Heparin coated decellularized xenogeneic small diameter vascular conduit for vascular repair with early luminal reendothelialization.

Small diameter vascular graft is a clinical need in cardiovascular disease (CAD) and peripheral atherosclerotic diseases (PAD). Autologous graft has limitations in availability and harvesting surgery. To make luminal surface modification with heparin coating in xenogeneic small diameter vascular graft. We constructed a conduit from decellularized human saphenous vein (HSV) matrices in small diameter vascular graft (< 0.8 mm diameter). Luminal surface modification was done with heparin coating for transplantation in the rat femoral artery. Biocompatibility of conduit was checked in Chorioallantoic Membrane (CAM) assay and in vivo. The blood flow rate in conduit grafts was measured, and immuno-histological analysis was performed. CAM assay and in vivo biocompatibility test showed cellular recruitment in the HSV scaffold. Heparin binding was achieved on the luminal surface. After three months of transplantation surgery neo-intimal layer was formed in the graft. The graft was patent for two weeks after surgery. There were no statistically differences between blood flow rate in graft (at proximal end 0.5 ± 0.01 m/s and at distal end 0.4 ± 0.01 m/s (n = 6)) and native artery (0.6 ± 0.1 m/second, (n = 3)). Biomarkers of endothelial cells, medial smooth muscle cells, and angiogenesis were observed in the transplanted graft. Our study demonstrates that xenogeneic decellularized vascular grafts with surface modification with heparin coating could be useful for the replacement of small diameter vessels.

Tissue engineered human ear pinna derived from decellularized goat ear cartilage: clinically useful and biocompatible auricle construct.

Surgery of the entire ear pinna even today presents a challenge to reconstructive surgeons, in the absence of a universally acceptable, quality construct for clinical use. In this article, the authors present a technique to generate a flexible, human size ear with the aim to meet this limitation for ear reconstructive surgeries. The construct was engineered by using a decellularized goat ear cartilage. This was characterized by hematoxylin-eosin (H/E), diamidino-2-phenylindole (DAPI), Masson's trichrome (MT), Alcian Blue (AB) staining and Scanning Electron Microscopy (SEM) for extracellular matrix (ECM) analysis. The decellularization protocol followed yielded complete removal of all cellular components without changing the properties of the ECM. In vivo biocompatibility of the ear pinna showed demonstrable recellularization. Recellularization was tracked using HE, DAPI, MT, AB staining, toluidine staining, SEM, vascular-associated protein (VAP) and CD90+ expressing cells. VAP expression revealed specific vasculogenic pattern (angiogenesis). CD90+ expression reflected the presence of the stromal cell. The graft maintained the properties of ECM and displayed chondrocyte recruitment. In summary, the decellularized goat ear pinna (cartilage) exhibited xenograft biocompatibility, stable mechanical properties and in vivo chondrocyte recruitment. Subsequently developed tissue-engineered ear pinna offer potential for cartilage flexibility and individualization of ear shape and size for clinical application.