A team of scientists from The Ohio State University have reportedly developed a near-complete human brain from adult skin cells. The brain organoid, which has the maturity of a five-week old fetus, is the most complete brain model developed to date, according to researcher Rene Anand, PhD.
The brain, which is about the size of a pencil eraser, has 99% of the genes present in a human fetal brain and has an identifiable structure. The goal, Anand said, is to use the organioid to study neurological conditions such as autism and Parkinson’s disease that may be less well-served by rodent studies and clinical trials.
“In central nervous system diseases, this will enable studies of either underlying genetic susceptibility or purely environmental influences, or a combination,” Anand said in press release. “Genomic science infers there are up to 600 genes that give rise to autism, but we are stuck there. Mathematical correlations and statistical methods are insufficient to in themselves identify causation. You need an experimental system—you need a human brain.”
Anand and colleagues used a proprietary method—for which he has filed an invention disclosure with OSU—to convert adult skin cells into pluripotent stem cells that can be programmed to become any tissue. There are currently other teams working on a similar task, with a research team from Austria growing a brain with maturity of a nine-week old fetus in 2013, while many other less complex organs have been grown using stem cells in labs around the world.
As is, the organioid has structures including a spinal cord, all major brain regions, multiple cell types, signaling circuitry, and a retina. The main missing component is a vascular system, Anand noted. MRI has identified functioning neurons, axons, and dendrites, as well as astrocytes, oligodendrocytes, and microglia in the brain organioid, which took about 15 weeks to build.
“If we let it go to 16 or 20 weeks, that might complete it, filling in that 1% of missing genes. We don’t know yet,” Anand said.
Following the creation of the original model, Anand and colleagues have created brain organioids that model Alzheimer’s, Parkinson’s, and autism. With the addition of a pumping blood supply, the model could also be used to study stroke, as well as other neurological conditions including traumatic brain injury and post-traumatic stress disorder.
For now, Anand and colleague Susan McKay plan to commercialize the brain organioid platform through their start-up, NeurXstem, to accelerate its use in drug discovery. Anand also hopes the brain model will be incorporated in the Defense Advanced Research Projects Agency’s (DARPA) Microphysiological Systems program, which is working to develop engineered human tissue that mimics human physiological systems.