SPP1 and Stroke: Interestingly, 15 and 24 h post-tMCAO a significant increase of osteopontin and CD44 receptor expression was observed in peri-infarct NVU cells, with the strongest increase 15 h post-stroke onset and most prominent in endothelial cells and pericytes (Fig. 1a,b,e,f and Supplementary Fig. S2).