Fig. 4

Umbilical cord–derived mesenchymal stem cells (UC-MSCs) suppress CD4⁺ T-cell proliferation as well as T helper 1 (Th1) and Th17 cell differentiation via galectin-9. a Carboxyfluorescein diacetate succinimidyl ester (CFSE)–labeled CD4⁺ T cells were cultured in the presence of UC-MSCs or UC-MSCs plus α-lactose for 4 days. The proliferation of murine CD4⁺ T cells was assessed on the basis of the fluorescence intensity of CFSE. Bars represent the mean ± standard error of the mean (SEM); n = 3 per group. b Purified naïve murine CD4⁺ T cells were cultured under Th1 polarization conditions in the presence of UC-MSCs or UC-MSCs plus α-lactose. Representative flow cytometric profiles that show the frequencies of Th1 cells are presented. The frequencies of Th1 cells were quantified. c Purified naïve murine CD4⁺ T cells were cultured under Th17 polarization conditions in the presence of UC-MSCs or UC-MSCs plus α-lactose. Representative flow cytometric profiles that show the frequencies of Th17 cells are presented. The frequencies of Th17 cells were quantified. Bars represent the mean ± SEM; n = 4 per group. *P <0.05, **P <0.01, ***P <0.001