Fig. 8. Immunohistochemical analyses showing a drastic reduction of positive signals for VCAM1 (B,G,H), but not PECAM1 (A,E,F) and TIE2 (C,D,I,J), in vascular endothelial cells of the affected livers (A-D) and kidneys (E-J) in the P7 Sox17^+/--Sox18^-/- neonates. Anti-PECAM1 staining shows sparse and dilated liver sinusoids (right in A) and irregular kidney vasa recta (right in E) in the severe Sox17^+/--Sox18^-/- group. Anti-VCAM1 staining reveals that its signal intensities are clearly reduced in the sinusoids and central veins of the livers (B) and in the vasa recta of the kidney outer medulla (arrows in G,H) of the affected Sox17^+/--Sox18^-/- pups. Its positive signals were found in the glomerular afferent and efferent arterioles (arrowheads) and some microvasculatures located in their cortex interstitium (G). Anti-TIE-2 staining shows no difference in their immunoreactivity in the liver sinusoids (C, arrows in D) and the kidney outer medulla vasa recta (arrows in I,J) between the severe Sox17^+/--Sox18^-/- and Sox18^-/- groups. (D) Higher magnification of TIE2-positive sinusoids (broken line). (F,H,J) Higher magnification of the outer medulla vasa recta shown in E,G and I, respectively. Asterisks indicate non-specific staining in apical surface of the hepatic capsule (A-C) and in lumen of the renal tubular epithelia (G). ct, cortex; gl, glomerulus; im, inner medulla; om, outer medulla. Bar, 50 µm.