The spatial patterning of RGD and BMP-2 mimetic peptides at the subcellular scale modulates human mesenchymal stem cells osteogenesis
Résumé
Engineering artificial extracellular matrices, based on the biomimicry of the spatial distribution of proteins and growth factors within their native microenvironment, is of great importance for understanding mechanisms of bone tissue regeneration. Herein, photolithography is used to decorate glass surfaces with subcellular patterns of RGD and BMP-2 ligands; two mimetic peptides recognized to be involved in stem cells osteogenesis. The biological relevance of well-defined RGD and BMP-2 patterned surfaces is evaluated by investigating the differentiation of human mesenchymal stem cells (hMSCs) into osteoblasts, in the absence of induction media. The extent of hMSCs differentiation is revealed to be dependent on both the pattern shape and the ligand type. Indeed, the spatial patterning of BMP-2, but not RGD peptide, significantly enhances the extent of hMSCs differentiation, suggesting that geometric cues guide stem cells specification into specialized cells in a ligand type dependent manner. Such cell culture models provide an interesting tool to investigate how stem cells perceive and respond to their microenvironment and may contribute to the development of next-generation biomaterials capable of producing clinically relevant volume of bone tissue.