Advances in biotechnology for tissue engineering of bone.

Tissue engineering is a rapidly developing field applying the disciplines of cell biology, developmental biology, molecular biology and biomimetic engineering to regenerate new tissues for replacement therapies in clinical contexts. To aid in the elicitation and reiteration of the processes of morphogenesis of tissues, the cascade of chemotaxis of progenitor cells, their differentiation and pattern formation is redeployed in postnatal tissues, effected by a variety of ever-increasing morphogens and biomaterials. The extensive recent progress in elucidating the molecular biology of BMPs and their receptors shall aid in promoting and extending the great operational future of this field. Although the BMP family of proteins and osteogenesis have been the subject of several recent reviews, we focus here on their activity in primates and on the novel localization of BMPs in the cerebellum and other areas of the nervous system, and the "mosaicism" of their localisation in the periodontal tissues followed by a discussion on the use of BMPs in periodontal regeneration. Lastly, we report on the unique osteoinductive activity of TGF-beta proteins in heterotopic sites of primates and their synergistic interaction with a recombinant human BMP, and finally we present unique data on novel biomaterials endowed with intrinsic osteoinductive activity, capable of initiating de novo bone formation in heterotopic sites even in the absence of exogenously applied BMPs, and the results of a clinical trial in humans using naturally-derived BMPs.