TACE^ΔZn/ΔZn platelets are protected from storage-induced shedding of GPIb-α and increased posttransfusion clearance. (A) Surface expression of GPIb-α was determined by flow cytometry on freshly isolated or 15-hour stored platelet-rich plasma (PRP) from TACE^+/+ and TACE^ΔZn/ΔZn mice. Results are mean ± SEM; n = 6. n.s. indicates not significant. (B) Platelets from stored PRP from TACE^+/+ and TACE^ΔZn/ΔZn mice were washed in Tyrode-N-2-hydroxyethylpiperazine-N′-2-ethanesulfonic acid buffer and labeled with CFSE. A total of 10⁸ platelets/10 g of body weight was infused intravenously into TACE^+/+ mice. Blood was drawn at the indicated time points, and platelets were immediately analyzed by flow cytometry. Results are mean percentage CFSE-labeled platelets ± SEM; n = 4. ***P < .001. *P < .05.