Changes in behavior that may indicate infection are identified. Reedus

When a person falls ill, his behavior changes, even if he himself does not yet suspect that he has some kind of infection.

Scientists from the University of Washington School of Medicine (USA) found this in their recent study thanks to experiments on mice.

In his work, published in журнале Nature Immunology, the researchers found that elements of the immune system affect not only the body, but also the mind, and the immune molecule IL-17 may be a key link connecting the immune system and the brain, which may affect human behavior in dangerous situations, causing alarm.

IL-17 is a cytokine, a signaling molecule that drives the immune response to infection by activating and targeting immune cells. In the brain, IL-17 is produced by gamma delta T cells, which are found in the tissues surrounding the gray matter.

To find out exactly how the IL-17 molecules, as well as the gamma delta T cells that produce them, could influence behavior, the researchers conducted tests in mice. They studied memory, social behavior, foraging, and anxiety in laboratory animals.

It was found that mice lacking gamma delta T cells or IL-17 were indistinguishable from mice with normal immune systems (i.e., gamma delta T cells or IL-17) in all parameters other than anxiety. Mice with normal immune systems were more wary and more concerned about their survival during the tests.

Although the researchers did not expose mice to bacteria or viruses to directly study the effects of infection, they were injected with lipopolysaccharide, a bacterial product that elicits a strong immune response. Gamma delta T cells in response to injection of lipopolysaccharide began to produce more IL-17; however, when the mice were treated with antibiotics, the amount of IL-17 decreased. This suggests that gamma delta T cells can detect the presence of different types of bacteria (beneficial and harmful) and respond to them, including inducing appropriate behavior (anxiety, anxiety).

The existence of specific molecules for simultaneous immunological and behavioral protection is a reasonable evolutionary way to protect the body from infection, – concludes Alves de Lima, one of the authors of the study.

Earlier, “Reedus” talked about how self-isolation affects immunity.

–