(A, B) Immunofluorescence analysis of the old APPPS1 slice in co-culture (14 DIV) using antibodies 6E10 (green) and CD68 (red). Nuclei were counterstained using DAPI (blue). Image of boxed region in A is depicted at higher magnification in B and reveals clustering of several CD68 positive cells around amyloid plaques. Scale bars: 100 µm (A) and 10 µm (B).(C) Quantitative analysis of plaque-associated CD68 positive cells in co-culture samples at 7 and 14 DIV reveals a trend towards increased number of CD68 positive cells. The values represent mean ± SEM from at least 3 independent experiments, including total of at least 6 independent slice culture dishes (n.s.= not significant).(D) Quantitative analysis of co-culture samples at 7 and 14 DIV reveals a decrease in plaque size. The values represent mean ± SEM from at least 3 independent experiments, including total of at least 6 replicates (***P < 0.001).(E) Quantitative analysis of plaques surrounded by CD68 positive cells (clustered plaques) in co-culture samples at 7 and 14 DIV reveals an increase in the number of clustered plaques. The values are expressed as percentages of clustered plaques from the total number of amyloid plaques. The values represent mean ± SEM from at least 3 independent experiments, including total of at least 6 independent slice culture dishes (***P < 0.001). 