Contact sensitizers elicit a population of natural killer (NK) cells with memory-like functions that reside in the liver. In Immunity, Hornung and colleagues use a model of contact hypersensitivity to show that the establishment of NK cell memory is dependent on the NLRP3 inflammasome. The application of monobenzone onto the skin drives an NK cell–mediated cytotoxic immune response to melanocytes. The hapten-induced NK cells reside in the liver and can transfer long-term monobenzene-specific responses to naive mice. Monobenzone induces the infiltration of macrophages into the skin as well as the recruitment of macrophages with a tissue-resident phenotype to the lymph nodes, and the infiltration of macrophages and NK cells into the skin is dependent on NLRP3 and interleukin 18. Activation of inflammasomes in tissue-resident macrophages is required for both the priming phase and the recall phase of monobenzone-induced memory NK cell responses.

Immunity (7 June 2016) doi:10.1016/j.immuni.2016.05.008