METHODS: The mRNA of TRPV1 and proinflammatory cytokines such as IL-4, 6, 8, 13, 25, 33, TNF-α and IL-1β was determined by real-time quantitative PCR. ELISA of TRPV1 was performed using NLFs and induced sputum of the patients with CRS, asthma, and normal controls, respectively.
RESULTS: TRPV1 expression was significantly increased in patients with asthma compared with healthy controls using ELISA of sputum supernatants. There was a significant correlation between TRPV1 and IL-4, 25, 33, and TSLP mRNA expression in sputum of asthmatics. In patients with CRS without asthma, TRPV1 tended to be increased in NLF compared to that of controls. TRPV1 also correlated with IL-25, 33, and TSLP mRNA in CRS patients. However, there was no meaningful association between TRPV1 level and the severity of asthma or CRS.
CONCLUSIONS: TRPV1 expression was increased in both CRS and asthma patients. The degree of TPRV1 expression was commonly associated with epithelial driven and Th2 cytokines in both upper and lower airways, suggesting that TRPV1 may be involved in innate Th2 inflammation.