Fig. 1. Blood replacement improves stroke outcomes.

a Experimental design. Mice (8~12 months old males) underwent tMCAO for 90 min. The occlusion and reperfusion were confirmed by a laser speckle imager (LSI). Mice were randomized into three groups: sham control, 250 µl, or 500 µl of blood from healthy donors (3~6 months old). Blood was transfused into stroke mice at 6.5~7 h post stroke. The same volume of blood was withdrawn from the recipient stroke mice during blood transfusion. Brain infarct volumes were measured at 23 h after ischemia induction. BBB permeability was evaluated at 1 h post blood replacement (BR). b BR reduced infarct volume in the cortex, striatum, and total hemisphere dose dependently. Sham control (circles, n = 6), 250 µl group (squares, n = 6), or 500 µl group (triangles, n = 6) of blood from healthy donors. c Representative triphenyltetrazolium chloride (TTC)-stained coronal brain sections used for infarction analyses. d Neurological deficits were significantly improved in the BR group. Sham control (circles, n = 8), 250 µl group (squares, n = 6), or 500 µl group (triangles, n = 6) of blood from healthy donors. e BR reduced Evans blue extravasation in the brain dose dependently. Sham control (circles, n = 6), 250 µl group (squares, n = 6), or 500 µl group (triangles, n = 6) of blood from healthy donors. f Representative coronal brain sections showing Evans blue extravasation. Data were presented as means ± SEM. One-way ANOVA followed by post hoc Fisher’s unprotected least-significant difference for multiple comparison tests. Source data are provided as a Source Data file.