LRRK2 KO prevents neurotoxicity and diminishes microglial activation after in vivo cortical Tat injection. A–G, IHC for MAP2 (red), Iba1 (green), and DAPI (blue) in saline control animals (A, 10×; D, 10×), Tat-treated WT mice (B, 10×; C, 60×), and Tat-treated KO mice (E, 10×; F, 60×). G, LRRK2 KO significantly increases MAP2 expression in Tat-treated animals. H–N, IHC for CD11b (red), TUJ1 (green), and DAPI (blue) in saline control animals (H, 10×; K, 10×), Tat-treated WT mice (I, 10×; J, 60×), and Tat-treated KO mice (L, 10×; M, 60×). N, LRRK2 KO significantly increases TUJ1 expression in Tat-treated animals (*p < 0.05, **p < 0.01, one-way ANOVA with Newman–Keuls post hoc test). Scale bars: A, B, D, E, H, I, K, L, 60 μm; C, F, J, M, 11 μm.