Healing of PTFE Grafts in a Pig Model Recruit Neointimal Cells from Different Sources and Do Not Endothelialize

Abstract

Our study suggests that in artificial porcine grafts, the perivascular tissue, the blood and the adjacent artery contribute to the formation of the neointima. The luminal surface is covered by a hybrid cell with both smooth muscle cell and endothelial cell properties.

The evaluation of a small-diameter polysaccharide-based arterial graft in rats

“…In our case, no interstitial growth of tissue could be evidenced within the gel. Even though perigraft tissue infiltration has been reported to stabilize and enhance the vascular tissue regeneration [22], the nylon mesh in our model provided a protective effect from tissue ingrowth by limiting a direct contact between the graft and the surrounding tissue [23]. We can assume that the intimal cells do not come from the anastomosis edges, since (1) the presence of decellularised aorta segments prevents the migration of more than 1 cm of the cells from the native aorta towards the centre of the polysaccharide graft, and (2) a uniform intima is observed all along the graft at early time point (1 week).…”

“…We can assume that the intimal cells do not come from the anastomosis edges, since (1) the presence of decellularised aorta segments prevents the migration of more than 1 cm of the cells from the native aorta towards the centre of the polysaccharide graft, and (2) a uniform intima is observed all along the graft at early time point (1 week). Mellander et al [23] reported the healing process of a PTFE prosthesis as a pronounced infiltration of leukocytes into the graft, which was followed in sequence by cellular proliferation and formation of a neointima. Studies have suggested that monocytes/macrophages have the ability to change their phenotypes into SMC-like cells [24].…”

Small Vessel Replacement by Human Umbilical Arteries With Polyelectrolyte Film-Treated Arteries

“…4C and 4D): 1) the presence of the expected chronic inflammatory cells in arterial adventitia (Figs. 4C and 4D, dotted arrows) probably due to the healing process (29); 2) the disappearance of the cells from the media (Figs. 4C and 4D, black arrows) due to the absence of vasa vasorum, leading to apoptosis or necrosis of cells (30,31); and 3) the presence of PEM and its regular coating on the internal surface, visualized by H&S (Figs.…”

A Reproducible Porcine ePTFE Arterial Bypass Model for Neointimal Hyperplasia

“…There are some established porcine prosthetic arterioarterial bypass models [19,22]. However, when we began to consider models of arterial bypass grafting, we considered the following possibilities: aorto-common iliac, common iliac-common iliac, common iliac-external iliac, or common iliac-femoral artery bypass grafting.…”

“…Currently described porcine restenosis models with prosthetic materials include variations of arteriovenous and arterio-arterial bypass grafts [17][18][19][20][21][22][23]. The arterio-venous bypass graft represents a different pathophysiologic process that results in neointimal hyperplasia when compared to arterial reconstruction [24].…”