Scientists are creating mini brains from human stem cells that will help researchers figure out how to repair the nervous system after injury or disease.
Neuroscientist Robert Krencik, Ph.D. from the Houston Methodist Research Institute is leading the research to grow the brain models. The mini brains will let scientists test drug and treatments and help them find the cause of disease-causing mutations. Dr. Krenick describes the research saying: “We always felt like what we were doing in the lab was not precisely modeling how the cells act within the human brain. So, for the first time, when we put these cells together systematically, they dramatically changed their morphological complexity, size and shape. They look like cells as you would see them within the human brain, so now we can study cells in the lab in a more natural environment.”
Brain model allows scientist to test more quickly
The research is important because it allows scientists to look at how the brain reacts in a more stable and natural way. Just the same way an architect builds a scale model of a future building to test proportions, having the mini brain models lets the scientists see the brain in its complete complex form. Having this clearer picture will speed up brain research and testing. “Normally, growing these 3-D mini brains takes months and years to develop,” Krencik said. “We have new techniques to pre-mature the cells separately and then combine them, and we found that within a few weeks they’re able to form mature interactions with each other. So, the length of time to get to that endpoint for studies is dramatically reduced with our system.”
To create the models the scientist focused on the cell type, astrocytes, which are the key players in getting the brain’s neurons to connect and talk to each other. The cells do this by helping to increase the number and strength of neuronal connections in the brain and spinal cord. These star-shaped cell types are involved in most neural diseases and also are responsible for maintaining a healthy nervous system. The addition of astrocytes accelerated the connections of the surrounding neurons into the brain models. When introducing the research in his published paper, Krencik’s group has dubbed these bioengineered mini brains “asteroids” to differentiate the models from other bioengineered brains that do not contain astrocytes which are known as organoids.
“Using our system, we can generate mature astrocytes and have them interact intimately with neurons to a greater extent than has been done before,” Krencik said. “Unlike other cells in the brain and in the rest of the body, astrocytes have unique properties in humans. It’s thought they are partly responsible for the unique cognitive functions of humans and also may underlie aspects of human diseases, such as Alzheimer’s and autism spectrum disorders.” Their findings are described in an article titled “Systematic three-dimensional coculture rapidly recapitulates interactions between human neurons and astrocytes,” in the Dec. 12 issue of Stem Cell Reports.