Tufts researchers have created a brain - or at least brain-like structure.
Researchers announced that they developed a three-dimensional model with brain-like cortical tissue that has biochemical and electrophysiological responses. This brain can function normally and provide a new method of understanding brain networks.
The research is reported in Proceedings of the National Academy of Sciences (PNAS).
The researchers did not reconstruct the entire brain network, but instead included the features most relevant to physiological functions.
"This model provides a unique opportunity for mapping out real-time neurophysiological events and function studies in the laboratory, monitoring that is prohibitive with humans or animals," said Philip Haydon, study co-author.
The model looks like a mix of six colorful, doughnut-shaped rings. This mimics the six layers of human brain cortex. It consists of two types of materials: a stiffer porous scaffold and a softer collagen gel matrix. The stiffer material is attuned to cortical neurons and helps maintain stability.
"The tissue maintained viability for at least nine weeks - significantly longer than cultures made of collagen or hydrogel alone - and also offered structural support for network connectivity that is crucial for brain activity," said study first-author Min Tang-Schomer.
This period of time is longer than the two to three weeks for which other synthetic brain tissues have been viable.
The model was seeded with rat cells, and the brain cells that grew on the model passed along electrical signals as they would in a rat's brain.
One of the key ways this model could be used is to observe traumatic brain injury. It could track tissue response to traumatic brain injury including long term effects and repair.
According to the press release, when a weight was dropped on the model's tissue, the tissue released high levels of glutamate, a neurotransmitter that is emitted from brain cells following brain damage. Additionally, the tissue also showed the correct electrical response to traumatic brain injury as well.
Previously, brain tissue could only be grown flat, in petri dishes. Additionally, just having the room to grow didn't help the cells; although the neurons would grow in the appropriate medium, the structures didn't survive long or provide an accurate model of a real brain.
