Complement-injured MSCs are less potent in suppressing T-cell responses. MSCs (2 × 10⁶) were incubated at 37°C with or without 30 μL of NHS in 100 μL of GVB⁺⁺ buffer for 30 minutes. After this, washed MSCs were mixed with CFSE-labeled, and activated human T cells at different ratios. For human T-cell activation, 1 × 10⁶ of PBMCs were incubated with anti-CD3/CD28 Dynabeads following manufacturer provided protocols. After 4 days of incubation at 37°C, the efficacy of MSCs in inhibiting activated T-cell proliferation was assessed by measuring CFSE dilution on CD4⁺ T cells using flow cytometry. Representative results of 3 individual experiments. Data are mean ± SD