Innate signaling in the inflammatory immune disorders.

Pattern recognition receptors (PRRs) of innate immune cells recognize the conserved molecular signatures on pathogens, termed pathogen-associated molecular patterns. PRRs also recognize endogenous damage-associated molecular patterns. Following pathogen infection or tissue damage, the stimulation of PRRs activates distinct but shared signaling pathways that lead to effector mechanisms in innate host defense. PRR signaling is strictly and finely tuned to ensure the appropriate duration and strength to prevent damaging inflammation to the host. Here we attempt to provide a brief background on the agonists and signal transduction pathways of PRRs and summarize the mechanisms underlying the control of PRR signaling, with a particular focus on the recent progress of the involvement of PRR signaling in the inflammatory immune disorders.