Figure 2

CXCL13 is predominantly expressed in the cortical endothelium after stroke. Representative confocal images of cortical CXCL13 protein (red; 594 nm) colocalized with (A) endothelial cells (CD31; green; 488 nm), (B) astrocytes (GFAP; green) and (C) neurons (NeuN; green) 24 hours following stroke at time of peak protein expression. DAPI (blue; 405 nm) was used as a nuclear counterstain and shown in the merge panel. Note the predominately vascular expression of CXCL13 at the blood–brain barrier in both control mice (top row of each pair) and repetitive hypoxic preconditioning (RHP)-treated mice (bottom row of each pair). Scale bar = 20 μm; n = 3/group; duplicate staining. Zoomed images from adjacent sections show distinct colocalization with (D) CD31 and (E) CXCL13 expression within GFAP + astrocyte endfeet. (F) Zoomed image of the corpus callosum (pale band within NeuN + staining) shows neurons with punctuate CXCL13 staining denoted by white asterisks. Scale bar for zoomed images = 30 μm. Images were captured using a Leica TCS SP5 confocal microscope with automated DIC optics, a 63× oil objective and LAS AF software, at 21 °C. Final figures were created using Adobe Photoshop without gamma adjustments. tMCAo, transient middle cerebral artery occlusion.