Silk-based 3D biotextiles support human adipose derived stem cells towards osteogenic differentiation

Textile-based technologies are considered as potential routes for TE applications, since they allow for producing finely tuned fibre-based porous scaffolds with a very reproducible and interconnected intra-architectural geometry, increasing the surface area for cell attachment and tissue ingrowth. Human Adipose-derived Stem Cells (hASCs) con-stitute an emerging possibility for regenerative medicine and tissuereplacement therapies. Their osteogenic differentiation potential, easyisolation, expansion andin vitroproliferation demonstrate their promis-ing prospects in bone regeneration. The present work aims at evaluat-ing the potential of recently developed 3D silk-based biotextilestructures to support hASCs adhesion, proliferation and osteogenic dif-ferentiation. The 3D spacer structures were processed by using a knit-ting technology. Two knitted silk layers were assembled and spaced byamonofilament of polyethylene terephthalate (PET). A 3D structuremade entirely of PET was also used for comparative purposes. Cellswere seeded over the constructs for 7, 14, 21 and 28 days in basal andosteogenic conditions. HASCs adhesion, proliferation and the osteo-genic differentiation potential of the textile structures were analysedthrough Scanning Electron Microscopy (SEM) and preliminary biologi-cal assays: alkaline phosphatase (ALP), DNA and Ca2+quantification.The obtained results validate the developed constructs as suitable forhASCs adhesion, proliferation and differentiation into an osteoblasticlineage. Great evidences of extracellular matrix mineralization wereobserved as well as a deeply cell penetration and colonization into thescaffolds interior. The positive influence of the producedfibre-basearchitecture on the osteogenic differentiation of hASCs and ECM pro-duction validates thistechnology for being used in bone TE. Moreover,the versatility and reproducibility of this knitting technology can allowfor further industrialization of TE products.