APP and Alzheimer disease: Nonetheless, the measurements of OPC process domains, together with Neurolucida and Sholl analyses, all indicate that OPC shrinkage is a key feature in APP/PS1 at 14 months and is associated with increased process branching, giving OPCs a more fibrous appearance that is similar to “reactive” NG2 cells reported in human AD and AD models (Li et al., 2013; Nielsen et al., 2013; Vanzulli et al., 2020), as well as injury models (Ong and Levine, 1999; Butt et al., 2005; Jin et al., 2018), and this was not observed in age-matched controls.