(D-F) Immunofluorescence analysis of young WT and old APPPS1 slices cultured alone or in co-culture at 7 DIV and immunostained using neuronal (NeuN), astrocytic (GFAP) and microglial (CD68) markers (green) reveals reduced NeuN and GFAP and increased CD68 immunosignal. Scale bar: 75 µm 