PROJECT 6

Mechanisms of Retinal ganglion cells/glial cells uncoupling by glaucoma associated stress and their association with neuronal cell death

Why?
Glaucoma is characterized by retinal ischemia, central BRB alteration and inflammation leading to retinal ganglion cell (RGC) loss. Hyperlipidemia is associated with elevated ocular intraocular pressure (IOP) leading to glaucoma. Glaucoma-associated neuronal-glia uncoupling leads to cell death, including neuronal cell apoptosis and lipid-dependent ferroptosis. Our preliminary results indicate that exposure of retinal glial cells to plasma lipids reduces their tolerance to oxidated lipids. We hypothesize that modification of glial function secondary to lipid exposure, ischemia and/or hypoglycemia modulates glial-neuronal coupling and promotes RGC ferroptosis-dependent cell death.

How?
iPSCs lines with modifications in ferroptotic-related genes, such as Gpx4, ferritin or NCOA4 and their corresponding isogenic lines will be generated using CRISPR genome engineering. Next, we will generate brain and retinal organoids and retinal Muller Glial cells (RMG). In parallel, we will differentiate the iPSC lines into microglial cells and will integrate them into the brain organoids. Mixed co-cultures of either controls or ferroptosis-related RMGs and neurons will be generated and the survival of neurons or RGC in the mixed co-cultures will be evaluated in the presence of glaucoma-associated stress (hypoxia, dyslipidemia and glucose deprivation). Protective molecules will be tested under the same conditions for their ability to normalize neuronal/glial interactions.

What can you expect?
The candidate will benefit from internationally-recognized expertise in the field of induced pluripotent stem cell-derived neuronal and glial cell culture1-5. The host laboratories have strong expertise in retinal inflammation, cell death mechanisms and deep retinal phenotyping (FACS, transcriptomic and single cell transcriptomic)2. The candidate will be trained to use these techniques and will have access to all required resources and state-of-the-art facilities and infrastructure.

Where?
The research project is a joint-doctorate between the Institut de la Vision (FR) and European Research Institute Biology of Aging (ERIBA, NL). The Vision Institute (Sorbonne-Université) is one of the largest European center for integrated vision research. Located in Paris at the heart of the National Ophthalmology Hospital, it brings together fundamental, clinical and industrial research at the same site in order to accelerate the transition between basic and applied research. Institut de la vision combines all the sate of art technological and eye specialized (surgery, imaging, vision evaluation) facilities. Here, the candidate part of Xavier Guillonneau’s lab, that focuses on the involvement of inflammatory mechanisms in retinal vascular diseases (diabetic retinopathy and retinopathy of prematurity) and in neurodegenerative processes associated with age related macular degeneration. At ERIBA, part of the University Medical Center Groningen, the Functional Genomics Center is a research facility that provides scientists with expertise, training and research support for iPSC and CRISPR-related experiments. In addition, ERIBA provide scientists access to a culture robot to expedite the generation of (patient-derived) iPSCs in a high throughput manner. At ERIBA, the candidate will join the laboratory of Genomic Instability in Development and Disease led by Prof. Floris Foijer, that focuses on the in vivo consequences of chromosomal instability.

Who are we looking for?
Highly-motivated candidates with ample experience with cell culture (ideally stem cell culture) and a strong interest in mechanisms of cell death and inflammation. The candidate is expected to be self-motivated, curious, proactive and have strong communicational skills. As the student will be appointed on a double degree program, part of the project will be performed in France and another part in the Netherlands.

References

  • Couturier, A., Blot, G., Vignaud, L., Nanteau, C., Slembrouck-Brec, A., Fradot, V., Acar, N., Sahel, J.A., Tadayoni, R., Thuret, G., Sennlaub, F., Roger, J.E., Goureau, O., Guillonneau*, X., and Reichman*, S.,Reproducing diabetic retinopathy features using newly developed human induced-pluripotent stem cell-derived retinal Muller glial cells, Glia (2021). 10.1002/glia.23983.
  • Majerníková N, den Dunnen WFA, Dolga AM. The Potential of Ferroptosis-Targeting Therapies for Alzheimer’s Disease: From Mechanism to Transcriptomic Analysis. Front Aging Neurosci. 2021 Dec 20;13:745046.
  • Sabogal-Guáqueta AM, Marmolejo-Garza A, de Pádua VP, Eggen B, Boddeke E, Dolga AM. Microglia alterations in neurodegenerative diseases and their modeling with human induced pluripotent stem cell and other platforms. Prog Neurobiol. 2020 Jul;190:101805.
  • Neitemeier S, Jelinek A, Laino V, Hoffmann L, Eisenbach I, Eying R, Ganjam GK, Dolga AM, Oppermann S, Culmsee C. BID links ferroptosis to mitochondrial cell death pathways. Redox Biol. 2017 Aug;12:558-570.
  • Guillonneau, X., Eandi, C.M., Paques, M., Sahel, J.A., Sapieha, P., and Sennlaub, F.,On phagocytes and macular degeneration, Progress in Retinal and Eye Research (2017). 10.1016/j.preteyeres.2017.06.002.