Abstract

Engineering Free Standing 2D and 3D Biostructures by Induction of Self-Assembly Organization of Cells in a Suspension

Kennedy Okeyo, Senior Lecturer, Institute for Frontier Life and Medical Sciences, Kyoto University

Biomaterials such as cell sheets continue to attract attention due to their potential application in regenerative medicine and drug screening. The ability to fabricate free standing biomaterials with a desirable functionality or cell orientation will facilitate their application.  In this talk, we introduce a newly developed method for engineering monolayer cell sheets with controlled cell orientation that employs suspended microstructured mesh sheets with fine strands (< 5 µm in width) and considerably large open meshes (>100 µm in mesh size) as scaffolds to support and direct initial cell attachment and growth. We show that the minimization of cell-substrate interaction achieved by this method can trigger self-assembly driven formation of biostructures in a suspension state, a phenomenon we attribute to the strengthening of cell-cell contact that occurs as a compensation for the limited cell-substrate adhesion imposed. Furthermore, we demonstrate the versatility of the method in inducing differentiation specification of human iPS cells, resulting in morphogenesis of trophoblast-like cysts that are capable of secreting trophoblast specific hormones such as hCG hormone, and express specific markers such as CDX2. Overall, we demonstrate the application of MEMS technology to fabricate functional biostructures.