem Cells Transl Med, 2013. 2(5): p. 384-93.
100. Foltz, L.P. and D.O. Clegg, Rapid, Directed Differentiation of Retinal Pigment Epithelial Cells from Human Embryonic or Induced Pluripotent Stem Cells. J Vis Exp, 2017(128).
101. Pennington, B.O., et al., Defined culture of human embryonic stem cells and xeno-free derivation of retinal pigmented epithelial cells on a novel, synthetic substrate. Stem Cells Transl Med, 2015. 4(2): p. 165-77.
102. Matsumoto, E., et al., Fabricating retinal pigment epithelial cell sheets derived from human induced pluripotent stem cells in an automated closed culture system for regenerative medicine. PLoS One, 2019. 14(3): p. e0212369.
103. Depince-Berger, A.E., et al., New tools in cytometry. Morphologie, 2016. 100(331): p. 199-209.
104. Liao, J.L., et al., Molecular signature of primary retinal pigment epithelium and stem-cell-derived RPE cells. Hum Mol Genet, 2010. 19(21): p. 4229-38.
105. Marquardt, T.M., T); Ashery-Padan, R (Ashery-Padan, R); Andrejewski, N (Andrejewski, N); Scardigli, R (Scardigli, R); Guillemot, F (Guillemot, F); Gruss, P (Gruss, P), Pax6 Is Required for the Multipotent state of retinal progenitor cells. CELL, 2001. 105(1): p. 43-55.
106. Vugler, A., et al., Elucidating the phenomenon of HESC-derived RPE: anatomy of cell genesis, expansion and retinal transplantation. Exp Neurol, 2008. 214(2): p. 347-61.