Fig. 4
From: Microglia limit the expansion of β-amyloid plaques in a mouse model of Alzheimer’s disease
Absence of microglia induces increase of Congo Red-labeled Aβ fluorescence surrounding plaques. a. An example of an Aβ plaque in APP/PS1/CX 3 CR1-iDTR mice at D13, D20 and D27, with blue curves indicating plaque border. A radial line from the center point towards the outer area of a plaque is separated by the plaque border, with the inside part representing area in the plaque (“in”, black) and the outside part representing the area surrounding the plaque (“out”, white). Scale bar, 5 μm. b. Fluorescence intensity across the line in a, with 5 μm inside the plaque and 5 μm outside the plaque. Shadow area represents fluorescence intensity surrounding plaques. c. Normalized fluorescence intensity surrounding plaques from D13 to D20. Microglia depletion in APP/PS1/CX 3 CR1-iDTR mice induced a significant increase of fluorescence in the area surrounding plaque (n = 30 plaques, ***P < 0.001, Wilcoxon matched-pairs signed rank test). d. In the second week after DT administration (from D20 to D27), fluorescence surrounding plaques showed no additional increase in APP/PS1/CX 3 CR1-iDTR mice (n = 30 plaques, P = 0.84, Wilcoxon matched-pairs signed rank test)