Microglia were isolated as previously described [11 (link)]. Mice were anesthetized and hippocampi were dissociated from the brain and transferred to HBSS buffer. A neural dissociation kit (product No. 130-092-628, Miltenyi Biotec, Waltham, MA) was used to prepare a single-cell suspension, followed by a continuous 30% Percoll gradient at 700 g for 15 min. For microglia/macrophage isolation, cells were incubated with biotin-conjugated anti-CD11b antibody (eBioscience product no. 13-0112-82, Thermo Fisher Scientific, Waltham, MA), and CD11b + cells were isolated using Dynabeads Biotin Binder (Invitrogen product no. 11047, Thermo Fisher Scientific) and following manufacturer’s instruction.