DAF^−/−/Crry^−/−/C3^−/− platelets are more sensitive to alternative pathway complement attack than DAF^−/−/Crry^−/−/C3^−/− erythrocytes. FACS analysis of C3 deposition on DAF^−/−/Crry^−/−/C3^−/− platelets and erythrocytes after 20 minutes (A-C) or 60 minutes (D-F) of incubation with various concentrations of wild-type mouse plasma in 10 mM EGTA-MgCl₂. MFI indicates mean fluorescence intensity. Bars in panels C and F represent means (± SEM) of triplicate assays.