RESUMEN
OBJECTIVE@#To investigate the expression and role of Interleukin-33 (IL-33) and ST2 in the nasal polyps of human Eosinophilic and non-Eosinophilic chronic rhinosinusitis with nasal polyps (ECRS and non-ECRS).@*METHOD@#IL-33 and ST2 protein expression in nasal polyps of ECRS and non-ECRS as well as in seemingly normal mucosa of the inferior turbinate tissue was investigated by immunohistochemical staining and messenger RNA (mRNA) expression of IL-33 and ST2 was assessed by realtime polymerase chain reaction (PCR) in 27 subjects with ECRS, 33 subjects with non-ECRS, and 11 control subjects.@*RESULT@#(1) The ST2 was found both in nasal polyps of ECRS and non-ECRS,especially in ECRS, yet hardly found in the normal mucosa of the inferior turbinate tissue; (2) The expression of ST2 mRNA in nasal polyps of ECRS was higher than that in non-ECRS and normal inferior turbinate tissue, and the difference was both prominent in statistics (P0.05).@*CONCLUSION@#The IL-33 and its receptor ST2 were both expressed in human nasal polyps including ECRS and non-ECRS, meanwhile the expression patterns of ST2 at both mRNA and protein levels were significantly higher in nasal polyps of ECRS. The current study suggests that IL-33 and its receptor ST2 may play important roles in the pathogenesis of chronic rhinosinusitis with nasal polyps, especially in ECRS through the increased expression of ST2 in Eosinophils as a hypothesis.