EndoS decreases the development of AIHA in BALB/c mice pretreated with 34-3C anti-RBC mAb. BALB/c mice were intravenously injected with 34-3C anti-RBC mAb; and 24 hours later, 20 μg of EndoS was intravenously injected. (A) Hematocrit values of individual mice treated with EndoS (○) or PBS (●) were measured 1, 2, 4, 6, and 8 days after injection of 200 μg 34-3C IgG2b mAb. Horizontal lines indicate mean values. (B). Representative histologic appearance of iron deposits in Kupffer cells from mice injected with 34-3C IgG2b anti-RBC mAb and then with EndoS. Note substantial reduction of iron deposits in livers from mice treated with EndoS, compared with completely untreated mice (original magnification ×200). (Top right panel) Higher magnification of iron deposits as indicated by arrows. (C) BALB/c mice were intravenously injected with 300 μg of 34-3C IgG1 or 200 μg of 34-3C IgG2a class-switch variant; and 24 hours later, 20 μg of EndoS was intravenously injected. Hematocrit values of individual mice treated with EndoS (○) or PBS (●) were measured 4 days after injection of 34-3C mAb. Horizontal lines indicate mean values. The normal range of hematocrit values (mean ± 3 SD) of 2- to 3-month-old BALB/c mice is represented as a shaded area.