Depletion (reduction) of serum IgGs moderately reduces MSC cytotoxicity. IgGs in NHS were depleted (reduced) using protein A beads. After this, MSCs were cultured with 10, 20, and 30 μL of NHS or IgG-depleted NHS in 100 μL of GVB⁺⁺ buffer. 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;