Breakthrough UC study sheds light on survival of new neurons in adult brain

The study, recently published in the journal Nature Communications (NOTE: WILL INCLUDE LINK), is leading to a new understanding of how immune cells can influence  adult neurogenesis, the process of creating new neurons in the brain. Neurons are the brain's fundamental information messengers, and the immune cells conduct surveillance and send messages to new neurons.

The study’s corresponding author is Yu (Agnes) Luo, PhD, professor and vice chair for research in the Department of Molecular and Cellular Biosciences.

“Adult neurogenesis is vital for learning, memory and mood regulation, and we hope to discover novel ways to enhance this process,” said Luo. Factors such as exercise, sleep and learning can stimulate neurogenesis, while stress and aging can decrease it — offering one possible explanation for cognitive decline.

Luo said it has long been debated whether adults even have the capacity for neurogenesis. Does the human brain make new neurons in adulthood?

Then research published in the journal Science in the summer of 2025 concluded, yes, neurogenesis happens in the adult human hippocampus, the part of the brain that handles learning and memory.

So Luo and the graduate assistants working in her research lab on UC’s campus turned their attention to the mechanisms that regulate adult neurogenesis, and their research in Nature Communications reveals two breakthroughs.

The first is that immune cells in the brain, known as microglia, have the capacity to  regulate neurogenesis in the hippocampal region of the adult brain. 

“The status of microglia in the hippocampus is critical in the process,” said Luo.

The second breakthrough concerns activated microglia, which lack TGF-beta signaling, and, in turn, stimulate adult neurogenesis through microglia-neural stem cell signaling crosstalk — the complex interplay in which cellular pathways communicate.

For now, research on adult neurogenesis has been in animal models, but microglia-integrated human organoids are in development for future testing. For the human organoids, Luo is working with Ziyuan Guo, PhD, assistant professor in the College of Medicine’s Department of Pediatrics. Guo’s lab at Cincinnati Children’s focuses on developing next-generation human central nervous system (CNS) models to study neurodevelopmental and neurodegenerative disorders using advanced stem cell and engineering technology.

Krishna Roskin, PhD, an informaticist and immunobiologist at Cincinnati Children’s, also helped decipher the immune-neural stem cell crosstalk by single-cell RNA sequencing analysis.  

A long-term goal of Luo and her lab is to use adult neurogenesis as rejuvenation in the brains of aging adults, helping to sustain their cognition and allowing for healthier aging.

“We are training the next generation of scientists here at the UC College of Medicine,” said Luo.

Others from the Luo lab at UC who contributed to the research include Alicia Bedolla, Claire Distel, Aleksandr Taranov and Jake Yazell.

Contributors from outside UC include Shane Liddelow at the NYU Grossman School of Medicine; Christina Thapa at the Center for Psychiatric Genetics in Evanston, Illinois, a partnership between UChicago Medicine and NorthShore University HealthSystem; Sven Lammich at the Biomedical Center Munich in Germany; and Alice Sülzen and Regina Feederle at the German Center for Neurodegenerative Diseases in Munich.

Featured image at top: Yu (Agnes) Luo, PhD, standing on a bridgeway in the CARE/Crawley building atrium. Photo/UC Marketing + Brand.