Human Umbilical Cord-Derived Mesenchymal Stem Cells Downregulate Inflammatory Responses by Shifting the Treg/Th17 Profile in Experimental Colitis

<b><i>Background/Aims:</i></b> The aim of this study was to evaluate the effect and mechanisms of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) on immune responses in murine colitis. <b><i>Methods:</i></b> Mice with dextran sulfate sodium (DSS)-induced colitis were injected intraperitoneally with hUC-MSCs or human bone marrow-derived MSCs. The cytokine levels from lamina propria mononuclear cells (LPMCs) and colon tissue were measured using ELISA. Treg and Th17 cells were analyzed using flow cytometry. The proliferation of LPMCs was assessed using Cell Counting Kit-8. <b><i>Results:</i></b> hUC-MSCs ameliorate DSS-induced colitis via the downregulation of colon inflammatory responses. Furthermore, hUC-MSCs adjusted modulation of Treg/Th17 cells in the spleen and mesenteric lymph nodes. hUC-MSCs also inhibited LPMCs in vitro<i>.</i><b><i>Conclusion:</i></b> hUC-MSCs may be an alternative source of stem cells and are worthy of study in long-term clinical trials.