Platelet thrombus formation, fibrin generation, and PDI secretion after laser-induced arteriolar wall injury in HPS6^−/− and WT mice. Platelet-specific anti-CD42b antibody and fibrin-specific mouse anti-human fibrin monoclonal antibody were infused into mice, and the cremaster arteriole subjected to laser injury and the induction of thrombus formation. (A) Representative images of the fluorescence associated with fibrin (green) and platelets (red) over 180 seconds after laser-induced vessel wall injury. (B) Median integrated platelet fluorescence intensity vs time in WT mice (dark red) and HPS6^−/− mice (red). (C) Median integrated fibrin fluorescence intensity vs time in WT mice (dark green) and HPS6^−/− mice (green). Data are from 30 thrombi in 3 mice for HPS6^−/− and WT mice. In panels A-C, platelet-specific anti-CD42b antibody and nonblocking polyclonal anti-PDI antibody were infused into mice to detect platelets and PDI during thrombus formation. (D) Representative images of fluorescence associated with PDI (green) and platelets (red) over 180 seconds of thrombus formation after laser-induced vessel wall injury in WT and HPS6^−/− mice. (E) Median integrated platelet fluorescence intensity during thrombus formation in WT mice (dark red) and HPS6^−/− mice (red). (F) Median integrated PDI fluorescence intensity during thrombus formation in WT mice (dark green) and HPS6^−/− mice (green). F, fluorescence intensity.