C5AR2 and Alzheimer disease: The AD-selective genes in brain samples during the onset of AD in 3xTg-AD mice relative to age-matched wild-type animals primarily encompassed immunity as Rnase6 (Seto et al., 2022; Bolivar et al., 2024), Ms4a1 (Deming et al., 2019), Ccr1/6 (Halks-Miller et al., 2003; Subramanian et al., 2010; D'Angelo et al., 2020), Ifi204 (Green et al., 2022), Cxcl13 (Karaahmet et al., 2022), C5ar2 (Carvalho et al., 2022), Nlrc4 (Saadi et al., 2020), Serpina3n (Saroja et al., 2022), Il15 (Clark et al., 2021; Janelidze et al., 2018), and Osm (Yu et al., 2023; Whelan et al., 2019).