Figure 7: Anti-GPIbα platelet clearance in macrophage-depleted mice is via the AMR.

(a-e) Macrophages were depleted with clondrate liposomes via intravenous injection prior to study, and CFMDA-labelled antisera-opsonized platelets were injected with asialofeuin or fetuin and circulating platelets were quantified (a) as described in Fig. 6. n=5. ^{^^}P<0.01 versus fetuin-injected group at the same time point. *P<0.05, ^**P<0.01 versus baseline as determined by two-way analysis of variance followed by Bonferroni post hoc analysis. (b–d) Tissue sections of the spleen and liver harvested from normal or macrophage-depleted mice following the above circulation studies and were stained with anti-ASPGR1/2 (liver; red) (b,c) or anti-F4/80 (spleen; red) (d). Nuclei were counterstained with 4′,6-diamidino-2-phenylindole (blue). Arrows indicate co-localization of CFMDA-labelled platelets with ASPGR on hepatocytes. (e) Fluorescent platelet (green) localization was assessed with immunofluorescent microscopy at × 60 magnification and quantified with Image J. White scale bars, 10 μM. *P<0.05 as assessed by the Student’s t-test. Data are representative of five randomly selected fluorescent images.