Recent studies have identified olfactory ecto-mesenchymal stem cells (OE-MSCs) as a new type of resident stem cell in the olfactory lamina propria. accompanied by reduced Th1/Th17 cell responses with increased Treg cells and findings, we further revealed that the co-culture of na?ve T cells with OE-MSCs promoted the expansion of Treg cells under a polarized condition for Treg differentiation. Although it currently remains unclear how OE-MSCs promote Treg cell differentiation, it is likely that soluble mediators produced by OE-MSCs, such as TGF-, IL-10, and NO may contribute to the functional induction of Treg cells. In particular, it is evident that TGF- plays a non-redundant role in the activation of Foxp3 expression and the expansion of Treg cells. RA is a common autoimmune disease that progressively affects multiple joints with synovial hyperplasia, cartilage destruction, and bone erosion. Although the etiology of RA is still unclear, current strategies for the treatment of RA include the suppression of autoimmune inflammation using newly developed biologics, such as IL-1 receptor antagonists,31 TNF inhibitors,32 and an anti-IL-6 receptor antibody.33 Although these buy 495-31-8 treatments can significantly inhibit the inflammatory response, achieving full remission of disease progression remains a challenge for many RA patients.34 Therefore, it is important to develop more effective therapies for RA. MSCs are a type of stromal cell that are capable of differentiating into cartilage, bone, and other tissues. Other than their clinical applications in regenerative medicine, MSCs have been extensively investigated for their immunosuppressive functions. In the clinical settings, BM-MSCs have been used to treat inflammatory and autoimmune diseases by promoting tissue damage repair and tissue regeneration.35,36 Recent studies have characterized the immunoregulatory functions of MSCs in modulating immune responses that are mediated by various immune cells, such as T- and B lymphocytes and dendritic cells.37 It has been reported that BM-MSCs strongly suppress T-lymphocyte proliferation via mechanisms involved in cellCcell contact and in soluble factor production.38 However, clinical applications of BM-MSCs have encountered difficulties, including the invasive approach that is required for cell harvest and donor age-related limitations.39,40 Because the nasal lamina propria is an easily accessible tissue that can be harvested under local anesthesia,41 OE-MSCs buy 495-31-8 could be collected for autologous transplantation. Moreover, OE-MSCs exhibit a higher proliferation profile than BM-MSCs and can be expanded in culture for therapeutic approaches.12 Considering the advantages of their easy accessibility and efficient expansion for adoptive transfer, OE-MSCs may serve as a possible cellular therapy for RA. In conclusion, we have identified a novel function for OE-MSCs with immunoregulatory properties. Moreover, OE-MSCs could exert their immunosuppressive capacity in modulating T-cell responses and could significantly ameliorate Rabbit Polyclonal to MRPS33 disease severity in CIA mice. These findings suggest that OE-MSCs represent a new potential cell therapy for targeting autoimmune diseases. Acknowledgments This work was supported by grants from the National Natural Science Foundation of China (Grant Nos. 31470881, 81072453), the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20133227110008), the Health Department Foundation of Jiangsu Province (Grant No. Z201312), the Graduate Student Research and the Innovation Program of Jiangsu Province (Grant No. KYLX_1074), the Jiangsu Province 333′ Project (Grant No. BRA2015197), the Priority Academic Program Development of Jiangsu Higher Education Institutions, the National Basic Research Program of China (2014CB541904), and the Hong Kong Croucher Foundation. Notes The authors declare that no buy 495-31-8 conflicts of interest exist..