title: Combining electrospinning and fused deposition modeling for the fabrication of a hybrid vascular graft.
abstract: Tissue engineering of blood vessels is a promising strategy in regenerative medicine with a broad spectrum of potential applications. However, many hurdles for tissue-engineered vascular grafts, such as poor mechanical properties, thrombogenicity and cell over-growth inside the construct, need to be overcome prior to the clinical application. To surmount these shortcomings, we developed a poly-L-lactide (PLLA)/poly-epsilon-caprolactone (PCL) scaffold releasing heparin by a combination of electrospinning and fused deposition modeling technique. PLLA/heparin scaffolds were produced by electrospinning in tubular shape and then fused deposition modeling was used to armor the tube with a single coil of PCL on the outer layer to improve mechanical properties. Scaffolds were then seeded with human mesenchymal stem cells (hMSCs) and assayed in terms of morphology, mechanical tensile strength, cell viability and differentiation. This particular scaffold design allowed the generation of both a drug delivery system amenable to surmount thrombogenic issues and a microenvironment able to induce endothelial differentiation. At the same time, the PCL external coiling improved mechanical resistance of the microfibrous scaffold. By the combination of two notable techniques in biofabrication--electrospinning and FDM--and exploiting the biological effects of heparin, we developed an ad hoc differentiating device for hMSCs seeding, able to induce differentiation into vascular endothelium.
authors.affiliation: Laboratory of Chemistry and Biomaterials, CIR-Center of Integrated Research, University Campus Bio-Medico of Rome, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Centola
authors.forename: A
authors.initials: A
authors.lastname: Rainer
authors.forename: C
authors.initials: C
authors.lastname: Spadaccio
authors.forename: S
authors.initials: S
authors.lastname: De Porcellinis
authors.forename: J A
authors.initials: JA
authors.lastname: Genovese
authors.forename: M
authors.initials: M
authors.lastname: Trombetta
mesh_terms: D000704:Analysis of Variance; D001672:Biocompatible Materials; D001709:Biotechnology; D001807:Blood Vessel Prosthesis; D003692:Delayed-Action Preparations; D055664:Electrochemical Techniques / Q000379:methods*; D004730:Endothelium, Vascular / Q000166:cytology; D006493:Heparin; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry; D059630:Mesenchymal Stem Cells / Q000166:cytology; D018613:Microscopy, Confocal; D011091:Polyesters / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds
chemical_list: D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D011091:Polyesters; D011108:Polymers; C016240:polycaprolactone; D019344:Lactic Acid; C033616:poly(lactide); D006493:Heparin