A facile technique is herein reported to fabricate three-dimensional （3D） polymeric porous scaffolds with interior surfaces of a topographic microstructure favorable for cell adhesion. As demonstration, a well-known...A facile technique is herein reported to fabricate three-dimensional （3D） polymeric porous scaffolds with interior surfaces of a topographic microstructure favorable for cell adhesion. As demonstration, a well-known biodegradable polymer poly（lactide-co-glycolide） （PLGA） was employed as matrix. Under the porogen-leaching strategy, the large and soft porogens of paraffin were modified by colliding with small and hard salt particles, which generated micropits on the surfaces of paraffin spheres. The eventual PLGA scaffolds after leaching the modified porogens had thus interior surfaces of microscale roughness imprinted by those micropits. The microrough scaffolds were confirmed to benefit adhesion of bone marrow stromal cells （BMSCs） of rats and meanwhile not to hamper the proliferation and osteogenic differentiation of the cells. The insight and technique might be helpful for biomaterial designing in tissue engineering and regenerative medicine.展开更多
Cell adhesion to extracellular matrices(ECM)is critical to physiological and pathological processes as well as biomedical and biotechnological applications.It has been known that a cell can adhere on an adhesive micro...Cell adhesion to extracellular matrices(ECM)is critical to physiological and pathological processes as well as biomedical and biotechnological applications.It has been known that a cell can adhere on an adhesive microisland only over a critical size.But no publication has concerned critical adhesion areas of cells on microislands with nanoarray decoration.Herein,we fabricated a series of micro-nanopatterns with different microisland sizes and arginine-glycine-aspartate(RGD)nanospacings on a nonfouling poly(ethylene glycol)background.Besides reproducing that nanospacing of RGD,a ligand of its receptor integrin(a membrane protein),significantly influences specific cell adhesion on bioactive nanoarrays,we confirmed that the concept of critical adhesion area originally suggested in studies of cells on micropatterns was justified also on the micro-nanopatterns,yet the latter exhibited more characteristic behaviors of cell adhesion.We found increased critical adhesion areas of human mesenchymal stem cells(hMSCs)on nanoarrayed microislands with increased RGD nanospacings.However,the numbers of nanodots with respect to the critical adhesion areas were not a constant.A unified interpretation was then put forward after combining nonspecific background adhesion and specific cell adhesion.We further carried out the asymptotic analysis of a series of micro-nanopatterned surfaces to obtain the effective RGD nanospacing on unpatterned free surfaces with densely grafted RGD,which could be estimated nonzero but has never been revealed previously without the assistance of the micro-nanopatterning techniques and the corresponding analysis.展开更多
基金financially supported by Chinese Ministry of Science and Technology(973 programs Nos.2009CB930000 and 2011CB606203)NSF of China(Nos.21034002,91127028 and 51273046)
文摘A facile technique is herein reported to fabricate three-dimensional （3D） polymeric porous scaffolds with interior surfaces of a topographic microstructure favorable for cell adhesion. As demonstration, a well-known biodegradable polymer poly（lactide-co-glycolide） （PLGA） was employed as matrix. Under the porogen-leaching strategy, the large and soft porogens of paraffin were modified by colliding with small and hard salt particles, which generated micropits on the surfaces of paraffin spheres. The eventual PLGA scaffolds after leaching the modified porogens had thus interior surfaces of microscale roughness imprinted by those micropits. The microrough scaffolds were confirmed to benefit adhesion of bone marrow stromal cells （BMSCs） of rats and meanwhile not to hamper the proliferation and osteogenic differentiation of the cells. The insight and technique might be helpful for biomaterial designing in tissue engineering and regenerative medicine.
基金supported by the National Key R&D Program of China(No.2016YFC1100300)he National Natural Science Foundation of China(Nos.21961160721 and 21704018).
文摘Cell adhesion to extracellular matrices(ECM)is critical to physiological and pathological processes as well as biomedical and biotechnological applications.It has been known that a cell can adhere on an adhesive microisland only over a critical size.But no publication has concerned critical adhesion areas of cells on microislands with nanoarray decoration.Herein,we fabricated a series of micro-nanopatterns with different microisland sizes and arginine-glycine-aspartate(RGD)nanospacings on a nonfouling poly(ethylene glycol)background.Besides reproducing that nanospacing of RGD,a ligand of its receptor integrin(a membrane protein),significantly influences specific cell adhesion on bioactive nanoarrays,we confirmed that the concept of critical adhesion area originally suggested in studies of cells on micropatterns was justified also on the micro-nanopatterns,yet the latter exhibited more characteristic behaviors of cell adhesion.We found increased critical adhesion areas of human mesenchymal stem cells(hMSCs)on nanoarrayed microislands with increased RGD nanospacings.However,the numbers of nanodots with respect to the critical adhesion areas were not a constant.A unified interpretation was then put forward after combining nonspecific background adhesion and specific cell adhesion.We further carried out the asymptotic analysis of a series of micro-nanopatterned surfaces to obtain the effective RGD nanospacing on unpatterned free surfaces with densely grafted RGD,which could be estimated nonzero but has never been revealed previously without the assistance of the micro-nanopatterning techniques and the corresponding analysis.
