Tissue Engineering: Nanoscale Contacts in Cell Adhesion to Substrates

Abstract

Tissue engineering is the exploitation of a combination of cells, engineered materials, and suitable biochemical and mechanical factors and processes to improve or replace biological functions. A number of questions in tissue engineering involve cell dynamics and proliferation. Motility is the hallmark of life, and mechanical forces—foremost adhesion and friction forces— play a fundamental role in cell migration, cell positioning, and cell-to-cell binding and tissue stabilization when contractile forces are generated within the cell and pull the cell body forward. In living systems such as cells, force interactions are more complex than those of the inorganic world because living systems continuously adapt the forces required for their movements by processing a number of internal and external signals and by converting different forms of energy into mechanical energy. Animal cells have an average size of 10–40 μm, but the adhesion with substrates is limited to sites whose dimensions fall in the nanometer range. As a consequence, a basic understanding on the nanoscale level is needed to have satisfactory knowledge of cell frictional and adhesion fundamental properties. Different techniques has been used to measure or to investigate how living cells adhere to other cells, to the extracellular matrix, or biocompatible scaffolds in their native environment.With the advent of the scanning probe microscopy family, it has been made possible both to study adhesive fundamental properties and features simulating the interaction between living systems, and to shed light on some processes occurring in complex living matter on the nanoscale making use of the atomic force microscopy based technique. This chapter describes summarily the role of the adhesion mechanisms occurring in cell dynamics and discusses some experimental results for adhesion forces between cells and scaffolding substrates on which they spread and proliferate.