Risperidone treatment significantly reduces microglial activation in the CNS of immunized mice during EAE.

Abstract

<p><b>a.</b> Iba-1 expression (deep pink) in the cerebellum was assessed by immunohistochemistry and counterstained with hematoxylin (light purple). Shown are representative sections from unimmunized and immunized, vehicle and risperidone-treated mice as well as the “Iba-1 score” and “disease score” at time of euthanasia. <b>b &amp; c.</b> Iba-1 expression in the cerebellum (<b>b</b>) and all brain and spinal cord regions (<b>c</b>) assessed (cerebellum, hippocampus, brain stem, olfactory bulb, and spinal cord). Shown are the means and SEM of individual mice from one of two experiments (n = 3 per unimmunized group; 4–5 per immunized group). **p&lt;0.01 and ***p&lt;0.001 by one-way ANOVA with Newman-Keul's multiple comparison test. <b>d &amp; e.</b> Risperidone reduces the level of F4/80 (<b>d</b>) and the number of F4/80+ foci (<b>e</b>) in the cerebellum of immunized mice compared to vehicle treatment. F4/80 expression in the cerebellum was assessed by immunohistochemistry and shown are the means and SEM of individual mice (3 section per mouse) from 3 per unimmunized group and 4–5 per immunized group. * p&lt;0.05, **p&lt;0.01, and ***p&lt;0.001 by one-way ANOVA with Newman-Keul's multiple comparison test. <b>f &amp; g.</b> Risperidone reduces the expression of I-A (<b>f</b>) and CD40 (<b>g</b>) on microglia and macrophages in the CNS. CD45+ cells were isolated from the spinal cords of risperidone- and vehicle-treated, unimmunized and immunized mice 15 days post-immunization and the expression of I-A (<b>f</b>) and CD40 (<b>g</b>; ΔMFI compared to isotype controls) expressed as % of vehicle-treated, immunized group. Shown are the means and SEM of individual mice from three experiments (n = 10–15 per group). **p&lt;0.01 and ***p&lt;0.001 by one-way ANOVA with Newman-Keul's multiple comparison test (microglia) or unpaired Student's t test (macrophages) compared to vehicle-treated, immunized group.</p