Astrocyte activation following Aβ infusion. WT and IL1raKO mice were infused with Aβ or vehicle, and brains prepared as in Figure 2. A) Levels of the pro-inflammatory astrocyte-derived cytokine S100B showed a similar degree of upregulation in Aβ-infused IL1raKO and WT mice. B) Numbers of GFAP-positive astrocytes were increased to a similar degree in both WT and IL1raKO mice infused with Aβ. (error bars = SEM; p > 0.05 between Aβ-infused IL1raKO and WT mice).