Biomechanical Properties of Fibroblasts

Abstract

Cells are a complex topic of study for materials scientists. They are the fundamental building blocks of living organisms, able to sense their environment and act in response to it. In addition to their many biochemical functions, cells also play a mechanical role: They hold organs in place and move to the locations where they are needed in processes like wound healing, metastasis, or embryogenesis. Their mechanical behavior is mostly determined by a meshwork of three types of connected biopolymers (actin microfilaments, microtubules, and intermediate filaments) that compose a structural framework called the cytoskeleton, surrounded by a lipid membrane (Figure 1). In contrast to this simple picture, cells are very different from polymer gels or liposomes: They are active materials, powered by chemically stored energy. Their mechanical condition is closely linked to their biochemical function; for example, they may “commit suicide,” following a well-defined protocol known as apoptosis, which can be triggered by their mechanical state.The enormous progress of modern cell biology combined with new micromanipulation techniques is leading researchers toward a more global understanding of the mechanical properties of cells and toward finding a functional link between biochemistry, chemical signaling, and cell mechanics, thus crossing the boundaries between these subjects.The characterization of cell mechanical behavior has been the object of numerous studies. Red blood cells are a simple model system; if deprived of a nucleus while retaining a constant surface area, they have properties reminiscent of lipid vesicles.