Half-life of injected platelets and serum TPO levels. (A) The percentage remaining of injected CFDA SE–labeled platelets at each time from either hPF4×6+ (●) or WT () mice injected into animals of the same background as measured by flow cytometry is shown. Means values ± 1 SD are shown. n = 3 per arm. (B) Serum PF4 levels in hPF4×6+ animals and WT littermates. n indicates the number of specimens. Data shown as average + 1 SD. Each specimen was analyzed in duplicate.