@article {18389, title = {Textile-based Silk Scaffolds for Bone Tissue Engineering Applications}, journal = {27th European Conference on Biomaterials ESB2015}, year = {2015}, month = {2015-04-20 00:00:00}, address = {Krak{\'o}w, POLAND}, abstract = {

INTRODUCTION

Scaffolds developed for bone tissue engineering (TE) need to facilitate and promote cell adhesion, proliferation and neo-tissue formation. They must possess specific properties to allow the new tissue to integrate with the material, without inducing any inflammatory response1. The intra-architectural scaffold geometry, porosity, scaffold material and surface area play important roles in this process 2. Several polymeric systems (natural and/or synthetic) and processing methods and have been proposed to develop the {\textquotedblleft}ideal{\textquotedblright} scaffold for bone TE. However, so far the proposed strategies do not fulfil all the requirements for effective bone regeneration. Textile-based technologies constitute an innovative alternative for the production of 3D structures for bone TE applications, offering a superior control over scaffolds{\textquoteright} design, manufacturing and reproducibility3. Silk fibroin (SF) derived from silkworm Bombyx mori has already proved to be a good biomaterial for bone TE applications4. SF-based structures offer impressive mechanical properties, biodegradability, biocompatibility and stability, which meets the basic requirements for the design of structures for bone regeneration applications5.

EXPERIMENTAL METHODS

In this work we describe for the first time the processing of natural silk yarns into 3D scaffolds, combining standard knitting fabrics spaced by a monofilament of polyethylene terephthalate (PET). A comparative study is established using a stable polymeric system made entirely of PET. The obtained knitted spacer constructs were described in terms of morphology and mechanical properties. An in vitro biological assay was performed to evaluate the potential of the developed structures to support human Adipose-derived Stem Cells (hASCs) adhesion, proliferation and osteogenic differentiation. Cells were cultured over 28 days in standard basal and osteogenic conditions and evaluated through different quantitative (DNA, ALP, Calcium, RT-PCR) and qualitative (SEM, Alizarin Red, immunocytochemistry) assays. The in vivo biocompatibility of the textile materials was assessed by subcutaneous implantation in mice model. After 2 and 4weeks of implantation the explants were collected and the obtained slides were stained with hematoxylin and eosin (H\&E).

RESULTS AND DISCUSSION

The cross-sections of the developed spacer textile constructs reveal a significant increase of the scaffolds three-dimensionality induced by the PET monofilament (Figure 1a). The hASCs seededonto the spacer textile scaffolds were able to attach, spread, proliferate and differentiate, both in osteogenic and basal conditions (Figure 1b). Great evidences of ECM mineralization were observed, also penetrating and colonizing the PET monofilament (Figure 1a). The preliminary in vivo results revealed that the implanted scaffolds allowed tissue ingrowth, without inducing any acute inflammatory reaction (Figure 1c).

CONCLUSION

In this study, innovative 3D biotextile scaffolds able to support cell adhesion, proliferation and osteogenesis were successfully developed. Furthermore, these scaffolds allowed the new tissue formation and integration within the material, when subcutaneously implanted in mice. Thus, the proposed textile-based scaffolds can be promising candidates for bone TE applications such as the craniomaxilofacial complex6.

}, keywords = {3D biotextile, Bone Tissue Engineering, Human adipose-derived stem cells, Knitting, Spacer, Silk Fibroin}, author = {Ribeiro, V. P. and Morais, A. and Correlo, V. M. and Marques, A. P. and Ribeiro, A. S. and Silva, C. J. and Dur{\~a}es, N. F. and Bonif{\'a}cio, G. and Sousa, R. A. and Oliveira, J. M. and Reis, R. L. and Oliveira, A. L.} }