Nasal instillation of probiotic extracts inhibits experimental allergic rhinitis.

Allergic rhinitis (AR) is a common disease. The therapeutic efficacy of AR needs to be improved. This study aims to evaluate the effects of local administration of probiotic extracts on inhibiting experimental AR. Epithelial cells (ECs) were primed by exposing to extracts (CBe) in the culture to upregulate the expression of IL-10. A mouse AR model was developed to assess the therapeutic potential of CBe in AR. CBe markedly induced the expression of IL-10 in ECs. Co-culture of naive B cells with CBe-primed ECs significantly increased IL-10 expression in the B cells (iB10 cells). The iB10 cells showed immune suppressive function in suppressing effector CD4 T-cell proliferation. Treatment with nasal drops containing CBe efficiently inhibited experimental AR in mice. Local administration of CBe can efficiently inhibit experimental AR.