Characterization of Bone Marrow and Wharton's Jelly Mesenchymal Stromal Cells Response on Multilayer Braided Silk and Silk/PLCL Scaffolds for Ligament Tissue Engineering.

Xing Liu,Adrien Baldit,Emilie De Brosses,Xiong Wang,Cédric Laurent,Ghislaine Cauchois,Natalia De Isla,Yun Chen,Frédéric Velard

doi:10.3390/polym12092163

Abstract

(1) Background: A suitable scaffold with adapted mechanical and biological properties for ligament tissue engineering is still missing. (2) Methods: Different scaffold configurations were characterized in terms of morphology and a mechanical response, and their interactions with two types of stem cells (Wharton’s jelly mesenchymal stromal cells (WJ-MSCs) and bone marrow mesenchymal stromal cells (BM-MSCs)) were assessed. The scaffold configurations consisted of multilayer braids with various number of silk layers (n = 1, 2, 3), and a novel composite scaffold made of a layer of copoly(lactic acid-co-(e-caprolactone)) (PLCL) embedded between two layers of silk. (3) Results: The insertion of a PLCL layer resulted in a higher porosity and better mechanical behavior compared with pure silk scaffold. The metabolic activities of both WJ-MSCs and BM-MSCs increased from day 1 to day 7 except for the three-layer silk scaffold (S3), probably due to its lower porosity. Collagen I (Col I), collagen III (Col III) and tenascin-c (TNC) were expressed by both MSCs on all scaffolds, and expression of Col I was higher than Col III and TNC. (4) Conclusions: the silk/PLCL composite scaffolds constituted the most suitable tested configuration to support MSCs migration, proliferation and tissue synthesis towards ligament tissue engineering.

Highlights

Ligaments consist of fascicles of dense connective tissue, and play a key role in supporting internal organs and connecting bones together within joints [1,2]
From the present data, considering the combination of mechanical, morphological and biological characterizations of the different scaffold configurations, the novel silk/PLCL composite scaffold appeared adapted to ligament tissue engineering compared with the other tested scaffold configurations
The degradation rate of silk/PLCL should be furtherly characterized to complete the properties of the silk/PLCL scaffold since it has been assumed that the presence of PLCL may reduce the degradation time compared to the same silk scaffold

Summary

Introduction

Ligaments consist of fascicles of dense connective tissue, and play a key role in supporting internal organs and connecting bones together within joints [1,2]. Decades of research have resulted in significant knowledge regarding the biological and mechanical properties of a ligament and the associated grafts used in ligamentoplasty, and have emphasized promising perspectives coming from the field of tissue engineering [3,4,5,6]. One of the milestone for the design of a tissue-engineered ligament is to propose and manufacture a biomaterial-based. Polymers 2020, 12, 2163 construct that could mimic the biological properties, mechanical strength and microstructure of the native ligament tissue [3]. It has been often pointed out that one of the milestone in tissue engineering lies in fostering biomaterials that can restore both biological and mechanical functions [7]. Despite the number of studies that have already been reported, there is still an urgent demand to propose and optimize cell-scaffold constructs with satisfying mechanical properties, biodegradability, morphological and biological properties for ligament tissue regeneration

Methods

Results

Discussion

Conclusion