New cell therapy improves memory and stops seizures after brain injury

A breakthrough cell therapy to improve memory and prevent seizures in mice following traumatic brain injury (TBI) has been developed by researchers.

In the study, the research team from the University of California, US transplanted embryonic progenitor cells capable of generating inhibitory interneurons (a specific type of nerve cell that controls the activity of brain circuits) into the brains of mice with traumatic brain injury, targeting the hippocampus.

These are transplanted inhibitory neurons (green) successfully incorporated into the hippocampus of a mouse with traumatic brain injury (credit: UCI School of Medicine).

The researchers discovered that the transplanted neurons migrated into the injury where they formed new connections with the injured brain cells and thrived long term. Within a month after the treatment, the mice models showed signs of memory improvement.

The cell transplants also prevented the mice from developing epilepsy, which affected more than half of the mice who were not treated with new interneurons.

“Inhibitory neurons are critically involved in many aspects of memory, and they are extremely vulnerable to dying after a brain injury,” said Robert Hunt, PhD, assistant professor of anatomy and neurobiology at UCI School of Medicine who led the study. “While we cannot stop interneurons from dying, it was exciting to find that we can replace them and rebuild their circuits.”

To further test their observations, the team silenced the transplanted neurons with a drug, which caused the memory problems to return.

“It was exciting to see the animals’ memory problems come back after we silenced the transplanted cells, because it showed that the new neurons really were the reason for the memory improvement,” added Bingyao Zhu, a junior specialist and first author of the study.

“So far, nobody has been able to convincingly create the same types of interneurons from human pluripotent stem cells,” Hunt concluded. “But I think we’re close to being able to do this.”

The study was published in Nature Communications.