Electrospun tecophilic/gelatin nanofibers with potential for small diameter blood vessel tissue engineering

Abstract

Tissue engineering techniques particularly using electrospun scaffolds have been intensively used in recent years for the development of small diameter vascular grafts. However, the development of a completely successful scaffold that fulfills multiple requirements to guarantee complete vascular regeneration remains challenging. In this study, a hydrophilic and compliant polyurethane namely Tecophilic (TP) blended with gelatin (gel) at a weight ratio of 70:30 (TP(70)/gel(30)) was electrospun to fabricate a tubular composite scaffold with biomechanical properties closely simulating those of native blood vessels. Hydrophilic properties of the composite scaffold induced non-thrombogenicity while the incorporation of gelatin molecules within the scaffold greatly improved the capacity of the scaffold to serve as an adhesive substrate for vascular smooth muscle cells (SMCs), in comparison to pure TP. Preservation of the contractile phenotype of SMCs seeded on electrospun TP(70)/gel(30) was yet another promising feature of this scaffold. The nanostructured TP(70)/gel(30) demonstrated potential feasibility toward functioning as a vascular graft.

Preparation and characterization of small-diameter decellularized scaffolds for vascular tissue engineering in an animal model

“…Most research into TEVG has focused on the use of macromolecular synthetic materials, such as PGA [20, 21], polycaprolactone [27], polypropylene carbonate (PPC) [33], and electrospun tecophilic/gelatin nanofibers [34]. However, these yielded unsatisfactory long-term patency due to thrombotic failure in small-diameter vessels (<6 mm).…”

Impact of electrospun Tecophilic/gelatin scaffold biofunctionalization on proliferation of vascular smooth muscle cells

“…Vasoactivity of contractile SMCs through vascular regeneration may enable the production of functional tissue-engineered blood vessels. We explained the potential of the sca olds to control the phenotypic modulation of SMCs in our previous studies and indicated the preservation of SMCs contractility on electrospun TP(70)/gel(30) sca olds [4,5]. While the proliferation of SMCs seeded on sca olds is generally essential to regenerate a vascular tissue, uncontrollable proliferation in the implanted graft can cause the thickening of the vessel wall and narrowing of the vessel lumen [7].…”

“…The method of electrospinning has been described in our previous studies [4,5]. Brie y, respective polymer solutions prepared in HFP, either TP alone (8% w/v) or TP/gel solution, (8% w/v, with the blend ratio of 70:30 w/w, TP(70)/gel(30)) were individually loaded into a 3 mL plastic syringe tted with a 27 G blunted stainless steel needle.…”

“…During our previous studies, we showed that an electrospun composite sca old using TP and gelatin at a weight ratio of 70:30 could not only support the contractility of SMCs, but also provide appropriate mechanical properties comparable with those of native blood vessels [4,5]. TP is a family of hydrophilic polyether-based thermoplastic aliphatic polyurethane considered as thromboresistance and possesses inherent elasticity [6], suggesting its application as a vascular tissue-engineered graft.…”

“…TP is a family of hydrophilic polyether-based thermoplastic aliphatic polyurethane considered as thromboresistance and possesses inherent elasticity [6], suggesting its application as a vascular tissue-engineered graft. It was found that the addition of gelatin containing many integrin binding sites to TP could improve the potential of the composite sca old to modulate the behavior of SMCs [4,5].…”