Th17/Treg balance in children with obstructive sleep apnea syndrome and the relationship with allergic rhinitis

Objective: This study aims to explore the role of the Th17 to Treg cell ratio in children with USA and its relationship with allergic rhinitis. Methods: The study included 127 children diagnosed with USA by polysomnography (PSG) testing and 29 children without USA. The 127 children with USA were divided into the following groups: USA with moderate adenoidal hypertrophy (n = 47), USA with severe adenoidal hypertrophy (n = 49), and USA complicated by allergic rhinitis (AR) (n = 31). The adenoids of the 29 children without USA were mildly hypertrophic. We measured the number of Th17 and Treg cells, the levels of related serum cytokines in cellular secretions, and the expression of key transcription factors in both the peripheral blood and adenoid tissue. The Th17/Treg ratio was calculated and analyzed between groups. The numbers of Th17 and Treg cells were measured by flow cytometry; the secreted IL-17, IL-10, and TGF-beta were measured by ELISA; and the expression levels of ROR gamma t and Foxp3 were measured by RT-PCR. Results: Compared with the control group, USA children exhibited a significant increase in the number of peripheral Th17 cells, Th17-related cytokine secretion (IL-17), and ROR gamma t mRNA levels, whereas they exhibited a decrease in the number of Treg cells, Treg-related cytokine secretions (IL-10, TGF-beta) and Foxp3 mRNA levels. The Th17/Treg ratio was higher (p < 0.05) in the USA groups than in the control group. The Th17/Treg ratio was correlated with the size of the adenoids. We also found that the Th17/Treg balance in USA patients was complicated by allergic rhinitis; the increase was significantly larger in the AR group (p < 0.05, p = 0.021) than in USA groups without AR. These results were observed in both the peripheral blood and local adenoid tissue. Conclusion: The Th17/Treg imbalance may increase the risk of developing USA, and AR may promote the development of the disease. These results provide an alternative explanation for USA pathogenesis that warrants additional research and presents new directions for the prevention and treatment of USA in children. (C) 2015 Elsevier Ireland Ltd. All rights reserved.