Conditioned medium from the bone marrow mesenchymal stem cells modulates immune response via signal transduction and activator of transcription 6 signaling pathway in an allergic rhinitis mouse model

ABSTRACT

Background: Allergic rhinitis (AR) is a common immune disease of the nasal mucosa character-ized with immunoglobulin E (IgE)-mediated allergic inflammation after exposure to allergens in susceptible population. Previous reports have demonstrated that the bone marrow mesenchy-mal stem cells (BMSCs) could reduce allergic inflammation. However, there is little knowledge about whether the culture supernatant of BMSCs (conditioned medium, CM) has similar anti-inflammatory potential in treating AR. Objective: The study aimed to evaluate the immunoregulatory effects of conditioned medium derived from BMSCs (BMSC-CM) on allergic inflammation in an AR mouse model.Material and Methods: The AR murine model was induced by repeated sensitization and chal-lenges with ovalbumin (OVA). Subsequently the allergic symptoms of AR mice, cytokine levels, the histopathological features of the nasal mucosa and T helper 1 (Th1) T helper 2 (Th2) cells ratio were evaluated.Results: Treatment with BMSC-CM was found as effective as BMSCs in reducing allergic symp-toms and inhibiting eosinophilic infiltration in the nasal mucosa. After BMSC-CM or BMSCs administration, the OVA-specific IgE and interleukin 4 levels in serum decreased and interferon gamma level increased compared with AR mice treated with uncultured fresh medium. Flow cytometry analysis revealed a decrease in Th1Th2 cells ratio after OVA-sensitization and the ratio was reversed by BMSC-CM and BMSCs treatments. Furthermore, the data revealed that BMSC-CM suppressed the production of signal transduction and activator of transcription 6 (STAT6) at messenger RNA and protein levels in the nasal mucosa (AU)