Thiol-ene conjugation of VEGF peptide to electrospun scaffolds as potential application for angiogenesis

Tianyu Yao; Honglin Chen; Rong Wang; Rebeca Rivero; Fengyu Wang; Lilian Kessels; Stijn M Agten; Tilman M Hackeng; Tim G A M Wolfs; Daidi Fan; Matthew B Baker; Lorenzo Moroni

doi:10.1016/j.bioactmat.2022.05.029

Thiol-ene conjugation of VEGF peptide to electrospun scaffolds as potential application for angiogenesis

Bioact Mater. 2022 Jun 8:20:306-317. doi: 10.1016/j.bioactmat.2022.05.029. eCollection 2023 Feb.

Authors

Tianyu Yao^{1

2}, Honglin Chen³, Rong Wang⁴, Rebeca Rivero², Fengyu Wang⁵, Lilian Kessels⁶, Stijn M Agten⁷, Tilman M Hackeng⁷, Tim G A M Wolfs^{6

8}, Daidi Fan¹, Matthew B Baker², Lorenzo Moroni²

Affiliations

¹ Shaanxi Key Laboratory of Degradable Biomedical Materials and Shaanxi R&D Center of Biomaterials and Fermentation Engineering, School of Chemical Engineering, Northwest University, Taibai North Road 229, Xi'an, Shaanxi, 710069, China.
² Complex Tissue Regeneration Department, MERLN Institute for Technology Inspired Regenerative Medicine Maastricht University, Maastricht, 6229 ER, the Netherlands.
³ Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China.
⁴ Radboudumc, Department of Dentistry-Regenerative Biomaterials, Radboud University Medical Center, Philips van Leydenlaan 25, 6525 EX, Nijmegen, the Netherlands.
⁵ School of Medicine, South China University of Technology, Guangzhou, 510006, China.
⁶ Department of Pediatrics, Maastricht University Medical Center+, 6229 ER, the Netherlands.
⁷ Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229ER, the Netherlands.
⁸ School for Oncology and Developmental Biology (GROW), Maastricht University, Maastricht, the Netherlands.

Abstract

Vascular endothelial growth factor (VEGF) plays a vital role in promoting attachment and proliferation of endothelial cells, and induces angiogenesis. In recent years, much research has been conducted on functionalization of tissue engineering scaffolds with VEGF or VEGF-mimetic peptide to promote angiogenesis. However, most chemical reactions are nonspecific and require organic solvents, which can compromise control over functionalization and alter peptide/protein activity. An attractive alternative is the fabrication of functionalizable electrospun fibers, which can overcome these hurdles. In this study, we used thiol-ene chemistry for the conjugation of a VEGF-mimetic peptide to the surface of poly (ε-caprolactone) (PCL) fibrous scaffolds with varying amounts of a functional PCL-diacrylate (PCL-DA) polymer. 30% PCL-DA was selected due to homogeneous fiber morphology. A VEGF-mimetic peptide was then immobilized on PCL-DA fibrous scaffolds by a light-initiated thiol-ene reaction. 7-Mercapto-4-methylcoumarin, RGD-FITC peptide and VEGF-TAMRA mimetic peptide were used to validate the thiol-ene reaction with fibrous scaffolds. Tensile strength and elastic modulus of 30% PCL-DA fibrous scaffolds were significantly increased after the reaction. Conjugation of 30% PCL-DA fibrous scaffolds with VEGF peptide increased the surface water wettability of the scaffolds. Patterned structures could be obtained after using a photomask on the fibrous film. Moreover, in vitro studies indicated that scaffolds functionalized with the VEGF-mimetic peptide were able to induce phosphorylation of VEGF receptor and enhanced HUVECs survival, proliferation and adhesion. A chick chorioallantoic membrane (CAM) assay further indicated that the VEGF peptide functionalized scaffolds are able to promote angiogenesis in vivo. These results show that scaffold functionalization can be controlled via a simple polymer mixing approach, and that the functionalized VEGF peptide-scaffolds have potential for vascular tissue regeneration.

Keywords: Electrospun; Fibrous scaffolds; Thiol-ene reaction; VEGF peptide.