Fig. 2

hUC-EVs-ATO modulated T cell populations in mice with aGVHD but not in vitro. On day 14 after transplantation, the frequencies of IFN-γ⁺CD4⁺ (A), IL-17⁺CD4⁺ (B) and Tregs (C) in the liver and spleen of aGVHD mice treated with PBS, ATO, hUC-EVs or hUC-EVs-ATO were tested by flow cytometry. Data are the means ± SEM of six mice per group. (D) CD4⁺ T cells were immunomagnetically sorted from the spleens of C57BL/6 mice. The purity of CD4⁺ T cells was measured by flow cytometry. (E) After treatment with different doses of hUC-EVs-ATO (CD4⁺ T cells: hUC-EVs-ATO = 1:1, 1:5, 1:10) for 72 h, the frequencies of IFN-γ⁺CD4⁺, IL-17⁺CD4⁺ and Tregs were measured via flow cytometry. The data are representative of three independent experiments. Data are shown as the mean ± SEM. *P < 0.05; **P < 0.01; ***P < 0.001, n.s. = not significant