Adhesion of platelets to immobilized FKN under physiologic flow conditions. (A) Adhesion of platelets after 2 minutes at the indicated shear rate to immobilized FKN (closed bars). Control surfaces (open bars) were prepared in the same way with the omission of FKN to determine nonspecific background binding. (B) Adhesion of platelets to FKN coimmobilized with VWF (closed bars) or to VWF solely treated surfaces (open bars). Conditions were identical to panel A, except that VWF was present. The rate of nonspecific background adhesion to the control surface was subtracted from the presented adhesion rates. Results are the mean ± SEM of at least 4 independent experiments with blood from different donors. **P < .01 in 1-way analysis of variance with Bonferroni Multiple Comparison Test versus control or VWF adhesion rates. (C) Adhesion of platelets to VWF coimmobilized with FKN at the indicated doses as a function of time. The rate of nonspecific background adhesion to the control surface was subtracted from the adhesion rates. Results are the mean ± SEM of a representative experiment performed 3 times. Adhesion rates for .5 μg and 1.5 μg were omitted for clarity.