Microglia activation is also present in various models of neurodegenerative diseases associated with abnormal protein aggregation such as in genetically modified mouse models mimicking Alzheimer’s disease amyloid pathology (APP23: Stalder et al., 1999; Bornemann et al., 2001; PS/APP: Matsuoka et al., 2001; PS1 + APP: Gordon et al., 2002; Tg2576: Frautschy et al., 1998; Benzing et al., 1999; Sasaki et al., 2002) or tau pathology (P301S tau: Bellucci et al., 2004; Yoshiyama et al., 2007; TgTauP301L: Sasaki et al., 2008; Thy-Tau22: Belarbi et al., 2011). The gene discussed is APP; the disease is early-onset autosomal dominant Alzheimer disease.