Figure 1.

Inhibition of the AP by lufaxin in complementopathy models. (A) Inhibition of complement activation and cell killing of a PIGA-mutant TF-1 cell line by lufaxin (Luf) and anti-C5 mAb in the mHam test. Activation in healthy human serum (NHS) was potentiated by Shiga toxin (Stx; 10 μg/mL) or Sia (50 U/mL). Anti-C5 mAb (0.34 μM) and lufaxin (Luf; 2 μM) strongly inhibited the AP-specific Sia-induced activation (P < .01 [in comparison with Sia alone]) and inhibited Stx-induced activation less strongly. (B) In the mHam test, mAb and Luf significantly (P < .01 and .05, respectively) at concentrations of 2 and 0.34 μM, respectively, inhibited activation by serum from a patient with aHUS relative to aHUS serum without an inhibitor. (C) Lysis of erythrocytes from a healthy individual (red bars) and a patient with PNH (blue bars) in acidified NHS and inhibition by mAb and Luf. The sizes of the erythrocyte clones are type I, 65.1% and type III, 33.2%. At a concentration of 2 μM, Luf significantly inhibited lysis (P < .05).