Laminin-521 Promotes Rat Bone Marrow Mesenchymal Stem Cell Sheet Formation on Light-induced Cell Sheet Technology

The cell sheet technology is an area of research that is of great interest for tissue engineering and regenerative medicine. Here, the authors investigated the effects of an ECM coating on rat bone marrow mesenchymal stem cells (rBMSC) cultured on light-induced TiO2 nanodot films. Cell sheets can be detached on a TiO2 nanodot-coated quartz substrate by using UV365 illumination. The effects of rat fibronectin, human recombinant laminin-521, -511, -421, and -111 on the formation of cell sheets were investigated and also compared to uncoated films. The result showed the highest success for laminin-521. rBMSCs rapidly attached and spread on films coated with laminin-521 (1.2 ug/ml) and formed intact cell sheets after 5 days of culture. Laminin-521 promotes the formation of rBMSC sheets with good viability under hyperconfluent conditions (4 to 8 layers of cells). The cells also maintained multilineage potential, including osteogenic, adipogenic, and chondrogenic differentiation. The cell sheets formed had rich ECM (including collagen I) and cells were connected with each other in dense network-like tissue. rBMSC cultured on uncoated surface and cells partially detached and failed to form cell sheets. In summary, laminin-521 and UV365 illumination systems provided a simple, rapid, and effective cell sheets strategy.