Retina-on-a-chip: the tiny technology offering big hope for inherited sight loss
Researchers in the Netherlands are developing a “retina-on-a-chip” that mimics the key layers of the human retina, offering a powerful new way to study inherited retinal diseases (IRDs) and test potential treatments using human cells.
Researchers at the University of Twente and Radboud University Medical Centre (Radboudumc) in the Netherlands are collaborating to develop an innovative new model of the human retina, which they hope will enhance understanding and accelerate research in the field of IRD treatment.
The retina-on-a-chip model looks to integrate the 3 main-layers of the retina – the choroid, pigment epithelium and nerve layer. The 3 main layers play distinct roles in the retina:
- The choroid is the layer of blood vessels behind the retina that supplies oxygen and nutrients to the outer retina, removes metabolic waste, helps regulate retinal temperature and absorbs excess light.
- The retinal pigment epithelium (RPE) is a layer of cells that support the light-sensing photoreceptor cells. It is essential for the maintenance and protection of photoreceptor cells, responsible for waste clearance, providing metabolic and antioxidant support and the removal of the toxic by-products from the visual cycle.
- The nerve layer includes the photoreceptors and specialised nerve cells which, between them, sense light and convert it into nerve impulses, transmitting visual information to the brain through the optic nerve.
All 3 layers are essential for a healthy retina. A functioning prototype in which the first 2 layers have been successfully integrated (choroid and RPE) has been achieved for the first time, with researchers currently working to develop and integrate the 3rd nerve layer. By combining the cells in layers and mimicking the human retina on a chip, it makes it possible for researchers to follow changes in the retina step-by-step as a result of light, pressure or even medication, as you would see in the human eye.
This is one of many approaches in development that looks to better understand inherited retinal disease and to study possible treatment effects more accurately in human models. This approach, along with research being carried out on retinal organoids which you can read about here, could mean that animal testing would no longer be required in the future.
The retina-on-a-chip model consists of tiny channels that are filled with fluid in which human cells can grow. The partnership between the University of Twente and Radboudumc is the key driver in their developmental success so far, with Radboudumc providing specialised stem cells and expertise on eye disease, and the University providing the essential knowledge on chip technology and bioengineering.
Alongside developing the third layer, researchers are also working on reducing the variation between models and scaling up production. Although this work remains at a very early preclinical stage, initial results and the premise of future applications show great potential for revolutionising the research landscape for inherited retinal diseases.
“Even under optimal conditions, developing new medicines takes five to 10 years, but for rare eye diseases, this technology could provide significant acceleration and new perspectives.” – Andries van der Meer, Researcher, University of Twente