Changes among TGF-β1+ Breg cells and helper T cell subsets in a murine model of allergic rhinitis with prolonged OVA challenge

Abstract

BackgroundAllergic rhinitis is a common allergic disease resulting from inappropriate Th2 cell-mediated immune responses to environmental antigens. As such, regulatory B cells and T helper cells play a critical role in the occurrence and development of allergic rhinitis. MethodsWild-type mice received ovalbumin (OVA) intranasal challenge for varied lengths of time, then the inflammatory state of their nasal mucosa was analyzed by histology. Changes to the proportion and function of TGF-β1+ Bregs, T helper cells and plasma cells was analyzed by flow cytometry, real-time PCR, ELISA and cytometric bead arrays. Finally, changes in expression of upstream transcription factors related to helper T cells and STAT proteins were detected by western blot. ResultsThe most severe inflammatory response was observed in the mucosal tissue, where the percentage of TGF-β1+ Bregs and Tregs decreased, and the percentage and function of Th2 and plasma cells increased significantly. With prolonged OVA challenge, the proportion of TGF-β1+ Bregs and Tregs increased. These factors regulated Th2 cell polarization state and gradually restored balance of the inflammatory state in the nasal mucosa. Moreover, changes to upstream transcription factors and STAT proteins were found to be positively correlated with changes to helper T cells. ConclusionTGF-β1+ Bregs cooperated with Treg cells in the development of allergic rhinitis and its recovery process. Reconstitution of nasal mucosal immunity was facilitated via regulation of the proportion and function of helper T cells.