Abstract
Repairing or replacing mechanically healthy articular cartilage in a patient's joint should be superior to total joint replacement. Articular cartilage is a unique tissue ensuring the joint elasticity, firmness and - due to self-lubricating surface - a remarkably low friction.
Those articular cartilage injuries that affect the subchondral bone may elicit a fibrous tissue response that is not an adequate replacement of articular cartilage. The transplantation of chondrocytes as a treatment to repair defects in hyaline articular cartilage is a challenging possibility in nowadays orthopaedics.
Chondrocytes are obtained from the non-weight-bearing areas of the affected joint. These chondrocytes are subsequently grown in tissue cultures and transplanted in their intact cartilaginous matrix, as an allograft, to the affected area.
The main problem in use of autologous cell is their dedifferentiation during cultivation in fibroblast-like cells and the decreased number of viable cells. Fibroblasts are not able to produce the basis of extracellular matrix - type II collagen and aggrecan, which are typical for articular cartilage.
The development of three-dimensional cultivation matrices has brought suppression of the phenotypic change and cell loss during cultivation. The preservation of the round shape of cells and better availability of oxygen seems to be crucial.
Chondrocyte transplantation, however, shall require further monitoring for possibly delayed immunogenicity or for any signs of neoplastic potential.