IL9 and Alzheimer disease: Considering that S. aureus sensitization is frequent in HDM-sensitized AD patients [47] and SEB facilitates allergen-specific Th2 responses [48], assessing the possible synergic effect of HDM and SEB to trigger IL-9 response as well as exploring whether other allergens and S. aureus toxins could induce a memory T-cell response in our model remains a limitation in this study.