Social behavior may have immune connection

Abstract

Our brains—and those of other social creatures—have circuitry that helps us navigate our interactions with other people. A new study suggests that these circuits might receive input from the immune system. Researchers led by Jonathan Kipnis of the University of Virginia report that a protein released by certain immune cells can influence social behavior in mice (Nature 2016, DOI: 10.1038/nature18626). The findings, the scientists say, could someday help identify disrupted immune pathways involved in neurological disorders that affect social behavior, such as autism and schizophrenia. In the study, Kipnis and his colleagues impaired the immune systems of mice so that the animals lacked mature T cells. These mice weren’t social, performing similarly to mice with autismlike conditions in tests of social behavior. T cells aren’t present in healthy brains. So the scientists wondered how the cells could exert influence on neurons without directly interacting with them. They looked for a