The protective nature of Aβ is also evident in vivo as 5XFAD mice [genetic AD mouse model harboring the 5 most prominent familial AD mutations (Oblak et al., 2021)] have significantly better survival profiles than wild type mice in a model of Salmonella typhirium-induced meningitis, and as APP knockout mice fare worse than do wildtypes (Kumar et al., 2016). Here, APP is linked to Alzheimer disease.