Building a glaucoma model
Dr Yann Bouremel | GR001091
24 February 2021
Researchers at the UCL Institute of Ophthalmology are developing a 3D model to investigate the mechanisms underlying glaucoma.
Glaucoma is the leading cause of irreversible blindness in the world. It is most commonly caused by raised pressure in the eye that over time will cause damage to the optic nerve. This nerve is critical for vision.
What is glaucoma?
Glaucoma is when damage to the optic nerve causes sight loss. It is usually caused by high pressure inside your eye.
The eye is full of fluid, which helps it to keep its shape and function properly. However, if too much fluid builds up inside the eye, the pressure rises and squeezes the optic nerve at the back of the eye. This can cause damage to your optic nerve - a bundle of over a million nerve fibres that carry signals between your eye and your brain.
Pressure can build up in the eye when:
- fluid has difficulty training away;
- extra fluid is produces after an eye injury or infection - this is called secondary glaucoma;
- there is an abnormality in the shape of the eye in children - this is called congenital glaucoma.
Glaucoma tends to develop slowly over many years. As there is currently no cure for glaucoma, treatment focuses on early diagnosis, careful monitoring and regular treatment to help prevent further sight loss.
If left untreated, glaucoma can lead to blindness. It is not currently possible to repair the optic nerve once it has been damaged, so any vision lost to glaucoma cannot be recovered. There are usually no symptoms of a rising pressure in the eye until sight loss occurs, so regular eye tests are the best way to help spot the condition early.
Despite extensive ongoing research efforts across the world, the process by which high intraocular pressure causes sight loss are still unclear.
One particular area of research focusses how exactly nerve fibres get damaged by high pressure. Nerve fibres are normally protected by specialised support cells, called Müller cells. It’s not known how this protection is lost in glaucoma to result in damage to the optic nerve.
Finding a solution
This Springboard Award granted to Dr Yann Bouremel will investigate the effects of high eye pressure on Müller glial cells using an in vitro laboratory model.
The model will be made by attaching the Müller cells to a curved silicone retinal model. This is then embedded in a specialised 3D-printed chamber. Later, this model will be amended to also incorporate retinal ganglion cells.
A strength of this model is that the synthetic retina will be flexible. This allows Yann and the team – Dr Karen Eastlake, Ms Heesoon Park, Dr Christin Henein, Professor Astrid Limb and Professor Peng Khaw – to test a system that is one step closer to what really happens in the eye.
They will be able to precisely control the delivery of nutrients, removal of waste products and, crucially, the pressure exerted on the cells within the chamber. The impact on cells and their survival rate can then be monitored.
Thanks to Moorfields Eye Charity, we are developing a cutting-edge experimental mechanotransduction model of the optic nerve at the interface of engineering and biology.
Dr Yann Bouremel, UCL Institute of Ophthalmology
This innovative model bridges the interface between cell biology and microfluidic engineering.
The team hope this dynamic model will help uncover mechanisms that trigger cell death in glaucoma. This would enhance understanding of early events in glaucoma initiation. This should then offer opportunities for earlier diagnosis and might flag up new therapeutic targets.
Moreover, this project offers a valuable opportunity to develop a dynamic laboratory model for retinal disease as an alternative to animal models. The optic-nerve-on-a-chip model developed here may therefore be used a platform for future pre-clinical studies.
Dr Yann Bouremel