Biomaterials and Tissue Engineering

Abstract

Tissue engineering, a major technique in regenerative medicine, follows the principles of cell biology, materials science, and engineering to develop biological substitutes that mimic anatomical and functional features of native tissues in order to restore and maintain normal function of injured or diseased tissues [1–4]. Currently, tissue engineering strategies can be divided into two major categories: cell-based and scaffold-based approaches. The classic tissue engineering approach (combined by cells and scaffolds) attempts to create an engineered tissue construct by combining cells with a natural and/or synthetic scaffold material under suitable culture conditions. The scaffold-based tissue engineering approach is more dependent on the body’s natural ability to regenerate for proper orientation and direction of new tissue growth and the use of matrices with cells. These cell-free scaffolds can be prepared by manufacturing artificial scaffolds derived from natural or synthetic materials or by removing cellular components from tissues using mechanical and chemical manipulation to produce collagen-based tissue matrices [5–9]. These natural/synthetic scaffolds slowly degrade following implantation and are subsequently replaced by the extracellular matrix (ECM) proteins secreted by the in-growing cells. Additionally, cells can be used for therapy via injection either with carriers, such as hydrogels, or alone [10].