3D mini-brains made from human cells could help researchers study myelin damage and screen potential treatments for multiple sclerosis (MS).
The models are about the size of a grain of rice and allow researchers to observe myelin destruction, known as demyelination, and its repair, or remyelination, in human cells.
Myelin is the fatty sheath that protects nerve fibres and helps electrical signals travel through the brain, spinal cord and body.+
The models were developed over more than six years by researchers led by The Florey Institute of Neuroscience and Mental Health and Monash University, alongside collaborators in Australia and New Zealand.
Associate professor Samantha Barton, who leads the Myelin in Health and Disease Group at The Florey, said drugs that work in rodent disease models are rarely effective in people, making more human-relevant systems important.
She said: “The relevance of our new system is significant. In addition to generating myelin, we have been able to introduce immune cells to trigger injury similar to MS.
“This gives us the unique opportunity to study the regenerative process of remyelination in the laboratory.”
Scientists used reprogrammed adult stem cells to create the models and introduced immune cells to produce injury resembling the myelin damage seen in multiple sclerosis.
MS is an autoimmune condition in which the immune system mistakenly attacks myelin, causing nerve damage, neurological symptoms and, over time, disability.
The researchers said the models could provide a more human-relevant way to investigate how myelin is damaged and repaired and to screen drugs that could protect or restore it.
There are currently no therapies that repair myelin damage caused by MS, while existing medications can treat symptoms and slow progression.
Barton said the model could help researchers understand what drives myelin damage and repair while providing a platform for screening drugs that protect or restore myelin.
The project also involved researchers from the University of Melbourne, University of Auckland, WEHI and University of Canberra.
First author Dr Shwathy Ramesan, a postdoctoral fellow at The Florey, said the system could allow researchers to observe potential treatments working on human cells.
She said: “After years of developing and refining this model, it’s exciting to see it provide a window into human myelin biology that wasn’t previously available.
“We hope it becomes a valuable tool not only for our team but for researchers studying MS around the world.”
Co-senior author associate professor David Gonsalvez, from Monash University, said the technology could also be used to explore potential treatments that may improve the body’s own repair processes.
