How Immunity Works

The immune system recognizes viruses and harmful bacteria, destroys them, and protects the body. However, this well-coordinated mechanism occasionally malfunctions. When that happens, the immune system begins to attack the body’s own cells—leading to a range of dangerous autoimmune diseases. Peripheral immune tolerance is the mechanism that allows the immune system to fight off enemies without turning its aggression toward its own tissues. In other words, it teaches the body not to mistake healthy cells for a threat.

To Kill or to Spare

Microbes that threaten our health come in many shapes and forms. Many of them even mimic human cells as a form of camouflage. That’s why scientists worked to uncover how exactly the immune system knows which cells to attack and which cells to protect. The Nobel laureates managed to do just that by identifying the “guards” of the immune system—regulatory T cells. This discovery has paved the way for the development of potentially effective treatments for autoimmune diseases and cancer that are now being evaluated in clinical trials. These innovative findings may also help prevent severe complications after stem cell transplants, marking a major step toward truly controlling the immune system for better health outcomes.

14 October 2025