RIPK1 and Stroke: Ripk1 and Casp8 expression in the ipsilateral hemisphere followed the same pattern: they were significantly up-regulated by stroke (P < 0.01 for Ripk1 and P < 0.001 for Casp8) and reduced by NSC transplantation and the injection of proliferation-supporting medium to levels similar to healthy mice (Figure 2A-E).