Immunology of Nasal Polyposis and Allergic Rhinitis

Allergic rhinitis and chronic rhinosinusitis with nasal polyps (CRSwNP) represent two common diseases associated with significant morbidity and socioeconomic burden. Both of these diseases are characterized by type 2 inflammatory responses, but the mechanisms that drive each of these diseases appear to be distinct. While allergic rhinitis is driven by multiple cycles of classic early- and late-phase allergic responses, CRSwNP is driven by unknown chronic inflammatory mechanisms. Further studies are needed to elucidate the mechanisms that result in the formation of chronic type 2 inflammatory responses versus classic allergic reactions. Importantly, new tools and/or animal models are needed to aid mechanistic studies in CRSwNP, which would help to address many of these questions and ultimately improve patient care and quality of life. This article will focus on the epidemiology and the current understanding of the immunologic mechanisms associated with each of these diseases.