Cross-linking of α
AP and α
AP(13-42)-HSA by fXIIIa to fibrinogen. FXIII was pre-activated to fXIIIa by thrombin, the thrombin inactivated with FPRck, and the fXIIIa then combined with fibrinogen and α2AP or α2AP(13-42)-HSA or α2AP(13-73)-HSA in transglutamination reactions. Reactions were terminated with SDS, DTT, and urea as described in "Methods". (A) depicts a Coomassie Blue-stained SDS-polyacrylamide gel highlighting the cross-linking of fibrinogen into γ-γ dimers (γ-γ) and α-polymers (α). (B) shows an anti-α2AP immunoblot of transglutamination reactions containing α2AP for the times identified above the lanes; the first lane contains α2AP alone. (C), right panel, is identical to B except that α2AP(13-42)-HSA was substituted for α2AP; (C), left panel, is identical to the right panel except an anti-HSA antibody was used. (D) is identical to (C), left panel, except that α2AP(13-73)-HSA was substituted for α2AP(13-42)-HSA. The position of molecular mass markers, is shown to the left or right of the panels.