Scientists transplanted human brain cells into live rats and discovered that they connected to the rat’s brain. The rats’ brains integrated the human tissue and put it to work. It wasn’t quite a Frankenstein-esque brain transplant, but it is remarkable progress in the field of lab-grown mini-brains. This gives researchers studying neurological and psychiatric conditions like epilepsy and schizophrenia a way to test out treatments.
This research may have seemed inconceivable just a few years ago. But scientists are now able to grow brain cells, called organoids, from human skin cells. In this study, they injected those into the area of a rat’s brain that processes tactile input like whisker movement. Five months later, the human brain cells had grown and integrated into the rat’s brain. When the scientists blew air across the rat’s whiskers, both the rat’s brain and the human cells lit up. The rats that received the transplant were young, to take advantage of the fact that connections in their brains are still forming.
The peer-reviewed journal Nature published the research, which we read about in The Guardian. The team was made up of scientists from Stanford University, in both the psychiatry and neurology departments. In a press release, they highlighted that the brains transplanted into rats grew much bigger and more complex than they do in the laboratory setting. The connection to blood and sensory input helps the cells develop. The rodents themselves, however, do not grow to an unusual size.
Scientists use similar lab-grown mini-brains in many other research projects around the world. For example, they are crucial to studying the connection between eyes and the brain, as well as treatments for neurodegenerative diseases like ALS.
Melissa is Nerdist’s science & technology staff writer. She also moderates “science of” panels at conventions and co-hosts Star Warsologies, a podcast about science and Star Wars. Follow her on Twitter @melissatruth.