Figure 6
The density of microglia was increased in the Xpnpep1−/− CA3 area. (a) Representative images of hippocampal CA3 regions stained with CD68 and Iba1 antibodies showing a higher number of microglia in Xpnpep1−/− (bottom) than WT (top) mice. Scale bars, 50 µm. (b) Higher magnification views of areas indicated by the dotted white box in panel (a) show morphological features of normal resting microglia in both Xpnpep1+/+ (top) and Xpnpep1−/− (bottom) mice. Scale bars, 10 µm. Note the punctate immunoreactive signals of CD68 (arrows) near the cell body but not the processes of microglia. (c) Increased density of microglia in the Xpnpep1−/− CA3 region. n = 6 slices from 3 mice per genotype. U = 82 (Iba1+) and 102.5 (Iba1+CD68+), Z = − 4.39 (Iba1+) and − 3.97 (Iba1+CD68+), ***p < 0.001 by Mann–Whitney test. (d) Microglia in the hippocampal CA1 area were immunostained with Iba1 antibodies (left) and merged (right) with DAPI signals. Scale bars, 50 µm. (e) Quantification of Iba1-positive cell density in hippocampal CA1 subfields. n.s., not significant. t(10) = − 0.17, p = 0.87 by Student’s t-test. (f) Iba1-immnostained (left) and merged (right) images with DAPI staining showing normal density of microglia in the Xpnpep1−/− (bottom) DG subfield. Scale bars, 50 µm. (g) The density of microglia in the hippocampal DG is not changed by aminopeptidase P1 deficiency. n.s., not significant. t(10) = 1.59, p = 0.13 by Student’s t-test. (h,i) Western blot images (h) and quantification (i) of Iba1 and CD68 proteins in the hippocampal lysates. n = 4 pairs. α-tubulin was used as a loading control for western blotting. t(6) = − 0.21 (Iba1) and − 0.81 (CD68), p = 0.84 (Iba1) and 0.45 (CD68) by Student’s t-test. n.s., not significant.
