Fig. 5.
Effect of purified recombinant GPIbα fragments on platelet aggregation of the platelet-type vWD patient induced by low concentration of ristocetin. PRP (1.4 × 105 platelets/mL) of the patient with Met239 → Val substitution was mixed with purified recombinant GPIbα (WT and M239V) at a final concentration of 200 μg/mL. After 3 minutes of incubation, ristocetin (0.3 mg/mL) was added to PRP. Aggregation of the patient's platelets was measured as the increase in light transmittance as a function of time. Platelet aggregation was completely inhibited by purified M239V, whereas it was not by purified WT in the same condition.