Response of Dermal Fibroblasts to Biochemical and Physical Cues in Aligned Polycaprolactone/Silk Fibroin Nanofiber Scaffolds for Application in Tendon Tissue Engineering

Abstract

Silk fibroin (SF) and fiber alignment were introduced into polycaprolactone (PCL)-based electrospun nanofibers as chemical and physical cues for tendon tissue engineering applications. The physicochemical properties of random PCL (RP) nanofibers, random PCL/SF (RPSF) nanofibers and aligned PCL/SF (APSF) nanofibers were characterized for fiber orientation and SF blending effects. An in vitro cell culture with rabbit dermal fibroblasts (RDFBs) on nanofibers indicated that SF promotes cell proliferation to a higher extent than fiber alignment. Cells aligned in the direction of fiber axes could be confirmed through scanning electron microscopy (SEM) observation and cytoskeleton staining. The quantitative real-time polymerase chain reaction (qRT-PCR) experiments indicated up-regulated gene expression of tendon marker proteins (type I collagen (Col I), fibronectin and biglycan) on APSF nanofibers and tendon reconstruction was confirmed from Col III gene expression. Animal experiments with Achilles tendon defect repairs in rabbits were carried out with RPSF and APSF scaffolds. The beneficial effects of fiber alignment were verified from histological and immunohistochemical staining, where cell migration and extracellular matrix protein deposition tend to stretch in a parallel direction along the axial direction of APSF nanofibers with enhanced Col I and tenascin C production. Biomechanical testing indicated the tensile stiffness and maximum load of cell-seeded APSF scaffolds were 60.2 and 81.3% of normal tendon values, respectively, which are significantly higher than cell-seeded RPSF or acellular APSF and RPSF scaffolds. These results suggest that APSF nanofiber scaffolds combined with RDFBs have the potential to repair the gap defects of Achilles tendons in vivo and to effectively restore the function and structure of tendons.

Comparison of Different Approaches to Surface Functionalization of Biodegradable Polycaprolactone Scaffolds

“…Bone tissue consists of different types of bone cells (osteoblasts, osteocytes, and osteoclasts) and a mineralization matrix formed by collagen nanofibers and nano-hydroxyapatite (nano-HA) [2]. Since the nanofiber structure is similar to the extracellular matrix, which is an important controller of cell adhesion, proliferation, migration, and differentiation, nanofiber is a promising structural element for scaffold fabrication [3][4][5]. Due to its simplicity and good reproducibility, electrospinning is a widely used method for the production of polymer, ceramics, and metal nanofibers.…”

Synergetic effect of chemical and topological signals of gingival regeneration scaffold on the behavior of human gingival fibroblasts

“…The functionalities of electrospun scaffolds can be affected by fiber diameter, surface chemistry, and topology, and the internal structure of the nanofibers (Matsumoto & Tanioka, ). Generally, the typical electrospun membrane is collected in a random orientation and exhibits isotropic mechanical properties (Chen, Chen, Kuo, Li, & Chen, ). To improve the mechanical strength and supply a topological signal for attached cells, aligned electrospun fibers were fabricated (Yang, Deng, Chen, Ye, & Mo, ).…”

“…Generally, the typical electrospun membrane is collected in a random orientation and exhibits isotropic mechanical properties (Chen, Chen, Kuo, Li, & Chen, 2017). To improve the mechanical strength and supply a topological signal for attached cells, aligned electrospun fibers were fabricated (Yang, Deng, Chen, Ye, & Mo, 2014).…”

Water‐insoluble amorphous silk fibroin scaffolds from aqueous solutions

“…Regenerated silk fibroin (RSF), derived from the silkworm cocoon, is a useful biomaterial as a cell‐support matrix for osteoblasts, endothelial cells, nerve cells and various stem cells, as a scaffold for bone, cartilage, muscle, blood vessels, skin and nerves, and as a carrier for hydrophilic and hydrophobic drugs and growth factors (Chen, Chen, Kuo, Li, & Chen, ; Crivelli et al, ; Farè et al, ; Font Tellado et al, ; Font Tellado et al, ; Hennecke et al, ; Jo et al, ; Kundu, Rajkhowa, Kundu, & Wang, ; Le, Liaudanskaya, Bonani, Migliaresi, & Motta, ; Moses, Nandi, & Mandal, ; Musson et al, ; Sell, McClure, Ayres, Simpson, & Bowlin, ; Teuschl et al, ; Woloszyk, Buschmann, Waschkies, Stadlinger, & Mitsiadis, ; Y. P. Zhang et al, ). Besides the inherent virtues of silk fibroin, such as biocompatibility, a green formation process, and tunable biodegradability, another feature is its diversity of conformations, hierarchical microstructures and various material states, endowing the possibility of designing biomaterials with selective and useful performance (Gorenkova et al, ; Hu et al, ; Kumar, Nandi, Kaplan, & Mandal, ; Qi et al, ; Rockwood et al, ).…”