In vivo comparison of the effects of RHBMP-2 and RHBMP-4 in osteochondral tissue regeneration

• Main Authors: F Marco, V Ramos, C Moreno-Vicente, L López-Durán, JL López-Lacomba, Y Lópiz-Morales, A Abarrategi
• Format: Article
• Language: English
• Published: AO Research Institute Davos 2010-12-01
• Series: European Cells & Materials
• Subjects: Biomaterials; cartilage; in vivo; BMP signalling; tissue engineering
• Online Access: http://www.ecmjournal.org/journal/papers/vol020/pdf/v020a30.pdf

The aim of this work is to investigate the use of bone morphogenetic proteins (rhBMP-2, rhBMP-4) alone or in combination with cells delivered in a calcium alginate gel for the treatment of osteochondral defects. For this purpose, alginate gels were prepared mixing a 2% sodium alginate solution and a 200mM calcium chloride solution (1:1). Osteochondral defects were created (4mm wide, 5mm deep) in the internal femoral condyle of rabbit knee and gels were directly formed into the defects. 3 months after surgery samples were harvested, gross morphology was documented and histological appearance was evaluated. The performed histological observations revealed subchondral bone regeneration in rhBMP-2 samples and moderate hyaline cartilage regeneration in rhBMP-4 samples. Thus, results indicate that alginate gel may serve as an appropriate delivery vehicle for rhBMP-2, rhBMP-4 and stromal cells. With this carrier material, differential behaviour between the evaluated proteins was observed. rhBMP-2 shows better restoration of subchondral bone in contrast to the superior efficiency of rhBMP-4 for hyaline cartilage repair.