Innate immunity of the sinonasal cavity and its role in chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is one of the most common health problems in the United States. Medical therapy and surgery are successful in treating the majority of patients with sinusitis; however, CRS patients recalcitrant to traditional therapy are increasingly prevalent. Although traditionally this illness could be explained by sinus ostial obstruction and persistent bacterial infection, the rhinologic literature over the years has suggested a significant underlying inflammatory component. Adaptive immune components, including lymphocytes and their associated cytokines, have been the subject of most research in chronic nasal inflammation. A recent appreciation of the importance of the innate immune system is leading to new areas of investigation regarding the pathogenesis of CRS. This review will outline our current knowledge of sinonasal innate immunity, the role of innate immunity in the pathogenesis of CRS, and potential therapeutic targets in the innate immune system.