Fig. 4. Immunohistochemical assessment of glial markers and correlation analysis. (A) GFAP immunohistochemical assessment showed higher astrocytic activation upon hippocampal injury in 4KI mice, compared with 3KI mice on day 3 (p=0.042) and compared with KO mice on day 15 (p=0.048). (B) Iba-1+ and Iba-1+/CD45+ signals were significantly lower in 3KI mice than in wild-type mice upon cortical injury on day 3 (p=0.016 and p=0.011, respectively), and the Iba-1+ signal was higher in 4KI mice than in KO mice on day 15 (p=0.038). Iba-1, CD45, and Iba-1/CD45 immunoreactivities in the hippocampus were all higher in 4KI mice than in 3KI mice on day 3 (p=0.009, p=0.019, and p=0.009, respectively). These markers further elevated on day 15, although the group differences disappeared. (C) A significant inverse correlation between injury volume reduction on MRI and Iba-1 immunoreactivity (r=-0.434, p=0.049), and a tendency for inverse correlation between MRI marker and Iba-1+/CD45+ (r=-0.430, p=0.052), were identified in correlation analysis. The asterisks (*) in figures indicate the side of injury core. The dotted lines show the border of injury core. Bar graphs show mean±standard errors of the mean. Scale bar, 100 μm. *p<0.05 and **p<0.01, significant on one-way analysis of variance with post hoc Tukey’s test (A, B) and Pearson’s correlation analysis (C). γ, correlation coefficients; 3KI, apoE3 knock-in; 4KI, apoE4 knock-in; GFAP, glial fibrillary acidic protein; KO, knockout; wt, wild-type.
© Exp Neurobiol
