Figure 8.

Extensive cell binding to DRT, a biomaterial rich in adhesion ligands, is observed in biomaterial-induced regeneration, both in skin and peripheral nerves. A: In the case of a scaffold with very large pores (e.g., average pore size 400 μm, which does not induce regeneration), the low specific surface (surface per volume) of the material reduces the amount of adhesion ligands available per cell. In this case MFB bind to other MFB, forming large capsules inside the pores of the biomaterial rather than adhering to its surface. B: In the case of DRT (pore size approximately 100 μm, which induces regeneration), the mean pore diameter corresponds to a large specific surface and extensive cell-scaffold adhesion. MFB form few cell-cell contacts and do not form large capsules. C: The chemical stimuli provided by an active biomaterial to interacting cells depend both on the specific surface (SEM image shows the structure of a collagen scaffold of 90 μm mean pore diameter) and the surface chemistry of the scaffold (depicted in the insert as density of ligands of particular adhesion receptors, e.g. the GFOGER ligand for collagen-binding integrins). D: Illustration of a MFB interacting with the DRT surface. The extensive binding of each MFB on the DRT surface is mediated by binding of MFB adhesion receptors on the ligand-rich scaffold surface. For example, the insert depicts the binding of the I domain of integrin α₂ on the GFOGER ligand present in collagen molecules (rendering based on the crystal structure 1DZI).