Cells expressing L-plastin are more abundant across the heterozygous mutant (psen1K97fs/+) zebrafish brain than in wild type siblings at 24 months.
Immunostaining for the pan-leukocyte marker L-plastin supports increased numbers of microglia in the forebrain (A-B), midbrain (C-D) and hindbrain (E-F). Increased microglial abundance is evident in psen1K97fs/+ heterozygotes in both ventricular (D.i, F.i) and parenchymal (D.ii) regions compared to wild types (C, E). (G) Significant differences in MFI were observed between the forebrain, midbrain and hindbrain of psen1K97fs/+ and psen1+/+ fish; **p = 0.0048, ***p = 0.0005, ****p < 0.0001; two-way ANOVA with Sidak’s multiple comparisons test. Data presented as means with SEM. Scale bar 50 μm in all images.