Pattern recognition receptor function in neutrophils

Previously, neutrophils were largely ignored in the pattern recognition receptor (PRR) signaling field. However, interest in neutrophil biology has been revitalized by emerging roles for neutrophils in promoting protective and pathogenic T helper (Th)17-driven immune responses and in orchestrating innate and adaptive immunity via cytokine/chemokine production. Although it was originally assumed that neutrophils are transcriptionally inert and their short lifespan limits their ability to respond to PRR agonists, the past 5 years has seen tremendous advances in neutrophil PRR signaling that have shifted this paradigm. Here, we review recent findings that demonstrate that neutrophils express a broad repertoire of PRRs, respond dynamically to their stimulation during infection and inflammation, and that neutrophil PRRs are key regulators of in vivo host immune responses.