Paracrine cross-talk between human adipose tissue-derived endothelial cells and perivascular cells accelerates the endothelialization of an electrospun ionomeric polyurethane scaffold.

The ex vivo endothelialization of small diameter vascular prostheses can prolong their patency. Here, we demonstrate that heterotypic interactions between human adipose tissue-derived endothelial cells and perivascular cells can be exploited to accelerate the endothelialization of an electrospun ionomeric polyurethane scaffold. The scaffold was used to physically separate endothelial cells from perivascular cells to prevent their diffuse neo-intimal hyperplasia and spontaneous tubulogenesis, yet enable their paracrine cross-talk to accelerate the integration of the endothelial cells into a temporally stable endothelial lining of a continuous, elongated, and aligned morphology. Perivascular cells stimulated endothelial basement membrane protein production and suppressed their angiogenic and inflammatory activation to accelerate this biomimetic morphogenesis of the endothelium. These findings demonstrate the feasibility and underscore the value of exploiting heterotypic interactions between endothelial cells and perivascular cells for the fabrication of an endothelial lining intended for small diameter arterial reconstruction. STATEMENT OF SIGNIFICANCE: Adipose tissue is an abundant, accessible, and uniquely dispensable source of endothelial cells and perivascular cells for vascular tissue engineering. While their spontaneous self-assembly into microvascular networks is routinely exploited for the vascularization of engineered tissues, it threatens the temporal stability of an endothelial lining intended for small diameter arterial reconstruction. Here, we demonstrate that an electrospun polyurethane scaffold can be used to physically separate endothelial cells from perivascular cells to prevent their spontaneous capillary morphogenesis, yet enable their cross-talk to promote the formation of a stable endothelium. Our findings demonstrate the feasibility of engineering an endothelial lining from human adipose tissue, poising it for the rapid ex vivo endothelialization of small diameter vascular prostheses in an autologous, patient-specific manner.