Surface free energy-mediated cell sheet engineering using initiated chemical vapor deposition (iCVD)

Abstract

Tissue engineering has been developed for improving or replacing biological tissue by manipulating the cells in vitro. In the process of transplanting the cells cultured in vitro to the patient again, there are difficulties such that the foreign substance enters the body and causes an unexpected immune response or toxicity in the process of decomposition, and the enzyme reaction can damage cell surface proteins or extracellular matrix proteins. To solve these problems, the cell sheet engineering has been developed, in which cells are constructed themselves without scaffold. Currently, the most used material in cell sheet engineering is a temperature sensitive polymer called pNIPAAm, which uses phase shift of polymer with temperature change. However, in the process of detaching the sheet by lowering the temperature, the cells are exposed to a low temperature. In addition, it takes a long time to form the cell sheet. In this study, two types of monomers with different surface energies were blended to control the surface free energy and to form an intermediate cell attachment state. In this situation, the divalent cations in the culture solution were depleted, and then cell sheet could be fabricated by weakening ligand binding of adhesion proteins in cell surface. By controlling the adhesive force between the cells and the culture surface, the cell sheet could be formed in a short time without changing the temperature for various cell types. Through this study, it is expected to manufacture various tissue-customized cell sheets production.