Analysis of immune response-associated soluble factors expression in fetal brain homogenates after maternal innate immune activation. Pregnant mice received a single i.p. injection of poly(I:C) or PBS on GD16 and were killed 6 h and 24 h after treatment. IRSF concentrations in fetal brain homogenates were determined by multiplexed bead-based immunoassay (Milliplex Map). Only factors detected at least at one time-point are plotted. (A) Comparison of the expression levels of pro- and anti-inflammatory cytokines between saline and poly(I:C) injected animals. IL-1α, IL-2, IL-3, IL-4, IL-5, IL-6, IL-12(p40), IL-12(p70), IFN-γ, TNF-α and LIF were not detected at both time-points. At 6 h after treatment, IL-7 and IL-13 showed significantly higher concentrations as compared to PBS-treated animals. At 24 h post-treatment, only IL-1β showed significantly higher expression levels compared to saline-treated animals. Circadian variations in control animals in the concentration levels of IL-1β and IL-9 were also detected. (B) Comparison of chemokine expression levels showed increased concentration levels of IP-10 and MIG 6 h after treatment while MCP-1, IP-10 and MIP-1α were increased at 24 h post-treatment. Significant changes in control animals between the two times of the day were observed for eotaxin, MCP-1, MIP-1α and MIG. LIX and MIP-2 were not detected. (C) Analysis of changes in CSF expression levels showed that only VEGF was significantly up-regulated 6 h after poly(I:C) treatment. VEGF expression was also significantly different between the 4 p.m. and 10 a.m. time-points. G-CSF was below detection limits. The numbers of animals analyzed were as follows: PBS 6 h, n = 10; poly(I:C) 6 h, n = 10; PBS 24 h, n = 10; and poly(I:C) 24 h, n = 9. Values are presented as the mean ± standard error of the mean. Results obtained in pg/mL were normalized to pg/100 μg of total protein. *P <0.05 between PBS and poly(I:C) groups at 6 h and 24 h post-injection. +
P <0.05 between 6 h and 24 h after PBS injection. Statistical significance was based on Student’s t-test comparisons between groups. ND: not detected.