Fig. 1.

Screening of clinical serum and plasma samples for prolonged activity of classical convertases. Thirteen samples collected from the patients with C3 glomerulopathies were diluted to final concentration of 1 %, mixed with equal volume of NHS and inhibitor of C5 cleavage was added. Samples were incubated with sensitized sheep erythrocytes for indicated time period and then washed and incubated with guinea pig serum diluted in 40 mM EDTA-GVB buffer, which disabled de novo convertase formation but allowed development of lytic sites only from pre-existing convertases. Percentage of lysis measured at 405 nm was referred to the equal amount of sensitized erythrocytes lysed with equal volume of water. Data were collected from three independent experiments, statistical significance was assessed by two-way ANOVA at **p < 0.01 and ***p < 0.001, respectively. Only four clinical samples including #7 were shown for better clarity of the graph but none of the clinical samples but #7 showed statistically significant differences when compared to NHS controls. Graph showing all 13 patients versus healthy controls (normal human serum) is presented in Supplementary Fig. 1