Every year, 15,000 – 20,000 Americans sustain a spinal cord injury (SCI). Another 200,000 – 500,000 are living in the chronic stages of SCI every day. Loss of movement and sensation, persistent pain, and depression are common. Could stem cells play a role in finding a cure? Dr. Mark Tuszynski shares his work using neural stem cells to build bridges after an SCI – forming new relays across injury sites in the hopes of restoring limb function and feeling. Bob Yant, who suffered an SCI in 1981, joins Tuszynski to express the need for further research in the field of regenerative medicine and to share his story of living with and SCI.
But while other brains are social – no other brain is as social, or can do what the human brain can – and as far as science knows – it also seems that no other brain can suffer from conditions like autism. Are these two fortunes somehow linked?
That is a question that many are asking, including Alysson Muotri’s lab at the Sanford Consortium for Regenerative Medicine. They are using brain organoids to unravel this mystery, but where do they start looking for the root causes of these conditions?
Enter Katerina Semendeferi, noted biological anthropologist, whose experience conducting neuroanatomical comparisons of our primate predecessors, as well as typical and atypical human neuroanatomy, is helping to focus the search for causes of atypical behavioral conditions like autism and Williams Syndrome. Her work has pointed to neuroanatomical differences, on scales from whole brain structures, down to individual neurons and the genetics of neurodevelopment.
She reveals what she has found, and how this helps the Muotri Lab’s studies with brain organoids in the search for autism in our social brains.
Inside a lab at the Sanford Consortium for Regenerative Medicine, researchers are doing something truly remarkable. They are growing tiny versions of developing human brains in order to study everything from Alzheimer’s disease to the Zika virus. Alysson Muotri is the co-director of the UC San Diego Stem Cell Program and leads the team researching brain organoids. He recently sat down with Dr. David Granet on Health Matters to discuss the endless possibilities of his research.
Muotri’s organoids are often referred to as “mini-brains,” but they are far from what that name might suggest. The organoids are grown from stem cells, which are harvested from living tissue, such as skin cells. Researchers give those stem cells instructions to become neural cells. Eventually they form tiny clusters of neural cells, about the size of a pea. Those clusters have been shown to exhibit some of the same characteristics of developing human brains, including firing electrical signals in specific patterns. But, the organoids do not contain every type of brain tissue, and have no vascularization.
Despite the differences with the human brain, organoids have proven useful in understanding and treating disease. One of the major successes of Muotri’s research was finding and testing an existing drug to treat mothers infected with Zika virus. The drug can prevent the disease from being passed to the baby and causing microcephaly. Muotri is hoping his lab will continue to have success using the organoids as an effective brain model to find more cures, and provide a deeper understanding of brain development and disease. And, his work isn’t limited to Earth. Muotri recently launched his organoids into space for a groundbreaking study.
Transplants are expensive and risky, and donor organs are in short supply. Researchers at UC San Diego are working on technology to change all of that. It’s called bioprinting. In simple terms, bioprinting is 3D printing with living tissue. Researcher Shaochen Chen has been perfecting the process in his lab for years.
Bioprinting is a complex process that takes place in a matter of seconds right before your eyes. Chen’s lab builds their own printing machines, which shine light into a gel the team has developed. Any spot the light hits becomes solid. Because the process uses light, it allows the team to recreate microscopic structures like liver cells or vascular networks with incredible precision.
While the process enables researchers to accurately reproduce biological structures, it’s what’s inside the gel that makes bioprinting truly remarkable. The gel can be filled with stem cells from a potential transplant recipient. Those cells can fuse with tissue in the body as the gel disintegrates, essentially repairing damage with the patient’s own cells. Chen’s lab has shown the process can work in rats with severe spinal cord injuries. Someday, the process could be used in humans to do the same.
Bioprinting is also helpful to researchers in other fields. Chen has teamed up with Alysson Muotri and Karl Wahlin to help them study the connection between the eye and the brain. Their labs are conducting research using organoids – tiny organ-like structures grown from stem cells. They realized in order to effectively study how brain and retinal organoids interact with one another, they need to physically separate them at just the right distance, similar to how they might be separated in the womb. Chen’s lab developed a bioprinted structure to achieve that separation, taking the partnership to the next level.
It sounds like the plot of a science fiction movie. Scientists grow brains in a lab and use them to power robots. But, it’s really happening at UC San Diego – to a degree. Stem cell researcher Alysson Muotri has teamed up with a high school student for the groundbreaking project. It’s called the Neurobot, and it’s really cool.
It all started thanks to a high school student with a lot of talent and initiative. Christopher Caligiuri read about the work the Muotri lab was doing with brain organoids and wanted to get involved. He reached out and said he would love to help, and had some experience in robotics if that was useful. Muotri not only agreed, he put the sophomore on a pretty impressive project.
To understand how the Neurobot works, you have to understand the basics of the Muotri lab’s brain organoid research. Brain organoids are clusters of brain cells grown in the lab from human stem cells. They don’t contain every type of brain cell, nor do they have the all the various structures of full-fledged brains. They certainly aren’t capable of independent thought. But, they do give off electrical signals, similar to those of a developing fetus.
The team is using those signals to control the Neurobot. Researchers in the Muotri lab collect and record signal data from the organoids. That data is then fed into the robot through software Caligiuri developed. The software interprets the data as a speed commands, which control how fast the Neurobot walks. If you think it sounds cool, you have to see it in action.