Antibody:	anti-CD34
Detection system:	Secondary antibody coupled to fluorescein

Structure	Level	Pattern	Image	Note
TS14: vascular plexus	Present	Widespread	1A	Expressed in the capillary plexus distributed throughout the embryo.

Structure	Level	Pattern	Image	Note
TS15: intersomitic blood vessel	Present		1B
TS15: vascular plexus	Present	Regionally restricted	1B	Expressed in the intersomitic vessels and adjacent capillary plexus.

Structure	Level	Pattern	Image	Note
TS15: intersomitic blood vessel	Present		1C

Structure	Level	Pattern	Image	Note
TS21: hindlimb	Present	Regionally restricted	1D	Expressed in the vessels surrounding the developing bone.

Structure	Level	Pattern	Image	Note
TS21: spinal cord vascular element	Present	Regionally restricted	1E	Expressed in the vessels surrounding and within the neural tube.

Structure	Level	Pattern	Image	Note
TS12: blood vessel	Present	Regionally restricted	1F	Expressed in the vessels in head fold.
TS12: future brain neural fold	Present	Regionally restricted	1F	Expressed in the blood vessels in head fold.

Structure	Level	Pattern	Image	Note
TS11: yolk sac mesoderm	Present	Scattered	2A	Expressed in the mesodermal cells, which may correspond to the presumptive hemangioblastic progenitor cell type.

Structure	Level	Pattern	Image	Note
TS14: yolk sac blood vessel	Present	Widespread	2B	Expressed in the endothelium.
TS14: yolk sac	Present	Regionally restricted	2B	Expressed in the hematopoietic cells that exist either as single cells or as clusters of cells.

Structure	Level	Pattern	Image	Note
TS14: yolk sac blood vessel	Present	Widespread	2C	Expressed in the endothelium.
TS14: yolk sac	Present	Regionally restricted	2C	Expressed in the hematopoietic cells that exist either as single cells or as clusters of cells.

Structure	Level	Pattern	Image	Note
TS14: yolk sac blood vessel	Present	Widespread	2D	Expressed in the endothelium.
TS14: yolk sac	Present	Regionally restricted	2D	Expressed in the hematopoietic cells that exist either as single cells or as clusters of cells.

Structure	Level	Pattern	Image	Note
TS14: yolk sac blood vessel	Present	Widespread	2E	Expressed in the endothelium.
TS14: yolk sac	Present	Regionally restricted	2E	Expressed in the hematopoietic cells that exist either as single cells or as clusters of cells, which were in physical contact with the Cd34-positive endothelial cells.

Structure	Level	Pattern	Image	Note
TS14: yolk sac	Present	Regionally restricted	2F	Expressed in the hematopoietic cells that exist either as single cells or as clusters of cells.
TS14: yolk sac blood vessel	Present	Widespread	2F	Expressed in the endothelium.

Structure	Level	Pattern	Image	Note
TS21: liver	Present		3A	Expressed in the nonendothelial cells.
TS21: liver vasculature	Present		3A

Structure	Level	Pattern	Image	Note
TS21: liver	Present		3B	Expressed in the nonendothelial cells.
TS21: liver vasculature	Present		3B

Structure	Level	Pattern	Image	Note
TS21: thoracic segment of trunk	Present	Regionally restricted	3C	Expressed in the para-aortic region, nonendothelia and endothelia cells.

Structure	Level	Pattern	Image	Note
TS21: bone	Present	Regionally restricted	3D	Expressed in cells located in the region of the developing bone marrow, nonendothelia and endothelia cells.

Structure	Level	Pattern	Image	Note
TS14: vascular plexus	Present	Regionally restricted	4A	Expressed in the filopodial structures at the growing end of the developing cephalic capillary plexus.

Structure	Level	Pattern	Image	Note
TS14: vascular plexus	Present	Regionally restricted	4B	Expressed in the filopodial structures at the growing end of the developing cephalic capillary plexus.

Structure	Level	Pattern	Image	Note
TS14: vascular plexus	Present	Regionally restricted	4C	Expressed in the filopodial structures at the growing end of the developing cephalic capillary plexus.

Structure	Level	Pattern	Image	Note
TS14: vascular plexus	Present	Regionally restricted	4D	Expressed in the filopodial structures at the growing end of the developing cephalic capillary plexus.

Structure	Level	Pattern	Image	Note
TS14: intersomitic blood vessel	Present	Regionally restricted	4E	Expressed in the filopodial structures at the growing end.

Structure	Level	Pattern	Image	Note
TS14: vascular plexus	Present	Regionally restricted	4F	Expressed in the filopodial structures at the growing end.

Structure	Level	Pattern	Image	Note
TS21: brain vascular element	Present		5	Filopodia and processes at the leading edge of the vessels are devoid of anti-laminin staining.

Structure	Level	Pattern	Image	Note
TS21: brain vascular element	Present		6A	Stained filopodial processes emanated from capillaries at the pial surface and extended toward the ventricular epithelium.

Structure	Level	Pattern	Image	Note
TS21: brain vascular element	Present		6B	Stained filopodial processes emanated from capillaries at the pial surface and extended toward the ventricular epithelium.

Structure	Level	Pattern	Image	Note
TS21: brain vascular element	Present		6C	Stained filopodial processes emanated from capillaries at the pial surface and extended toward the ventricular epithelium.

Structure	Level	Pattern	Image	Note
TS12: dorsal aorta	Present
TS12: heart	Present

Structure	Level	Pattern	Image	Note
TS13: blood island	Present
TS13: yolk sac endoderm	Present
TS13: yolk sac mesenchyme	Present

Structure	Level	Pattern	Image	Note
TS14: yolk sac	Present			There were approximately 3,000 Cd34-positive hematopoietic cells per yolk sac.