By injecting human cells into mouse pups, scientists have created mice whose brains are part human. These hybrid mice grew up to be smarter than their peers, performing much better in tests for memory and cognition. Although this may sound like the plot of a terrible Sci-Fi film, researchers hope to glean a lot of valuable information from these experiments. For example, by studying brain diseases in whole organisms rather than in cells in a dish, researchers should gain a better understanding of how the conditions develop and progress.
For the study, which has been published in The Journal of Neuroscience, researchers from the University of Rochester Medical Center started off by isolating immature glial cells from donated human fetuses. Glial cells are one of the two main cell types that build the nervous system, the other being neurons. Glia perform a variety of roles in the nervous system, such as providing support and protection for neurons, but unlike nerve cells they do not participate directly in electrical signaling, which is a form of communication used to transmit information between cells.