PT - JOURNAL ARTICLE AU - Andreas Mayer AU - Thierry Mora AU - Olivier Rivoire AU - Aleksandra M. Walczak TI - Diversity of immune strategies explained by adaptation to pathogen statistics AID - 10.1101/033159 DP - 2015 Jan 01 TA - bioRxiv PG - 033159 4099 - http://biorxiv.org/content/early/2015/11/27/033159.short 4100 - http://biorxiv.org/content/early/2015/11/27/033159.full AB - Biological organisms have evolved a wide range of immune mechanisms to defend themselves against pathogens. Beyond molecular details, these mechanisms differ in how protection is acquired, processed and passed on to subsequent generations – differences that may be essential to long-term survival. Here, we introduce a mathematical framework to compare the long-term adaptation of populations as a function of the pathogen dynamics that they experience and of the immune strategy that they adopt. We find that the two key determinants of an optimal immune strategy are the frequency and the characteristic timescale of the pathogens. Depending on these two parameters, our framework identifies distinct modes of immunity, including adaptive, innate, bet-hedging and CRISPR-like immunities, which recapitulate the diversity of natural immune systems.