Making a scaffold: Given the lack of cell retention when cell suspensions are directly transplanted at the cartilage defect site, porous three-dimensional scaffolds are increasingly being used to facilitate cellular attachment while providing superior mechanical properties. The scaffold should provide a temporary three-dimensional template for the seeded cells to adhere and subsequently to synthesize new target-tissue-specific extracellular matrix (ECM) in a shape and form guided, at least initially, by the scaffold. The main criteria for scaffold design include controlled biodegradability, suitable mechanical strength and appropriate surface chemistry, which together regulate cellular activities, such as proliferation, cell–cell and cell–matrix interactions, and directed differentiation. Scaffolds are molds in the shape of organs and tissues and are the building blocks of regenerative medicine. These scaffolds are "seeded" with cells and support them as they grow and develop. Scaffolds are the essential components of tissue engineering efforts. The ideal biomaterial is one that is compatible with the body, promotes cell growth and degrades into the body once the engineered tissue has fully integrated with existing tissue. We employ hydrogels and nanofibers to produce scaffolds mimicking the physical and mechanical properties of the host tissue and to ensure cell survival, direct appropriate differentiation, and promote maximal integration.
Ultrastructural morphology of acellular Nanofibrous scaffold examined by SEM. Poly-L-lactic acid (PLLA) NFS produced by the electrospinning process show random orientation of ultrafine fibers with a diameter ranging from 500–900 nm, defining a matrix with interconnecting pores.
- Hang Lin
- Riccardo Gottardi