Conjugation with RGD Peptides and Incorporation of Vascular Endothelial Growth Factor Are Equally Efficient for Biofunctionalization of Tissue-Engineered Vascular Grafts

Abstract

The blend of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and poly(ε-caprolactone) (PCL) has recently been considered promising for vascular tissue engineering. However, it was shown that PHBV/PCL grafts require biofunctionalization to achieve high primary patency rate. Here we compared immobilization of arginine–glycine–aspartic acid (RGD)-containing peptides and the incorporation of vascular endothelial growth factor (VEGF) as two widely established biofunctionalization approaches. Electrospun PHBV/PCL small-diameter grafts with either RGD peptides or VEGF, as well as unmodified grafts were implanted into rat abdominal aortas for 1, 3, 6, and 12 months following histological and immunofluorescence assessment. We detected CD31+/CD34+/vWF+ cells 1 and 3 months postimplantation at the luminal surface of PHBV/PCL/RGD and PHBV/PCL/VEGF, but not in unmodified grafts, with the further observation of CD31+CD34−vWF+ phenotype. These cells were considered as endothelial and produced a collagen-positive layer resembling a basement membrane. Detection of CD31+/CD34+ cells at the early stages with subsequent loss of CD34 indicated cell adhesion from the bloodstream. Therefore, either conjugation with RGD peptides or the incorporation of VEGF promoted the formation of a functional endothelial cell layer. Furthermore, both modifications increased primary patency rate three-fold. In conclusion, both of these biofunctionalization approaches can be considered as equally efficient for the modification of tissue-engineered vascular grafts.

In Situ Vascular Tissue Remodeling Using Biodegradable Tubular Scaffolds With Incorporated Growth Factors and Chemoattractant Molecules

“…The tissue reaction to the subcutaneous implantation of these matrices has been previously discussed in [6]. In addition, we used other vascular graft samples with 2 mm diameter containing VEGF, bFGF, SDF-1a which were previously implanted for a 12-months period in our previous experiments [2,3] to assess the impact of the modification approach of biodegradable vascular grafts on their calcification. These samples were additionally stained with alizarin red and DAPI and subjected to fluorescence microscopy ( Fig.…”

“…Therefore, the development of a functionalized biodegradable vascular prosthesis allowing neovessel formation is of paramount importance [1]. We have previously demonstrated that the incorporation of growth factors and chemoattractant molecules directly into the electrospun tubular polymeric scaffold with 2 mm diameter may enhance its angiogenesis [2,3]. Potential benefits of the layered incorporation of several growth factors and chemoattractant molecules into the scaffold and their influence on the cells have been shown [4].…”

Tissue and organ decellularization in regenerative medicine

“…Peptide motifs from collagen I (GTPGPQGIAGQRGVV), collagen IV (MNYYSNS), fibronectin (PHSRN), laminin (YIGSR) can enhance cell attachment . Arginine‐glycine‐aspartic acid (RGD), a peptide sequence found in fibronectin, vitronectin, laminin, collagen types I and IV, has a high affinity for integrin‐mediated cell attachment and spreading, functionality and tissue development . The RGD sequence co‐immobilized with the SVVYGLR sequence was used to enhance the adhesion of endothelial cells .…”

“…124,125 Arginine-glycineaspartic acid (RGD), a peptide sequence found in fibronectin, vitronectin, laminin, collagen types I and IV, has a high affinity for integrin-mediated cell attachment and spreading, functionality and tissue development. [126][127][128][129][130] The RGD sequence co-immobilized with the SVVYGLR sequence was used to enhance the adhesion of endothelial cells. 123 Three ECMderived peptides, laminin (IKLLI and PDSGR) and cadherin (HAVDI) supported the adhesion and survival of insulincontaining cultures for 5 days.…”

IN SILICO ANALYSIS OF HUMAN VEGF, bFGF, SDF-1α AFFINITY TO RELEVANT HUMAN / OVINE RECEPTORS

“…Поскольку в отсутствие предварительной биофункционализации сосудистые графты малого диаметра не показывают достаточно высокой проходимости [14], с целью улучшения адгезии стволовых и прогениторных клеток и их проникновения в стенку графта активно тестируется стратегия инкорпорирования биоактивных факторов в полимерные каркасы [8,11,15,16]. В частности, нашими коллегами из НИИ КПССЗ изучается эффективность применения комбинации сосудистого эндотелиального фактора роста (vascular endothelial growth factor, VEGF), основного фактора роста фибробластов (basic fi broblast growth factor, bFGF/FGF-2) и фактора стромальных клеток 1α (stromal cell-derived factor, SDF-1α) [17][18][19]. VEGF индуцирует миграцию, пролиферацию и дифференцировку эндотелиальных клеток, ускоряет синтез оксида азота и повышает проницаемость сосудов [11,20,21].…”