Vascular endothelial growth factor in porcine-derived extracellular matrix

An extracellular matrix (ECM) derived from the submucosa of the porcine sma ll intestine (SIS) has been shown to induce angiogenesis and host tissue re modeling when used as a xenogeneic bioscaffold in animal models of wound re pair. In the present study, we compared the in vitro effects of SIS ECM ext racts to several purified angiogenic growth factors on human dermal microva scular endothelial cell (HMEC) growth patterns. The SIS ECM was shown to in duce tube formation from HMEC in a three-dimensional fibrin-based angiogene sis assay in a manner similar to that caused by the addition of vascular en dothelial growth factor (VEGF). This tube formation was blocked in the pres ence of anri-VEGF neutralizing antibody. Western blots and ELISA procedures showed that the SIS ECM contains as much as 0.77 ng VEGF/g SIS. The closel y related endothelial cell mitogen, platelet-derived growth factor (PDGF), was not detectable in the SIS extracts. We conclude that VEGF is present in the SIS extracellular matrix. The role of VEGF In SIS-induced wound repair remains unknown, but its presence in the ECM makes it a possible contribut or to the angiogenic effect of SIS when this ECM is used as a tissue repair scaffold in animal models of wound repair.