Fig. 2.

hPMSCs inhibit the expression of PD-1 and the apoptosis of CD4⁺IL-10⁺ T cells in vitro. a Gating strategy. Forward scatter (FSC) and side scatter (SSC) gating were used to discriminate viable cells from cell debris. In vitro, the CD4⁺IL-10⁺ T cells were defined as those positive for CD4 and IL-10, and PD-1⁺ cells were defined as those positive for PD-1. Furthermore, the apoptosis rate in PD-1⁺ and PD-1⁻ cells was determined. b, c Representative dot plots of CD4⁺IL-10⁺ T cells and the percentage of CD4⁺IL-10⁺ T cells and the statistical evaluation of the levels of PD-1 in CD4⁺IL-10⁺ T cells from different groups of CD4⁺IL-10⁺ T cells. d The statistical evaluation of the apoptosis in different groups of CD4⁺IL-10⁺ T cells. e Dot plots from a representative experiment showing the apoptosis rate of PD-1⁺ and PD-1⁻ cells and the correlation analysis of PD-1 expression and the apoptosis rate. The results were obtained from three independent experiments, *P < 0.05, **P < 0.01