Discussion
sinusitis, asthma, allergic disease
SINUSITIS, ASTHMA, CONCOMITANT DISEASE
SLIT, as the best treatment with the ability to modify the course of allergic disease, has been recommended as the first-line therapy for AR by several guidelines lately [To further determine the effect of SLIT on the ILC2 milieu, the present study stimulated PBMCs from patients after 1- and 2-year SLIT treatment by HDM and ILC2-stimulating factor (TSLP, IL-33, IL-25) and then detected the changes in ILC2 and related cytokines. The data showed that after 2-year SLIT treatment, HDM and stimulating factors did not induce significant activation of the ILC2 milieu, such as increased ILC2 frequency and high expressed cytokine levels in the SLIT group. However, there was an opposite result in the control group. In this group, the intervention led to a significant increase in the levels of ILC2 milieu-related indicators, and a positive correlation was observed between the ILC2 frequency and expression of inflammatory cytokines (IL-5/IL-13). These data clarified the regulatory effect of SLIT on the ILC2 milieu in PBMCs and the role of ILC2 in the regulation of Th2 cytokines in AR. The ability of ILC2 to promote Th2 cytokine production in PBMCs was significantly reduced after 2-year SLIT, suggesting that the regulatory function of SLIT on ILC2 is one of the pathways to improve Th2 bias in immunotherapy.Children with AR often experience sinusitis, asthma, or other related concomitant diseases [In conclusion, the data of the present study indicated that expression of ILC2 milieu-related indicators decreased after SLIT, and these low expression levels were maintained for at least 2 years. The reduced activation capacity of the ILC2 milieu is related to SLIT. These data suggest that ILC2s may be involved in SLIT, which partly explains the mechanism by which SLIT reduces the Th2 reaction. However, our study offers only a preliminary investigation of the role of ILC2 in SLIT. The sample size of present study is small, and the changes in immunity over a longer period after the end of treatment have not been observed. In the future, it is necessary to further study the specific signal pathway mechanism of SLIT on the changes of ILC2 cells, so as to further elucidate the therapeutic mechanism. Moreover, with further research, the changes of ILC2 might be considered as a potential predictor of SLIT curative effect evaluation.