MSC expression of PSGL-1, SLeX, and IL-10 following mRNA transfection. (A) MSCs were transfected with either PSGL-1 (top) or FUT7 (bottom) and 24 hours later, flow cytometry analysis detected surface expression of PSGL-1 and SLeX, respectively. (B) After MSC transfection with PSGL-1 or FUT7, surface expression of PSGL-1 and SLeX, respectively, was confirmed for up to 7 days. Mean intensity of transfected cell population was normalized to respective isotype controls. Mean ± SD (n = 3). (C) Coexpression of PSGL-1 and SLeX from simultaneous transfection with PSGL-1 and FUT7 mRNA. (D) IL-10 secretion from native and IL-10 mRNA-transfected MSCs. Mean ± SD (n = 3). (E) IL-10 mRNA-transfected MSCs exhibit improved immunosuppressive effects in vitro. Resting human CD4⁺ T cells were cocultured with native or IL-10-transfected MSCs in the presence of CD3/CD28 Dynabeads, and CD4⁺ T cell proliferation was measured (7-AAD⁺/BrdU⁺ cells were defined as proliferating cells). *P < .05, 1-way ANOVA using Tukey’s HSD; error bars represent SD (n = 3).