[The role of Th9, Th17 and Treg cells on pathogenesis of nasal polyps]

To investigate the expression levels of Th9, Th17 and Treg cells in peripheral blood of patients with chronic rhinosinusitis with nasal polyps (CRSwNP), and explore the role of Th9, Th17 and Treg cells in the progression of CRSwNP.

Forty-six cases with CRSwNP served as an experimental group, while 22 cases with simple nasal bleeding or nasal septum deviation served as a control group. The peripheral blood of patients in both groups was collected and analyzed. (1) Using flow cytometry (FCM) to detect the expression rates of Th9, Th17 and Treg cells in peripheral blood. (2) Using qRT-PCR to detect the expression of relevant transcription factor of Th9, Th17 and Treg cells (IL-9mRNA, PU. 1, IRF-4, RoRc, and Foxp3). (3) Using SPSS16.0 to analyse the differentiations and the revelance among these three cells.

(1) The expression rates of Th9 and Th17 cells in patients with CRSwNP (1.29% ± 0.18%, 4.03% ± 0.69%) was higher than the control group (0.45% ± 0.14%, 1.35% ± 0.26%). But the expression rates of Treg cells in the experimental group (2.98% ± 0.13%) was significantly lower than the control group (5.44% ± 0.57%). The differences were statistically significant (P < 0.05). (2) The expression of revelant transcription factor (IL-9mRNA, PU.1, IRF-4, RoRc) in NP group was also higher than the control group. The expression of Foxp3 in the control group was higher than NP, the differences both were statistically significant (P < 0.05). (3) The difference between Th9 and Th17 in patients with NP was not significant (P > 0.05), and the negative correlation was found between Th17 and Treg (r = -0.549, P < 0.05).

The high expression level of Th9 and Th17 cells might promote the development of NP, whereas the low expression level of Treg cells might further aggravate the occurrence of NP. The main function of the imbalance of Th17/Treg cells may be immune regulation in the pathogenesis of nasal polys.