Antibody:	anti-Pecam (MEC 13.3)
Detection system:	Secondary antibody coupled to horseradish peroxidase

Structure	Cell Type	Level	Pattern	Image	Note
TS20: labyrinthine zone	endothelial cell	Present	Regionally restricted	1E WT PECAM1	Expression was detected in the normal tubular vessel structures in the vasculature of the labyrinth.

Structure	Cell Type	Level	Pattern	Image	Note
TS20: labyrinthine zone	endothelial cell	Present	Regionally restricted	1E Usp22-/- PECAM1	The immunolabeled endothelial cells did not form normal tubular vessel structures in the mutant.

Structure	Level	Pattern	Image	Note
TS18: extraembryonic blood vessel	Present	Regionally restricted	3D WT Pecam1

Structure	Level	Pattern	Image	Note
TS18: extraembryonic blood vessel	Present		3D Usp22-/- Pecam1	Fetal vessels that extend from the allantoic mesenchyme appeared to be disorganized.

Structure	Cell Type	Level	Pattern	Image	Note
TS15: chorioallantoic placenta	endothelial cell	Present		6B WT Pecam1

Structure	Cell Type	Level	Pattern	Image	Note
TS15: chorioallantoic placenta	endothelial cell	Present		6B Usp22-/- Pecam1	Staining suggests that the endothelial cells in Usp22 mutant placentas that originate from the allantois do not migrate into the chorionic epithelium as efficiently as the wild-type cells.