Figure 1: One ml samples of human blood were incubated with increasing amounts of IdeS for three hours at 37°C. Blood cells were spun down and the resulting supernatants were subjected to SDSPAGE under reducing conditions. At 10 μg IdeS/ml blood (lane 5 from the left) the heavy chain of IgG is completely degraded. The 31 kDa fragment of the heavy chain (IgG Heavy chain cleavage product) is clearly visible already at 1 μg IdeS.