MSCs cytotoxicity is mediated through MAC. MSCs (5 × 105) were subjected to the same BCECF leakage-based cytotoxicity assays with 10, 20, and 30 μL of NHS, C9–depleted (A) or C5–depleted sera (B) in 100 μL of GVB++ buffer. After incubation at 37°C for 30 minutes, MSCs cytotoxicity was assessed by measuring BCECF leaked into the supernatants. Representative results of 3 individual experiments. Data are mean ± SD, *P < .05. (C) Blocking the assembly of MAC reduces MSC cytotoxicity after their contact with sera. MSCs (5 × 105) were cultured with 30 μL of NHS in 100 μL of GVB++ buffer. After the setup, the cells were divided into 2 groups. Ten, 20, or 40 μg/mL of goat anti-C5 IgG or control goat IgG were then added. After incubation at 37°C for 30 minutes, MSC cytotoxicity was assessed by measuring levels of BCECF leaked into the supernatants. Representative results of 3 individual experiments. Data are mean ± SD, *P < .05.
