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内容简介 |
Tissue Engineering & Regeneration (TE/TR) involves the ex vivo production and replacement of organs and tissues using cell precursors and natural products &/or synthetic biomaterials as scaffolds to support the repair, regeneration and/or remodelling and eventual structural or functional replacement of injured, diseased & pathological tissues. There are 3 key ingredients; cells, natural products and synthetic biomaterials. Cells can be derived from autologous (same animal), heterologous (different animal, same species) or xenogenic (different animal species). Autologous cells can be obtained from healthy or diseased tissue sources; e.g. autologous cells for wound healing or heterologous skin cells for interim protection in burn patients. Stem & progenitor cells (e.g. either embryonic or adult mesenchymal stem cells or genetically manipulated cells) are often used in TE/TR technologies. Examples of Natural Products are autologous fibrinogen/fibrin (glues & scaffolds), purified collagen (tissue membranes & sponges) and Coral (for bone replacement & regeneration). Examples of synthetic biomaterials are polylactic acid & polyglycolic acid. These are polymers of two natural products in metabolism (i.e. lactic acid & glycolic acid) that are often used to produce naturally biodegradable scaffolds for TE/TR procedures.There are also synthetic & natural composites; e.g. collagen sponges with glycosaminoglycans, cross-linked hyaluronic acid with integrin binding polypeptide sequences attached to facilitate the recognition and binding of endogenous cell types to the TE/TR scaffolds. Synthetic biomaterials are also used; e.g. polyethylene scaffolds & devices. The disadvantage of these synthetic biomaterials is that they are not biodegradable within the tissues. An example of the use of autologous chondrocyte implantation (ACI) for articular cartilage repair and regeneration will be discussed. |
