Adult SC expresses a panel of vascular markers.

<p>(A) Marker expression as determined by GFP expression (green, transgenic mice; see Methods) or immunostaining (red). Z-projections of limbal confocal planes encompassing SC. X and Y coordinate markers are slightly offset to indicate the curvature of SC. (B and C) Morphologically distinct cells comprise inner (IW) and outer walls (OW) of SC. (B) <i>Tie2-GFP⁺</i> SC immunostained with VECAD. Yellow lines indicate the locations of the XZ planes in bottom panels. Although <i>Tie2-GFP</i> continuously marks both walls, the cell junction marker VECAD is densely packed in IW but more widely spaced in the OW (bottom panels in B). This is consistent with IW cells being long (along Y axis) and thin (X axis) and OW cells being shorter and wider. The long thin nature of IW cells is clearly evident in the <i>Tie2-GFP</i> XY image (arrows). Confirming the identity of SC and its walls, fluorescent dextran that was perfused into the anterior chamber (yellow) accumulated at the IW (right panels). (C) Higher magnification images specifically showing IW and OW confirm this morphology. Z stacks encompassing either the IW SCE (Left) or OW SCE (Right) immunostained with VECAD were Z-projected in blend mode of Imaris to provide depth perception. Scale bar, (A) 100 µm and (B–C) 20 µm.