Background and Purpose: When house dust mite (HDM), a common allergen, comes into the mucosal membrane, it may stimulate innate immunity. However, the precise role of IL-25 in the development of HDM induced nasal allergic inflammation is still unclear. Therefore, we investigated the role of IL-25 in allergic rhinitis (AR) patients sensitized to HDM.
Methods: To confirm the production of IL-25 in human nasal epithelial cells (HNECs), we cultured and stimulated HNECs. IL-25 expression in the nasal mucosa from control, non-AR (NAR), and HDM sensitized AR was assessed using immunohistochemistry (IHC), double IHC, and quantitative reverse transcription PCR. Correlations between IL-25 and other inflammatory markers were also explored.
Results: An in vitro study was performed and we observed significantly elevated concentrations of IL-25 in the HNEC samples with highest doses of HDM. Nasal tissues from AR patients sensitized to HDM showed significantly higher IL-25 expression, compared to the control or NAR patients. Moreover, we found that the expression of IL-25 in nasal tissues from AR patients sensitized to HDM was positively associated with Th2 immunity markers, such as ECP and GATA3.
Conclusions: IL-25 expression increased with high dose HDM stimulation and it was associated with Th2 immunity markers. Therefore, IL-25 neutralization might offer a new strategy for treating patients with HDM-sensitized AR.