Characterisation and treatment of patient iPSC-derived retinal organoids as an in vitro model of inherited retinal disease
LEAD SUPERVISOR: Professor Robert E MacLaren, Nuffield Department of Clinical Neurosciences
Co-supervisor: Dr Michelle McClements, Nuffield Department of Clinical Neurosciences
Commercial partner: Newcells Biotech Ltd, Newcastle upon Tyne
Induced pluripotent stem cell (iPSC) derived 3D retinal organoids (ROs) mimic the architecture of the mammalian retina and can therefore be used as a physiologically relevant in vitro model. ROs represent the future of pre-clinical testing for advanced therapeutics and the next generation of gene therapies. Developing patient derived ROs allows the assessment of both the impact of disease-causing mutations and the testing of new therapies. In addition, by assessing treatment efficacy in patient-derived ROs, the need for the development of mutation-specific transgenic animals will be reduced whilst also generating valuable data that will provide strong support for future clinical trials.
The development of ROs is highly specialised and time consuming but Newcells Biotech have optimised the pipeline (1,2). As a producer of ROs derived from healthy donors they are active collaborators with academics in developing models to further understand and treat retinal disease (3). This collaborative project is designed to combine the expertise of gene therapy development for retinal disease of the MacLaren research team and the specialised RO development at Newcells Biotech to:
- Advance understanding of the impact of genetic mutations on retinal structure and function.
- Advance to clinical trial the next generation of gene therapy vectors.
If awarded, this studentship will include learning the RO development process at Newcells Biotech, generating ROs from patient samples, characterising them for genetic and morphological differences compared to ROs from control samples. At the University of Oxford, gene therapy vectors will be developed and applied to the generated ROs and subsequent assessments of vector efficacy will be made.
We are particularly interested in investigating mutations in the rhodopsin gene, which are responsible for 30-40% of autosomal dominant cases of retinitis pigmentosa with >100 distinct mutations identified to date. We intend to enrol patients attending routine clinic appointments from whom we can extract blood samples for PBMC isolation, which will be sent to Newcells Biotech for iPSC and RO generation. Developing and characterising ROs from patients carrying different rhodopsin mutations will provide valuable insights into the disease and how it differs (or indeed is similar) depending on the mutation. It would then be of great interest to compare different treatment strategies on the generated ROs. For example, the MacLaren research team has developed a knockdown-replacement strategy for rhodopsin-related disease (4) that we hope to test in Phase 1 human trials within the next three years. Assessing the treatment effect across ROs representing a spectrum of mutation types could fast-track the regulatory approval process. Preliminary work already conducted with Newcells Biotech has enabled us to optimise AAV vector delivery to ROs (5). Additionally, the ROs will also be highly valuable in the assessment of mutation-specific strategies with CRISPR-based vectors that our research team is also developing.
- Chichagova V, Dorgau B, Felemban M, Georgiou M, Armstrong L, Lako M. Differentiation of Retinal Organoids from Human Pluripotent Stem Cells. Curr Protoc Stem Cell Biol. 2019;50(1):e95. https://doi.org/10.1002/cpsc.95.
- Chichagova V, Hilgen G, Ghareeb A, Georgiou M, Carter M, Sernagor E, Lako M, Armstrong L. Human iPSC differentiation to retinal organoids in response to IGF1 and BMP4 activation is line- and method-dependent. Stem Cells. 2020;38(2):195-201. https://doi.org/10.1002/stem.3116.
- Buskin A, Zhu L, Chichagova V, Basu B, Mozaffari-Jovin S, Dolan D, Droop A, Collin J, Bronstein R, Mehrotra S, Farkas M, Hilgen G, White K, Pan KT, Treumann A, Hallam D, Bialas K, Chung G, Mellough C, Ding Y, Krasnogor N, Przyborski S, Zwolinski S, Al-Aama J, Alharthi S, Xu Y, Wheway G, Szymanska K, McKibbin M, Inglehearn CF, Elliott DJ, Lindsay S, Ali RR, Steel DH, Armstrong L, Sernagor E, Urlaub H, Pierce E, Lührmann R, Grellscheid SN, Johnson CA, Lako M. Disrupted alternative splicing for genes implicated in splicing and ciliogenesis causes PRPF31 retinitis pigmentosa. Nat Commun. 2018;9(1):4234. https://doi.org/10.1038/s41467-018-06448-y.
- Orlans HO, McClements ME, Barnard AR, Martinez-Fernandez de la Camara C, MacLaren RE. Mirtron-mediated RNA knockdown/replacement therapy for the treatment of dominant retinitis pigmentosa. Nat Commun. 2021;12(1):4934. https://doi.org/10.1038/s41467-021-25204-3.
- McClements ME, Steward H, Atkin W, Goode EA, Gándara C, Chichagova V, MacLaren RE. Tropism of AAV Vectors in Photoreceptor-Like Cells of Human iPSC-Derived Retinal Organoids. Transl Vis Sci Technol. 2022;11(4):3. https://doi.org/10.1167/tvst.11.4.3.
Apply using course: DPhil in Clinical Neurosciences