HTRA1 and leukodystrophy: By contrast, no differential expression of any adult-onset leukodystrophy gene was observed in the E15 hippocampi and primary cortical neurons after OGD experiments between APPPS1 and WT strains, likely given the fact that these genes, although expressed in neurons, mainly exert a critical role on microglia (TREX1 and CSF1R), astrocytes (NOTCH3 and HTRA1), and endothelial cells (NOTCH3, HTRA1, TREX1, EIF2B2, EIF2B3, and EIF2B5) (http://web.stanford.edu/group/barres_lab/brain_rnaseq.html) that are minimally present in E15 hippocampi and primary cortical neuronal cultures.