Comparative Factor Ⅻ Contact Activation at Hydrophilic and Hydrophobic Surfaces and Interactions with Prekallikrein and Factor Ⅺ

摘要

Blood coagulation resulting from contact activation due to blood - material interactions remains a challenge in the use of blood-contacting devices. The initiating step of the intrinsic pathway of plasma coagulation cascade is widely accepted to be surface contact activation of the blood zymogen FⅫ (Hageman Factor) into an active-enzyme form (FⅫa). This activation facilitates the assembly of a contact activation complex that is essential for enzyme amplification via reciprocal-activation prekallkrein (PK) and then FⅫ, as well as cascade propagation by FⅫa-mediated factor Ⅺ hydrolysis. This study seeks to clarify the differences between active FⅫ arising from interactions with hydrophilic vs. hydrophobic surfaces, and subsequent interactions of activated FⅫ with PK and coagulation factor FⅪ.