Adhesion of platelets and GpVI ectodomains to modifications of peptides III-01 and III-30. (A) Static adhesion of human washed platelets to modifications of Toolkit peptides III-01 and III-30 and the effects of αIIbβ3 antagonist GR144053F (2 μM) and anti-GpVI antibody 10B12 (20 μg/mL). Data are the mean plus or minus SE (n = 6) of the absorbance measured at 405 nm. *Not significantly different from adhesion to GPP; †Significantly different from control within ligand group (P < .05). (B) Static adhesion of murine WT and FcRγ^−/− washed platelets to modifications of Toolkit peptides III-01 and III-30. Data are the mean plus or minus SE (n = 10) of the absorbance at 405 nm. WT platelets bound to the following peptides on 10 of 10 occasions: III-01a, III-01b, III-30, III-30b, CRP, and GFOGER. WT platelets bound to III-30a on 5 of 10 occasions. FcRγ^−/− platelets bound only to GFOGER on 10 of 10 occasions. (C) Adhesion of recombinant human and murine GpVI (D1D2-Cam) to modifications of Toolkit peptides III-01 and III-30. Data are the mean plus or minus SE (n = 6 for hD1D2 and n = 4 for mD1D2) of the absorbance at 450 nm. Note the y-axes are adjusted to show equivalence of binding of hD1D2 and mD1D2.