Tissue engineering and scaffolds

Three-dimensional porous scaffolds promote new tissue formation by providing a surface and void volume that promotes the attachment, migration, 

Another option is bioresorbable sUk. The silk matrix is an appropriate three-dimension culture environment for cell attachment and spreading after being processed to extract the allergen component, sericin. The development of twisted fiber architecture gives the scaffold excellent 

Another aspect to consider is the cell source, cellular response and cellular affinity for the scaffold. ACL fibroblasts were shown to respond to specific growth factors, dynamic mechanical stimulation and static tension, but are known to have a low doubling rate, and a suitable source of autologous ACL fibroblasts is not yet available. This is why other sources, such as mesenchymal stem cells from bone marrow, are under investigation and seem to be an excellent cell source. They have the potential to differentiate into cells of multiple mesenchymal lineages.  

Clinical studies to date, however, have been infrequent and inconsistent. Jadeja et al. reviewed a composite carbon-fiber polyester scaffold used in ACL-deficient knees at their institutions (ABC - Active Biosynthetic Composite Ligament).It was introduced in 1985 and is made of 24 strands of interwoven carbon and polyester unit material with radial overbraiding and a loop at either end. The over the top technique was used. The early failure of their first cohort was attributed to technical errors. The second cohort showed a very low initial failure rate (0% in the first 3 years) but with an increasing incidence of failure (27.9%) noted after 5 years, mainly at the intra-articular tibial tunnel exit. Another study also using the same ABC scaffold reported 90% satisfaction among their 71 patients with a mean follow-up of 5 years. There were no failures and only two patients suffered from recurrent synovitis.  

As we can see, tissue engineering is an emerging field, but there are still many problems to overcome. Despite extensive research, no materials have achieved the goal of a construct with the biomechanical, biofunctional and biostable properties of a native ACL. It will be interesting to observe what the new generation of scaffolds will bring. 

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Hydrogels as Scaffold Materials 3.8.2.1 Tissue Engineering and Scaffolds... 

Li CQ et al (2009) Construction of collagen II/hyaluronate/chondroitin-6-sulfate tri-copoly-mer scaffold for nucleus pulposus tissue engineering and preliminary analysis of its physicochemical properties and biocompatibility. J Mater Sci Mater Med 21 741-751... 

Nerem R.M., Braddon L.G., Scliktar D., Ziegler T., Tissue engineering and the vascular system in Attala A., Mooney D.J., Vacanti J.P., Langer R. (eds) Synthetic Biodegradable Polymer Scaffolds, Birkhauser, Boston, 1997, 165— 185. 

Baker BM et al (2009) New directions in nanofibrous scaffolds for soft tissue engineering and regeneration. Expert Rev Med Devices 6(5) 515-532... 

Polymer-supported Ag nanoparticles have been widely investigated and provide potential applications as catalysts, photonic and electronic sensors, wound dressings, body wall repairs, augmentation devices, tissue scaffolds, and antimicrobial filters [15-22]. For these applications, Ag nanoparticles have to be supported in a biocompatible polymer system [23-26]. The electrospinning technique has often been adopted for the incorporation of Ag nanoparticles into polymer porous media. In this chapter, we review the preparation methods and properties of Ag nanoparticles incorporated into polymeric nanofibers and their applications in the fields of filtration, catalysis, tissue engineering and wound dressing. 

Functional nanofibrous scaffolds produced by electrospinning have great potential in many biomedical applications, especially tissue engineering and regenerative... 

Simulating the appropriate size, geometry and architecture of natural extracellular matrix is of critical importance for tissue engineering and three-dimensional (3D) tissue culture. Essential parameters for tissue scaffolds are microstructures, porosity, pore size, surface area / surface chemistry and mechanical properties (35). With these properties in mind, several iterations of scaffolds have been produced and evaluated. 

Kharande TS, Agrawal CM (2008) Functions and requirements of synthetic scaffolds in tissue engineering. In Laurencin CT, Nair LS (eds) Nanotechnology and tissue engineering the scaffold. CRC, Boca Raton... 

In Muller s work [51], non-woven cellulose II fabrics were used as scaffolds for in vitro cartilage tissue engineering. The scaffolds were activated in a saturated Ca[OH]2 solution and subsequently coated with a calcium phosphate layer precipitated from a supersaturated physiological solution. Chondrocyte cell response and cartilage development were investigated. The cell adherence was significantly improved compared to untreated cellulose fabrics, and the proliferation and vitality of the adhered chondrocytes were excellent, indicating the biocompatibility of these materials. 

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