Platelet functional analysis. (A) Platelet aggregation was measured by turbidimetry on PRP from a control subject and the patient. PRP was stimulated by 5 μM adenosine diphosphate (green) and 1 μg/mL collagen (red). (B) Thrombus formation on collagen under blood flow was analyzed using DiOC₆-labeled platelets in whole blood perfused at a shear rate of 500 second⁻¹ over a collagen-coated coverslip during 5 minutes. Thrombus formation was visualized in real-time using an inverted microscope (Leica DMIRB) using a lens at 100× and a 488 nm filter. Images were acquired using a DP30BW camera and CellP software (Olympus) and processed with Histolab software (Microvision). Areas covered by platelet thrombi were measured on 10 different, randomly chosen, microscopic fields. (C) Thrombin generation was triggered by the addition of tissue factor (1 pM) to PRP after incubation with 5 μg/mL collagen. Results are from 1 experiment performed in triplicate, representative of 2 independent experiments.