01 · The discovery
The idea, in everyday language
An immune system must fight threats without destroying the body. Removing some dangerous cells early in their development is not enough: immune responses also need active restraint in the rest of the body.
Sakaguchi identified regulatory T cells that provide that restraint. Brunkow and Ramsdell linked a severe immune disorder to the gene Foxp3. The connection between Foxp3 and regulatory T cells helped explain a central mechanism of peripheral immune tolerance.
Why it matters
These discoveries guide research into autoimmune disease, transplantation and cancer, where the desired direction of immune regulation may differ.
