What happens when you implant human glia—a type of brain cell that protects and nurtures neurons—into the brains of newborn mice? Well, it turns out these glia mature into multi-talented astrocyte cells that provide nutrients, repair injuries, and modulate signals just like they do in a human brain. They even assume the same complex star shape!
We know the cells in question are indeed human astrocytes because they produce a group of specific proteins, which are tagged with a combination of dyes that together appear yellow in this image. In contrast, the mouse cells are blue.
This all looks very pretty, but you might wonder what impact these human astrocytes have on mouse cognition. Researchers found mice that received the implants were better able to learn and remember than those that didn’t. In short, the human cells seem to have made the mice smarter.
Interestingly, human astrocytes are larger, more complex, and more diverse than their counterparts in other species. So, perhaps these cells may hold some of the keys to our own unique cognitive abilities.
Forebrain Engraftment by Human Glial Progenitor Cells Enhances Synaptic Plasticity and Learning in Adult Mice. Xiaoning Han, Michael Chen, Fushun Wang, Martha Windrem, Su Wang, Steven Shanz, Qiwu Xu, Nancy Ann Oberheim, Lane Bekar, Sarah Betstadt, Alcino J. Silva, Takahiro Takano, Steven A. Goldman, and Maiken Nedergaard. Cell Stem Cell 12, 342–353, March 7, 2013.
NIH support: the National Institute of Mental Health; and the National Institute of Neurological Disorders and Stroke