NAC, Mito-Tempo, and AQB-565-inhibitable ROS are responsible for oxidation and proteolysis of fibrinogen in IL-6–stimulated leukocytes. IL-6–stimulated RBC-lysed leukocytes from healthy donors (n = 6) were incubated with fibrinogen (4 mg/mL) and indicated various antioxidants and inhibitors as described in supplemental Methods; supplemental Figure 8B for indicated time periods. (A-H) Conditioned medium was analyzed by OxyBlot and immunoblotting using fibrinogen Aα-, Bβ-, and γ-specific antibodies. Data images are representative of 4 independent experiments.