[Prostaglandin E₂: innovative approaches for tissue engineering of articular cartilage]

Chronic diseases, traumatic tissue defects and tumor resections lead to irreversible loss of tissue which are usually treated by reconstructive techniques or prostheses. Tissue engineering represents a change of paradigm from the structural replacement of damaged tissue to genuine regeneration of organ-specific tissue with reconstruction of function. Therefore, autologous cells, biomaterials and growth factors are used to achieve this goal. Tissue engineering of articular cartilage is used in this article as an example of the successful identification of prostaglandin E2 (PGE2) as a growth factor during endochondral ossification. In addition PGE2 could be shown to be beneficial for a rapid phenotypical redifferentiation and synthesis of collagen II in human articular chondrocytes. Based on these findings the development of a combined construct of an oriented scaffold and release system is demonstrated. The innovative characterization of these cell-seeded constructs by the use of synchrotron microcomputed tomography (μCT) permits non-destructive analysis even down to the cellular level. Our results indicate new requirements for the pathological anatomical diagnosis with a view to long-term effects of tissue engineering constructs, the biocompatibility of biodegradable biomaterials and even more important the regenerative potential of different lesions, with prediction of the outcome of tissue engineering-based strategies for individual patients.