Characterization of hGPVI-Fc. (A) Three micrograms purified hGPVI-Fc was subjected to SDS-PAGE under nonreducing (NR) and reducing (R) conditions, and the gel was stained with Coomassie brilliant blue. (B) One microgram purified hGPVI-Fc was subjected to SDS-PAGE under reducing conditions and was immunoblotted with HRP-conjugated antihuman Fc antibodies or JAQ1. (C) Dose-dependent binding of hGPVI-Fc to immobilized collagen (50 μg/mL) and CRP (2 μg/mL) was measured by ELISA (mean ± SD of 3 individual experiments). (D) hGPVI-Fc partly inhibits collagen- and CRP-induced aggregation of human and mouse platelets. Under stirring conditions, human or mouse PRP stimulated with the indicated concentrations of collagen or CRP in the presence (+) or absence of 20 μg/mL GPVI-Fc. Light transmission was recorded on a Fibrintimer 4-channel aggregometer. Results shown are representative of 6 experiments.