Osteogenic molecules for clinical applications: improving the BMP-collagen system
Among the osteogenic growth factors used for bone tissue engineering, bone morphogenetic proteins (BMPs) are the most extensively studied for use in orthopaedic surgery. BMP-2 and BMP-7 have been widely investigated for developing therapeutic strategies and are the only two approved for use in several clinical applications. Due to the chemical and biological characteristics of these molecules, their authorised uses are always in combination with a carrier based on collagen type I. Although the
... pe I. Although the use of these growth factors is considered safe in the short term, the very high doses needed to obtain signifi cant osteoinduction make these treatments expensive and their longterm safety uncertain, since they are highly pleiotropic and have the capacity to induce ectopic ossifi cation in the surrounding tissues. Therefore it is necessary to improve the currently used BMP-collagen system in terms of effi ciency, biosecurity and costs. There are several strategies to increase the clinical eff ectiveness of these treatments. In this review we summarize the most promising results and our related work focused on this fi eld through two diff erent approaches: i) the development of recombinant BMPs with additional features, and ii) complementing these systems with other growth factors or molecules to enhance or accelerate osteogenesis.