Browsing by Author "Reis, R. L."
Now showing 1 - 3 of 3
Results Per Page
Sort Options
- Complex 3D architectures using a textile technology for bone tissue engineering applicationsPublication . Ribeiro, V. P.; Ribeiro, A. S.; Silva, C. J.; Durães, N. F.; Bonifácio, G.; Correlo, V. M.; Marques, A. P.; Sousa, R. A.; Oliveira, A. L.; Reis, R. L.Textile-based technologies are particularly interesting in tissue engineering since they allow producing finely tuned fibre-based porous structures, offering superior control over the material design (size, porosity, fibre alignment) and manufacturing. Scaffolds with very reproducible and interconnected intra-architectural geometry can be processed increasing the surface area for cell attachment and tissue ingrowth. This work aims to evaluate the potential of recently developed 3D textile structures based on silk fibroin (SF) to support human Adipose-derived Stem Cells (hASCs) adhesion, proliferation and osteogenic differentiation. These cells constitute an emerging possibility for regenerative medicine, including for bone tissue regeneration. A comparative analysis was performed with a more stable polymeric system, polyethylene terephthalate (PET). SF and PET yarns were processed into 3D spacer structures using warp-knitting technology. The obtained complex 3D architectures are composed of two knitted layers assembled/spaced by a PET monofilament to increase the tri-dimensionality of the scaffold. Cells were able to attach to the fibres, proliferate and differentiate into the osteogenic lineage. hASCs were able to deeply penetrate into the scaffold and colonize its interior with great evidences of extracellular matrix mineralization (Fig.1). The efficiency and high level of control of the warpknitting technology together with the interesting structural properties of the resulting constructs makes this a very versatile and adaptable system to the specific bone tissue anatomy and function.
- Evaluation of novel 3D architectures based on knitting technologies for engineering biological tissuesPublication . Ribeiro, V. P.; Ribeiro, A. S.; Silva, J. C.; Durães, N. F.; Bonifácio, G.; Correlo, V. M.; Marques, A. P.; Sousa, R. A.; Oliveira, A. L.; Reis, R. L.Textile-based technologies are considered as potential routes for the production of 3D porous architectures for tissue engineering applications. We describe the use of two polymers, namely polybutylene succinate (PBS) and silk fibroin (SF) to produce fiber-based finely tuned porous architectures by weft and warp knitting. The obtained knitted constructs are described in terms of their morphology, mechanical properties, swelling ability, degradation behaviour and cytotoxicity. Each type of polymer fibers allow for the processing of a very reproducible intra-architectural scaffold geometry, with distinct characteristics in terms of the surface physicochemistry, mechanical performance and degradation capability, which has an impact on the resulting cell behaviour at the surface of the respective biotextiles. Preliminary cytotoxicity screening shows that both materials can support cell adhesion and proliferation. Furthermore, different surface modifications were performed (acid/alkaline treatment, UV radiation and plasma) for modulating cell behavior. An increase of cell- material interactions were observed, indicating the important role of materials surface in the first hours of culturing. Human Adipose-derived Stem Cells (hASCs) became an emerging possibility for regenerative medicine and tissue replacement therapies. The potential of the recently developed silk- based biotextile structures to promote hASCs adhesion, proliferation and differentiation is also evaluated. The obtained results validate the developed constructs as viable matrices for TE applications. Given the processing efficacy and versatility of the knitting technology, and the interesting structural and surface properties of the proposed polymer fibers, it is foreseen that our developed systems can be attractive for the functional engineering of tissues such as bone, skin, ligaments or cartilage and also for develop more complex systems for further industrialization of TE products.
- In vitro evaluation of the biological performance of macro/ micro-porous silk fibroin and silk-nano calcium phosphate scaffoldsPublication . Yan, L.-P.; Oliveira, J. M.; Oliveira, A. L.; Reis, R. L.This study evaluates the biological performance of salt-leached macro/microporous silk scaffolds (S16) and silk-nano calcium phosphate scaffolds (SC16), both deriving from a 16 wt % aqueous SF solution. Enzymatic degradation results showed that the silk-based scaffolds presented desirable biostability, and the incorporation of calcium phosphate further improved the scaffolds' biostability. Human adipose tissue derived stromal cells (hASCs) were cultured onto the scaffolds in vitro. The Alamar blue assay and DNA content revealed that both scaffolds were non-cytotoxic and can support the viability and proliferation of the hASCs. Scanning electron microscopy observation demonstrated that the microporous structure was beneficial for the cell adhesion while the macroporous structure favored the cell migration and proliferation. The histological analysis displayed abundant extracellular matrix formed inside the scaffolds, leading to the significant increase of scaffolds' modulus. These results revealed that S16 and SC16 could be promising alternatives for cartilage and bone tissue engineering scaffolding applications, respectively.