Peptide Inhibitor of Complement C1 Inhibits the Peroxidase Activity of Hemoglobin and Myoglobin

Figure 1

PIC1 inhibits peroxidase activity of Hb in RBC lysates. (a) RBC lysates (1.25 × 10⁸ cells/ml equivalents (eq)) from four donors were incubated with increasing concentrations of PIC1. After a 5-minute incubation, samples were combined with TMB for 15 seconds and absorbance was read at 450 nm. Data are means of three independent experiments ± SEM. (b) Dose-response inhibition of RBC lysates from one donor at various concentrations by PIC1. Data are means of four independent experiments ± SEM. (c) Increasing amounts of human AB RBCs were added to human O serum and cells allowed to lyse. PIC1 was then added to the serum aliquots and after a 5-minute incubation, samples were combined with TMB for 15 seconds and absorbance was read at 412 nm. Data are means of three independent experiments ± SEM.

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