Michel Dard

A cyclo peptide activates signaling events and promotes growth and the production of the bone matrix.

The interaction of bone cells and their underlying extracellular matrix impacts biological processes such as maintenance of tissue integrity. The biological recognition of the extracellular matrix by attached cells is mediated by the activity of integrins that recognize adhesive-specific domains. The most widely recognized adhesive motif is the RGD sequence, common to many of the adhesive matrix molecules. Here, we show that cyclo DFKRG which was previously selected to increase cell adhesion of human bone marrow stromal cells (HBMSC), increases both cell differentiation and mineralization through activation of tyrosine kinases, focal adhesion kinase (p(125)FAK) and Mitogen Activated Protein (MAP) kinases.

Effects of Cyclic RGD Peptide Functionalization on the Quantitative Bone Ingrowth Process in Cellularized Biphasic Calcium Phosphate Ceramics

The aim of this study was to evaluate the in vivo effects of the grafting of cyclo- DfKRG on the early phase of integration of biomaterials made with macroporous hydroxyapatite/b-tricalcium phosphate colonized with autologous bone marrow stromal cells. Non-grafted (-RGD) and grafted (+RGD) biomaterials were implanted in both femoral condyles of rabbits for 2 and 4 weeks. Two weeks after implantation, the global bone formation was higher with +RGD samples (p=0.02). There remained no significant difference 4 weeks after implantation. In conclusion, grafting of cyclo-DfKRG peptide on materials could promote cell colonization and improve osteoconduction during the first stage of the bone cicatrization process.