Histological analysis of brains of PbTg infected mice upon early depletion.

C57BL/6 mice were infected i.v. with 5*10⁴ PbTg-iRBC and then subdivided into groups that received either anti-Gr1, anti-Ly6G or anti-CCR2 mAb on d0 p.i. (early depletion). On day 6 p.i., tissue sections from the brain parenchyma of individual mice were assessed for pathological changes. (A) Standard H&E staining is depicted in the upper panels whereas immunohistochemical staining for anti-Mac3 and anti-CD3 are shown in the middle and lower panels, respectively. Representative sections from naïve mice are shown on the left whereas those from PbTg infected mice are displayed on the right. (B, C) Quantification of Mac3⁺ cells (B) and CD3⁺ cells T cells (C) in brain sections from the meninges and frontal cortex of individual mice. Scale bars indicate 100μm in the magnifications. Bars show mean ± SEM from n = 8 mice per group from 1 out of 3 independent depletion-infection experiments counted in 10 defined fields (High power fields, HPF) in the frontal cortex. Statistical analysis was performed using Kruskal-Wallis test and Dunn’s Post test and significant differences are indicated by the stars in brackets between the groups (* p<0.05).