Fig. 8

Effect of i.c.v. injection of anti-proBDNF antibody on fear memory and meningeal immune activity in the septic mice. Mice were bilateral i.c.v. injected with 1 μg McAb-proB 3 days before LPS injection. Behavior tests were performed 1 day after LPS injection. a Representative images showed the broad and thorough diffusion of drugs in cerebroventricular lumen following i.c.v. injection with methylene blue. b McAb-proB i.c.v. injection did not influence weight of mice. c–e There was no difference of c fear conditioning acquiring performance in each group, nor McAb-proB increased the freezing time of d contextual or e cued fear conditioning test as compared to IgG control after LPS injection. n = 6 in each group. Data b, c, and e were analyzed by repeated measures ANOVA and followed by Bonferroni post hoc test and data d was analyzed by one-way ANOVA and followed by Tukey post hoc test, *P < 0.05, **P < 0.01. f–p Meninges were harvested 5 days after LPS injection for flow cytometry analysis and qPCR. f–j Flow cytometry indicated that McAb-proB i.c.v. injection did not alter immune cell subpopulation, except for the greater percentage of j CD11b⁺ monocytes/macrophages in CD45⁺ cells in the meninges, as compared to IgG control. n = 4 in each group. k–p No difference in CD4 gene level or gene expression of IL-1β, IL-6, IL-4, IFN-γ, and IL-13 in the meninges between McAb-proB-injected mice and isotype-injected control after LPS injection. n = 5 in each group. Experiments were performed at least in triplicate. Data f–p were analyzed by unpaired T test, *P < 0.05, **P < 0.01. Data are presented as mean ± SEM. Con = saline injected control, McAb-proB = monoclonal anti-proBDNF antibody injection, IgG = isotype Igg injected control, i.c.v. = intracerebroventricular