Table 3.

ADP-stimulated binding of fibrinogen and VWF to human, murine, and mmHH platelets and inhibition by RGDS and tirofiban

	Human platelets	Murine platelets	mmHH platelets*
Ligand binding (Kd, nM)
Fibrinogen	66.5 ± 3.2	67.1 ± 2.8	ND
VWF	20.6 ± 2.8	25.6 ± 3.1	ND
IC50 for fibrinogen binding
RGDS, μM	3.5 ± 1.6	35.9 ± 7.1	2.3 ± 0.2
Tirofiban, nM	0.9 ± 0.2	1.6 ± 0.9	1.3 ± 0.3
IC50 for VWF binding
RGDS, μM	21.0 ± 1.2	68.6 ± 20.8	14.4 ± 10.3
Tirofiban, nM	1.2 ± 0.4	2.0 ± 1.0	1.5 ± 0.2

Values are the mean and 1 SE of 3 experiments.

ND indicates not done.

^*Transgenic mice are homozygous for a disabled murine αIIb gene and express a human αIIb transgene at a level approaching that of human platelets.²⁷