Biomaterials: Tissue Engineering and Scaffolds

Tissue engineering offers an alternative to whole organ and tissue transplantation for diseased, failed, or abnormally functioning organs. Tissue engineering requires a triad of components: (1) Harvested and dissociated cells from the donor tissue; (2) scaffolds made of biomaterials on which cells are attached and cultured, then implanted at the desired site in functioning tissue; and (3) growth factors that promote and/or prevent cell adhesion, proliferation, migration, and differentiation by up-regulating or down-regulating the synthesis of protein, growth factors, and receptors. Of these three key components, scaffolds be play a critical role. Scaffolds direct the growth 1993 of cells seeded within the porous structure of the scaffold, or 1995 of cells migrating from the surrounding tissue, to eventually mimick a natural extracellular matrix. In this section, a review is given of the biomaterials and procedures used in the development of tissue-engineered scaffolds, including: (1) natural and synthetic, polymeric biomaterials (2) bioceramic scaffolds, (3) cytokine-released scaffolds, (4) the fabrication and characterization of scaffolds, (5) surface modifications, and (6) scaffold sterilization. However, to approach a more natural three-dimensional environment necessary for successful organ and tissue transplantation, the combined efforts of researchers from the fields of biology, biochemistry, and material science/engineering will be needed to further develop scaffolds that will support biological signals for tissue growth and reorganization.