Quantitative release of fibrinopeptides. Clotting was initiated with the addition of thrombin to normal neonatal and adult fibrinogen. (A) Fibrinopeptide A and B concentration was determined for each time point over 120 minutes and reported as the neonatal to adult fold change. Mean fold change ± standard deviation is shown. (B) Cumulative release of fibrinopeptides was determined for normal and desialylated fibrinogen during clotting and reported as the neonatal to adult fold change for each fibrinopeptide. (C) Fibrinopeptide A release over time in desialylated fibrinogen compared with normal fibrinogen. The neonatal:adult fold change is reported. (D) Fibrinopeptide B release over time in desialylated fibrinogen compared with normal fibrinogen. The neonatal:adult fold change is reported. N = 3 triplicate experiments per group. Mean ± standard deviation is shown. *P < .05, **P < .01, ***P < .001, ****P < .0001.