Core–Shell Pure Collagen Threads Extruded from Highly Concentrated Solutions Promote Colonization and Differentiation of C3H10T1/2 Cells

• Published in: ACS biomaterials science & engineering 2021-02, Vol.7 (2), p.626-635
• Main Authors: Picaut, Lise, Trichet, Léa, Hélary, Christophe, Ducourthial, Guillaume, Bonnin, Marie-Ange, Haye, Bernard, Ronsin, Olivier, Schanne-Klein, Marie-Claire, Duprez, Delphine, Baumberger, Tristan, Mosser, Gervaise
• Format: Article
• Language: English
• Subjects: Bioengineering; Biomaterials; Cell Differentiation; Collagen; Condensed Matter; Fluid Dynamics; Imaging; Life Sciences; Mesenchymal Stem Cells; Physics; Soft Condensed Matter; Tissue Engineering; Tissue Engineering and Regenerative Medicine; Tissue Scaffolds
• ISSN: 2373-9878; 2373-9878
• DOI: 10.1021/acsbiomaterials.0c01273

The elaboration of scaffolds able to efficiently promote cell differentiation toward a given cell type remains challenging. Here, we engineered dense type I collagen threads with the aim of providing scaffolds with specific morphological and mechanical properties for C3H10T1/2 mesenchymal stem cells. Extrusion of pure collagen solutions at different concentrations (15, 30, and 60 mg/mL) in a PBS 5× buffer generated dense fibrillated collagen threads. For the two highest concentrations, threads displayed a core–shell structure with a marked fibril orientation of the outer layer along the longitudinal axis of the threads. Young’s modulus and ultimate tensile stress as high as 1 and 0.3 MPa, respectively, were obtained for the most concentrated collagen threads without addition of any cross-linkers. C3H10T1/2 cells oriented themselves with a mean angle of 15–24° with respect to the longitudinal axis of the threads. Cells penetrated the 30 mg/mL scaffolds but remained on the surface of the 60 mg/mL ones. After three weeks of culture, cells displayed strong expression of the tendon differentiation marker Tnmd, especially for the 30 mg/mL threads. These results suggest that both the morphological and mechanical characteristics of collagen threads are key factors in promoting C3H10T1/2 differentiation into tenocytes, offering promising levers to optimize tissue engineering scaffolds for tendon regeneration.