Human coagulation Factor alpha-XIIa
Human Factor alpha-XIIa is a serine protease responsible for the activation of Factor XI to XIa in the contact activation system. Human Factor XII and prekallikrein are thought to be involved in a reciprocal activation mechanism in which Factor XIIa activates prekallikrein to kallikrein, which in turn converts Factor XII to XIIa. Factor XIIa activates Factor XI to XIa thereby triggering the Contact Factor cascade. Human Factor alpha-XIIa is activated from homogeneous Human Factor XII by an autoactivation process with Dextran Sulfate followed by repurification to isolate Factor alpha-XIIa and Factor beta-XIIa (Cat # HFXIIAB). Complete activation is observed on SDS-PAGE. Factor XIIa is >95percent pure by SDS-PAGE and activity is determined via clotting assay. Prepared from plasma found negative by FDA accepted methods for Anti-HIV1/2, Anti-HTLV I & II, HBsAg, Anti-HCV, Syphilis, HBC Ab, HIV-1 p24 Ag or HIV-1 RNA, HCV RNA and HBV RNA. Donors are screened for CJD (Creutzfeldt-Jakob Disease).