Antibody:	anti-type VIII collagen
Detection system:	Biotinylated secondary antibody/[Strept]avidin coupled to horseradish peroxidase
Assay notes:	Tissue was fixed in Karnovsky's solution (2.5% glutaraldehyde, 3% paraformaldehyde in 0.1 M sodium cacodylate). The antibody used in this assay recognizes both Col8a1 and Col8a2.

Structure	Level	Pattern	Image	Note
TS19: heart	Present		3A
TS19: cardiac muscle tissue	Present		3B , 3A	Expression associated with trabeculae of myoblasts.

Structure	Level	Pattern	Image	Note
TS23: atrium cardiac muscle	Present	Widespread	3C , 3D
TS23: ventricle cardiac muscle	Present	Widespread	3C , 3D
TS23: cardiac muscle tissue	Strong	Regionally restricted	3D	Strong expression in the myocardium, in contrast with the low levels in the newly differentiated mesenchyme of the myocardial basement membrane.

Structure	Level	Pattern	Image	Note
TS20: cardiac muscle tissue	Present	Regionally restricted	4A	Expressed in myoblasts, but not in the myocardial basement membrane.
TS20: endocardial cushion	Present	Regionally restricted	4A	Expressed in myoblasts, but not in the myocardial basement membrane.

Structure	Level	Pattern	Image	Note
TS21: endocardial cushion	Present	Regionally restricted	4B	Discrete expression in the subendocardium and mesenchyme.
TS21: endocardial tissue	Present	Regionally restricted	4B	Intracellular expression in the endocardial epithelium.

Structure	Level	Pattern	Image	Note
TS23: endocardial cushion	Present	Regionally restricted	4C	Increased expression in the subendocardium and mesenchyme.
TS23: endocardial tissue	Present	Regionally restricted	4C	Intracellular expression in the endocardial epithelium.
TS23: cardiac muscle tissue	Present		4C	Less staining in embryonic myocardium.

Structure	Level	Pattern	Image	Note
TS24: heart valve	Strong		4D

Structure	Level	Pattern	Image	Note
TS24: blood vessel	Present	Regionally restricted	5A	Expressed in the subendothelium and media of several large vessels in the heart.

Structure	Level	Pattern	Image	Note
TS24: blood vessel	Strong	Regionally restricted	5B	Expressed in the tunica media of a large vessel in the heart.

Structure	Level	Pattern	Image	Note
TS11: heart	Absent

Structure	Level	Pattern	Image	Note
TS15: heart	Absent

Structure	Level	Pattern	Image	Note
TS17: heart	Present

Structure	Level	Pattern	Image	Note
TS27: heart	Absent
TS27: heart valve	Absent