Affiliation:
1. Weldon School of Biomedical Engineering Purdue University West Lafayette Indiana USA
2. Department of Orthopaedic Surgery Washington University St. Louis Missouri USA
3. Shriners Hospitals for Children–St. Louis St. Louis Missouri USA
4. Department of Basic Medical Sciences Purdue University West Lafayette Indiana USA
Abstract
AbstractTendon tears are common and healing often occurs incompletely and by fibrosis. Tissue engineering seeks to improve repair, and one approach under investigation uses cell‐seeded scaffolds containing biomimetic factors. Retention of biomimetic factors on the scaffolds is likely critical to maximize their benefit, while minimizing the risk of adverse effects, and without losing the beneficial effects of the biomimetic factors. The aim of the current study was to evaluate cross‐linking methods to enhance the retention of tendon‐derived matrix (TDM) on electrospun poly(ε‐caprolactone) (PCL) scaffolds. We tested the effects of ultraviolet (UV) or carbodiimide (EDC:NHS:COOH) crosslinking methods to better retain TDM to the scaffolds and stimulate tendon‐like matrix synthesis. Initially, we tested various crosslinking configurations of carbodiimide (2.5:1:1, 5:2:1, and 10:4:1 EDC:NHS:COOH ratios) and UV (30 s 1 J/cm2, 60 s 1 J/cm2, and 60 s 4 J/cm2) on PCL films compared to un‐crosslinked TDM. We found that no crosslinking tested retained more TDM than coating alone (Kruskal‐Wallis: p > .05), but that human adipose stem cells (hASCs) spread most on the 60 s 1 J/cm2 UV‐ and 2.5:1:1 EDC‐crosslinked films (Kruskal‐Wallis: p < .05). Next, we compared the effects of 60 s 1 J/cm2 UV‐ and 2.5:1:1 EDC‐crosslinked to TDM‐coated and untreated PCL scaffolds on hASC‐induced tendon‐like differentiation. UV‐crosslinked scaffolds had greater modulus and stiffness than PCL or TDM scaffolds, and hASCs spread more on UV‐crosslinked scaffolds (ANOVA: p < .05). Fourier transform infrared spectra revealed that UV‐ or EDC‐crosslinking TDM did not affect the peaks at wavenumbers characteristic of tendon. Crosslinking TDM to electrospun scaffolds improves tendon‐like matrix synthesis, providing a viable strategy for improving retention of TDM on electrospun PCL scaffolds.
Funder
National Institutes of Health
National Institute of Arthritis and Musculoskeletal and Skin Diseases
Subject
Metals and Alloys,Biomedical Engineering,Biomaterials,Ceramics and Composites