In this study, T cell plasticity and survival and the role of different damage-associated molecular patterns, prostaglandins, and bacterial superantigens in chronic rhinosinusitis will be studed. The role of the specific mucosal milieu on T cell plasticity will be analyzed in vitro, in vio in Rag2-/-γc-/- knockout mice transplanted with human inflamed mucosa, and ex vivo in human nasal mucosal tissue.