Researchers at the University of Virginia School of Medicine have made a surprising discovery: the immune system directly impacts – and even controls – creatures’ social behavior, such as, for instance, their inclination to interact with others. The researchers’ findings suggest that immune system problems could potentially contribute to the inability to have normal social interactions, a fact that could have important implications for neurological disorders like schizophrenia.
The brain and the immune system are seen as isolated typically, according to Jonathan Kipnis, the chair of UVA’s Department of Neuroscience. Last year, Kipnis and his collaborators discovered meningeal vessels directly link the lymphatic system with the brain, causing in a paradigm shift in how we think of the relation between the two.
The follow-up study suggests that the relationship between disease-causing organisms and individuals may directly impact the development of social behavior; it may allow us to engage in the social interactions necessary for the survival of the species while developing ways for our immune systems to protect us from the diseases that accompany those interactions.
The research team showed that a specific immune molecule, interferon gamma, appears to be critical for social behavior. Additionally, their findings suggest that a variety of creatures, including flies, zebrafish, mice and rats, activate interferon gamma responses when they are social. This molecule is typically produced by the immune system to respond to bacteria, viruses or parasites. If one blocks the molecule in mice with genetic modification, it made regions of the brain hyperactive, and the mice actually become less social. After the molecule was restored, the mice behavior and brain connectively returned to normal.
The findings suggest that the molecule, interferon gamma, has been used in order to efficiently boost an anti-pathogen response and social behavior. The team also noted a malfunctioning immune system could be a cause of social deficits. Further research is needed to understand what this might mean for autism and other specific conditions requires further investigation.
Their discovery that the immune system – and potentially pathogens, by extension – have the ability to control our interactions raises questions and reflection, both in terms of understanding human behavior and battling neurological disorders.
For more information, please visit: https://news.virginia.edu/.