Evidence that Hpr does not synergize apoL-I activity. The time periods required for full lysis of ETat 1.2S parasites were plotted against those required for commitment to lysis by various dilutions of different sera [from left to right: 3.3, 10, 20, 50, 66, and 100 × dilution of NHS; 2.2, 3.3, and 6.7 × dilution of Hp(r)−/−HS; 1 and 1.3 × dilution of FCS + apoL-I].