Platelet signaling mutants differentially impact the hemostatic plug core and shell. (A) Platelet accumulation (CD41) and P-selectin expression over time following laser injury in wild-type (WT, gray lines) and semaphorin 4D-deficient (Sema4D, black lines) mice. Values are mean area ± SEM for n = 33 injuries in 5 WT mice and n = 44 injuries in 7 Sema4D mice. (B) A comparison of shell and core area 2 minutes post-injury. Data are normalized to mean area of the wild-type for each region and are expressed as mean ± SEM. Statistical analysis was performed by 2-way ANOVA with Bonferroni post-hoc test. The 95% confidence intervals for the difference between means (µ_WT − µ_Sema4D) are −0.6494 to 0.2299 and −0.9920 to −0.1127 for the shell and core, respectively. (C) Platelet accumulation (CD41) and P-selectin expression following laser injury in cremaster muscle arterioles of wild-type (WT, gray lines) and G_i2α(G184S) mice (black lines). Values are mean area ± SEM for n = 47 injuries in 6 WT mice and n = 48 injuries in 5 G_i2α(G184S) mice. (D) A comparison of shell and core area 2 minutes post-injury as in B.