Mesenchymal stem cells derived exosomes promote the expansion of Bregs and alleviate the collagen-induced arthritis

Abstract

Abstract Olfactory ecto-mesenchymal stem cells (OE-MSCs) are a population of cells which has been recognized as a novel resident stem cell type in the olfactory lamina propria. OE-MSCs have been shown to exert their immunosuppressive capacity by modulating T cell responses. However, it remains unclear whether OE-MSCs possess any immunoregulatory functions on regulatory B cells (Bregs). Exosomes are secreted nanosized membrane vesicles that are increasingly implicated as an important communication tool among various cell types. In this study, exosomes derived from olfactory ecto-mesenchymal stem cells (OE-MSCs-Exo) effectively enhanced the proportions of CD19+IL-10+ Bregs in the spleen and draining lymph nodes, thus suppressing the development of collagen-induced arthritis (CIA). In culture, OE-MSCs-Exo could significantly promote the differentiation and expansion of CD19+IL-10+ Bregs, and the further investigation demonstrated that the expansion of Bregs was orchestrated by Ebi3 secreted by exosomes. Taken together, OE-MSCs-Exo have the potential to alleviate the severity of CIA through inducing Bregs, indicating OE-MSCs-Exo may represent a new therapeutic strategy for the treatment of rheumatoid arthritis.