Treg cells prevent autoimmunity during infections, research finds

New research from the University of Chicago reveals how certain immune cells help prevent the body from attacking itself during infections. These findings may lead to new treatments for autoimmune diseases. When the body is infected, the immune system must tell the difference between harmful invaders and its own cells. If it fails, the immune system can mistakenly target healthy tissues, causing long-term damage. The study highlights a group of immune cells known as regulatory T cells (Tregs), which act like peacekeepers to prevent this friendly fire. Researchers found that Tregs have the ability to recognize specific proteins, or antigens, from the body's own tissues. They help stop other immune cells, called helper T cells, from overreacting to these self-antigens. This balancing act is crucial during infections when the body also needs to combat pathogens. In their experiments, the team temporarily removed Tregs from mice that were designed to recognize a specific self-antigen from the prostate. Without these Tregs, the helper T cells attacked the prostate when the mice were exposed to an infection, leading to autoimmune reactions. Interestingly, the helper T cells remained effective in fighting the bacterial infection, showing that Tregs do not hinder the immune response when distinguishing between self and non-self antigens. The researchers pointed out that instead of completely removing all helper T cells that may react to self-ants, maintaining a sufficient number of Treg cells can effectively prevent autoimmune responses while still allowing the body to fight infections. This study opens the door for new approaches to manage autoimmune conditions.