Immune response as a model for the function of evolving systems

In an adaptive immune response, memories of pathogen encounters are encoded by subjecting our own cells to directed evolution. B cells (the cells that make antibodies) enter a competitive arena in lymph nodes called the germinal center, where they mutate a key molecular phenotype: the binding affinity of their antibody protein to an infectious molecule. The germinal center is an evolutionary engine that sifts for cells with rare mutations that improve binding and culls the rest, dynamically seeding our immune cell repertoire with pathogen-responsive lineages that encode our personal history of exposures. In this talk I will discuss recent work synthesizing experimental model systems, data-driven prediction, and theoretical models to infer the evolutionary mechanisms that underpin immune memory encoding. The immune system is an ideal setting to study the function of evolving systems, and fertile ground for theorists to advance biological understanding with novel approaches in dynamical systems, inverse problems, stochastic processes, and interacting particle systems.