Platelet count data are presented following MWReg30 doses of 0.05 mg/kg, 0.2 mg/kg, and 0.4 mg/kg, administered to C57BL/6 wild-type mice (WT), FcγRI/RIII(−/−) mice, and FcγRIIb(−/−) mice. Platelet counts were determined at several time points up to 3 days, and normalized by the baseline platelet counts. Symbols represent the mean % platelet counts, relative to pretreatment values, and error bars represent the standard deviation about the mean (n=5–7 mice per strain per dose). Relative to wild-type mice, FcγRI/RIII(−/−) mice demonstrated reduced sensitivity to MWReg30 and FcγRIIb(−/−) mice demonstrated increased sensitivity to MWReg30.