Figure 5.
Activated ILC2 improve cognitive function in aged mice. (A) ILC2 were isolated from brains of aged mice and cultured in vitro with IL-33, IL-2, IL-7, and SCF for 4 wk. The Object Placement Test was performed with aged mice that received i.c.v. injection of 2 × 105 in vitro expanded and activated brain ILC2 or PBS. Mice were rested for 1 wk after surgery before behavior testing. Distance traveled in the Open Field Test was quantified. Data are from 8–11 mice per group, pooled from two independent experiments. (B) Percentage of time spent with familiar or displaced objects in the Object Placement Test. Data are from 8–11 mice per group, pooled from two independent experiments. (C) The Morris Water Maze was performed with mice that were i.c.v. injected with in vitro expanded and activated brain ILC2 or PBS. Percentage of time spent in the target quadrant and the number of entries to the target zone were quantified. Data are from 9–11 mice per group, pooled from two independent experiments. (D) RNA-Seq was performed with sorted microglia, ILC2, or T cells from the brains of aged mice treated with IL-33 daily for 7 d. Principal component analysis was performed. (E) MA (log-ratio versus mean log-expression) plots comparing the gene expression profiles. (F) Venn diagrams depicting the numbers of differentially expressed genes. (G) Pathway analysis of differentially expressed genes. (H) Pathway analysis of genes that are highly expressed in brain ILC2 but not in microglia or brain T cells of IL-33–treated aged mice. (I) List of effector molecules, receptors, and transcription factors that are highly expressed in brain ILC2 of IL-33–treated aged mice. (J) Heatmap depicts the expression of effector molecules expressed by different immune cell subsets in the brains of IL-33–treated aged mice. (K) Representative flow cytometry profiles of IL-5 and IL-13 expression by brain T cells or ILC2 in PBS- or IL-33–treated aged mice. (L) Quantification of the number of IL-5– or IL-13–producing brain T cells and ILC2 in IL-33–treated aged mice. Data are from three mice per group and are representative of two independent experiments. Error bars are mean ± SEM. *, P < 0.05; **, P < 0.01. n.s., not significant.