Fig. 4: Long- and short-term thrombocytopenia in mice and the effects on demyelination in the corpus callosum.

A Schematic illustration of the demyelination experiment, with a lysolecithin (LPC) injection performed in the corpus callosum (CC) at day 0. Wild-type (WT), Nbeal2-KO mice, or mice with depleted platelets were killed at different days post-lesion (dpl). Acute thrombocytopenia was induced in wild-type mice via two i.p. injections of the CD42b antibody at 3- and 5-dpl. These mice were killed at 7 dpl. B Graph showing the number of platelets in blood samples taken from mice before and after the injection (on days 0 and 2) of the anti-CD42b antibody. C High magnification images of the SEZ of an Nbeal2-KO mouse at 7 dpl, after immunostaining for laminin (in red, to mark blood vessels) and CD41 (in green, to mark platelets). The areas outlined in (C) are presented in (C1 & C2), showing CD41+ platelets within blood vessels. D Graph showing the mean % of the length of blood vessels (immunopositive for laminin) covered by CD41+ immunopositive platelets, in the brain hemispheres ipsilateral (ipsi) and contralateral (contra) of the demyelinating lesion (n = 3 per experimental group). E–H Microphotographs of the CC, in WT and Nbeal2-KO mice, at the site of demyelination, at 7- and 14-dpl, after immunostaining for PLP. The area of lesion was determined based on cell density and is outlined with the white, dotted line. I–L Higher magnification microphotographs of the CC, in WT, Nbeal2-KO mice and platelet-depleted mice, at the site of demyelination and at the contralateral site, at 7 dpl, after immunostaining for PLP. M Graph showing the density of PLP immunoreactivity at the area of lesion, as a percentage of the contralateral, un-lesioned, site at 7- and 14-dpl (n = 4 per experimental group). [scale bars: 100 μm in (C & E–H); 10 μm in (C’); 50 μm in (I). In the graphs, bars show mean values and error bars the SEMs. Statistical analysis was performed using 1-way ANOVA, followed by the Tukey post-hoc analysis, in (B), with the three starts indicating a p < 0.001 for 1, 2, and 4 days post-injection. 2-way ANOVA, followed by the Tukey post-hoc analysis, was performed in (D), and the statistical differences are shown with horizontal brackets and the respective post-hoc values. 3-way ANOVA, followed by the Tukey post-hoc analysis, was performed in (M). The overall p-value for the effect of demyelination (versus the control hemisphere) is shown. No overall effect was found for experimental group (not shown), or for time-point (n.s. not significant). LV Lateral Ventricle].