@article {19679, title = {Enzymatically crosslinked SF/SF-β-TCP scaffolds incorporating Sr- and Zn-ions as hierarchical structures for osteochondral tissue engineering applications}, booktitle = {Bioceramics30}, year = {2018}, month = {2018-10-26 00:00:00}, address = {Nagoya, Japan}, abstract = {

Introduction.\ Bilayeredscaffolds consisting of a cartilage-like layer and an underlying bone-like layer have been proposed for osteochondral (OC) tissue applications. Silk fibroin (SF) exhibit\ high biocompatibility and tunable mechanical propertiesfor OC scaffolding strategies\ [1].Bioresorbable inorganic materials, such as\ β-tricalcium phosphate(β-TCP)combined with SF have shown to increase osteogenesis[2]. Herein, the development of novel monolithic and hierarchical scaffoldscombining\ enzymatically crosslinked\ SF (HRP-SF) and\ ZnSr-doped β-TCP, is reported\ for OC tissue repair/regeneration.

Experimental.\ The bilayered scaffolds were prepared with 80/20 (w/w)\ HRP-SF/undoped and ZnSr-doped β-TCP for the bone-like layers, and HRP-SF as cartilage-like layer. Salt-leaching and freeze-drying technologies were applied to induce macro-/micro-porosity to the scaffolds.\ Physicochemical characterization, structural integrity, and bioactivity of the scaffolds were evaluated. The\ in vitrocell\ adhesion, proliferation and extracellular matrix (ECM) production were evaluated by co-culturing human chondrocytes and human osteoblasts in the scaffolds up to 14 days.

Results and Discussion.\ The results showed an interconnected porosity and homogeneous\ β-TCP distribution into the subchondral bone layer\ (Fig.1a and b).The mechanical properties of ZnSr-doped scaffolds were superior than the undoped scaffolds. Co-cultured cells adhered and proliferated on the bilayered scaffolds (Fig. 1c), showing\ the formation of a mineralized ECM and GAGs deposition in the respective bone and cartilage-like layers.

Conclusions.\ The structural adaptability and suitable mechanical properties of the proposed engineered OC scaffolds, combined with the biological performance achieved using a co-culturing system, make these scaffolds a viable strategy for OC defects regeneration.

References.

[1] L.-P. Yan, J. Silva-Correia, M. Oliveira, et al.,\ Acta biomaterialia\ \ 2015;12:227-241,2015.

[2] S. Pina, R. Canadas, G. Jim{\'e}nez, et al.,\ Cells Tissues Organs2017;204:150.

}, keywords = {Bilayered Scaffold, HRP-mediated silk fibroin hydrogel, Ionicdopants, Osteochondral tissue engineering., β-tricalcium phosphate}, author = {Ribeiro, V. P. and Pina, S. and Costa, J. B. and Cengiz, I. F. and Garc{\'\i}a-Fern{\'a}ndez, L. and Fern{\'a}ndez-Gutierrez, M. and Oliveira, A. L. and San-Rom{\'a}n, J. and Oliveira, J. M. and Reis, R. L.} }