Tissue engineering and skeletal diseases

Tissue engineering, a cross between the science of the living organism and that of engineering, aims to replace, maintain or improve human tissue func tions, by means of tissue substitutes containing living elements. Thus, it is about production of artificial tissue, using (alone or in combination) c ells, matrix or bioactive factors. Their association gives rise to a hybrid biomaterial combining biological components (cells, growth factors or adhe sion proteins) and materials (polymers, ceramics). The applications are wid e-ranging, from the skin, to the liver, or to the cornea as well as to the locomotor system. Bone tissue engineering has advanced the most in this fie ld, partly because of the progress made by research into bone substitutes, although cartilage and tendons are also concerned. This technology requires cell culture (committed cells or more often bone marrow stem cells), bioma terials (porous materials with controlled architecture and cements), growth factors (such as 'Bone Morphogenetic Proteins'), the proteins implicated i n cell adhesion (such as fibronectin or the aminoacid sequences specificall y recognised by integrin subunits) or gene therapy (notably using transfect ed stem cells). Tissue engineering and regenerative stimulation of tissue a re now booming on experimental and industrial levels and clinical applicati ons are increasingly numerous. Considering the potential of these technolog ies, they should continue to develop widely. (C) 2000 Editions scientifique s et medicales Elsevier SAS.