Protection by cαStx2 in mice injected with Stx2a. Male (A) or female (B) mice were given 3 ng Stx2a intraperitoneally, and then, 1 h later, buffer or cαStx2 was administered intravenously at the doses listed in mg/kg. n = 5 mice/group. For panel A, P ≤ 0.016 for the survival curve from all groups compared to the survival curve for the control. For panel B, P ≤ 0.008 for the 3 and 5 mg/kg survival curves compared to the survival curve for the control.