Figure 7. The annexin A2 expression in vascular endothelial cells . At P15, mice reared in room air (A, E, C) or mice with hypoxia-induced retinopathy (B, D, F) were killed (n=6), and ocular frozen sections were stained with a rat antibody directed against CD31 or a rabbit anti-murine annexin A2 antibody (B, D, F). Secondary antibodies were a goat anti-rabbit IgG conjugated with FITC and a Cy3-conjugated donkey anti-rat antibody. Small cross-sections of retinal vessels are evident in the CD31-stained retina (red) from a normal mouse, while dilated vessels and new vessels can be seen in the CD31-stained retina from a mouse with ischemic retinopathy. There is no detectable staining for annexin A2 in the retina of the mouse reared in room air, but there is prominent staining in the retina of the mouse with ischemic retinopathy (green). Merging of the images for the retina of the mouse with ischemic retinopathy (bottom, right) by simultaneously viewing with the red and green channels, demonstrates colocalization of CD31 and annexin A2, indicating that annexin A2 is expressed in vascular endothelial cells. Scale bar represents 100 μm.