Interfacial Design of Glyco-nanolayers for Cell Adhesion

Abstract

Carbohydrate chains are the third biopolymer following nucleic acids and proteins. Cells are covered with chain-like carbohydrates derived from glycoproteins and glycolipids. Cellular signaling and regulation in biological systems occur on the boundary surfaces of cell membranes, called biointerfaces here, via carbohydrate-protein interactions. Therefore, structural and biofunctional design of carbohydrate-based scaffolds for cell culture applications has attracted much attention in tissue engineering and regenerative medicines. However, in most cases, such trials remain limited to utilize the physicochemical properties of polysaccharides such as porous gel structures and water uptake properties. In our works, various carbohydrate chains were site-selectively modified at their reducing ends with thiosemicarbazide, and successfully immobilized on a gold substrate through self-assembly chemisorption via S-Au bonding. Carbohydrate clusters with regulated orientation and surface density made significant contribution to cell adhesion, cellular signaling and alignment required for tissue engineering. Besides, the rigid nanofibrous form of surface-carboxylated cellulose nanofibers was promising to imitate the structures and functions of extracellular matrix in vivo from viewpoints of physics and chemistry. This article focuses on the in vitro carbohydrate-mediated bioresponses in cell culture systems, and reviews our recent advances in the functional nano-architectonics of glyco-biointerfaces to realize materials therapy.