
The dream of using brain organoids to repair actual human brains has taken a baby step closer to reality: Researchers at the University of Pennsylvania have coaxed their tiny, three-dimensional organoids to produce functional neurons with long axons and dendrites — the gray and white matter, respectively — plucked them out, and grew them into fat bundles that might be transplanted into a broken brain.
The scientists, led by neurosurgeon Isaac Chen, have not taken that final step, according to the draft of their study posted on Thursday to bioRxiv, which publishes papers before they have been peer-reviewed, let alone appeared in a scientific journal. But the goal of using cerebral organoids to repair damaged brains has been driving Chen’s research, including when he implanted human cerebral organoids 2 millimeters in diameter into rat brains. The transplanted human tissue became functionally integrated with the rat’s, suggesting that bits of organoid transplanted into a human brain might do the same.