Effect of PKK and fXII ASOs on PKK and fXII activation in vivo. Pooled plasma samples from PKK, fXII or Control (Ctrl) ASO treated male C57BL/6 mice (3 weeks at 80 mg/kg/wk dose, n = 8 per treatment group) were subjected to 2-color immunoblot analysis of PKK (A, bottom row, shown in red) and fXII (A, top row, shown in red) complexes with α2-antiplasmin (A2AP, shown in green). PKK (A, bottom row) and fXII (A, top row) proteins are marked by asterisks. Complexes of PKK (A, bottom row) or fXII (A, top row) with A2AP are stained by both antibodies and are marked by arrows. Pooled plasma samples from PKK or fXII ASO treated male C57BL/6 mice (3 weeks at indicated dose, n = 8 per treatment group) were subjected to immunoblot analysis of kallikrein heavy chain levels (D). fXIIa complexes with antithrombin (AT) were analyzed in plasma samples from PKK and fXII ASO treated male C57BL/6 mice (3 weeks at indicated dose, n = 8 per treatment group) by ELISA (B). Mean values of fXIIa-AT complex levels and fXII plasma protein levels were plotted against PKK protein inhibition for the direct comparison (C). *P ≤ .05, **P ≤ .01 and ***P ≤ .001 compared with untreated control.