Introduction to tissue engineering and application for cartilage engineering.

Tissue engineering is a multidisciplinary field that applies the principles of engineering, life sciences, cell and molecular biology toward the development of biological substitutes that restore, maintain, and improve tissue function. In Western Countries, tissues or cells management for clinical uses is a medical activity governed by different laws. Three general components are involved in tissue engineering: (1) reparative cells that can form a functional matrix; (2) an appropriate scaffold for transplantation and support; and (3) bioreactive molecules, such as cytokines and growth factors that will support and choreograph formation of the desired tissue. These three components may be used individually or in combination to regenerate organs or tissues. Thus the growing development of tissue engineering needs to solve four main problems: cells, engineering development, grafting and safety studies.