A retina-on-a-chip, which blends living human cells with an artificial tissue-like system, has been developed by scientists in Germany. The cutting-edge tool may provide a useful alternative to existing models for studying eye disease and allow scientists to test the effects of drugs on the retina more efficiently.
Many diseases that cause blindness – such as Stargardt disease, age-related macular degeneration or retinitis pigmentosa – harm the retina, a thin layer of tissue at the back of the eye that helps collect light and relay visual information to the brain. The retina is also vulnerable to harmful side effects of drugs used to treat other diseases such as cancer.
Currently, scientists often rely on animals or retina organoids, tiny retina-like structures grown from human stem cells, to study eye diseases and drug side effects. But results from studies in both models often fail to describe disease and drug effects in people accurately.
3D Retinal Model
To overcome these challenges, the team of scientists coaxed human pluripotent stem cells to develop into several different types of retina cells on artificial tissue. This tissue recreates the environment that cells would experience in the body and delivers nutrients and drugs to the cells through a system that mimics human blood vessels.
“This combination of approaches enabled us to successfully create a complex multi-layer structure that includes all cell types and layers present in retinal organoids, connected to a retinal pigment epithelium layer. It is the first demonstration of a 3D retinal model that recreates many of the structural characteristics of the human retina and behaves in a similar way,”
says co-lead author Kevin Achberger, Postdoctoral Researcher at the Department of Neuroanatomy & Developmental Biology at the Eberhard Karls University of Tuebingen.
The team treated their retina-on-the-chip with the anti-malaria drug chloroquine and the antibiotic gentamicin, which are toxic to the retina. They found that the drugs had a toxic effect on the retinal cells in the model, suggesting that it could be a useful tool for testing for harmful drug effects.