Thirty years ago, Polly Matzinger introduced the ‘danger theory of immunity’, which proposed that danger and damage have a decisive role in immune responses. In this Perspective, Kroemer et al. reflect on the impact of the danger theory, discuss its molecular foundations and present an extended version of it. They propose that immunological self-tolerance is organized in a hierarchy that functions in a close-to-fail-safe cascade-like fashion, thereby reconciling Matzinger’s danger theory with the self–non-self-discrimination hypothesis.
- Guido Kroemer
- Léa Montégut
- Laurence Zitvogel
