Distribution of von Willebrand factor in porcine intima varies with blood vessel type and location.

The von Willebrand factor (vWF) has been generally accepted as a marker for endothelial cells. In a systematic immunolocalization study of porcine blood vessels that used indirect immunofluorescence with a monospecific polyclonal anti-vWF and two monoclonal anti-vWFs, we observed that vWF is not universally distributed in intact, fresh endothelia. vWF is consistently localized in veins, with the exception of the pulmonic vein. In arteries, vWF is generally absent except for areas of the distal abdominal aorta, the vaso vasorum of the thoracic aorta, and the pulmonic artery. We conclude that there are regional differences in the distribution of vWF in the various endothelial beds of pigs.