The extracellular matrix as a target for biophysical and molecular magnetic resonance imaging

Abstract

All tissues and organs are composed of cells and extracellular matrix (ECM). The components of the ECM have important functional and structural roles in tissues. On the one hand, the ECM often dominates the biomechanical properties of soft tissues and provides mechanical support to the tissue. On the other hand, ECM components maintain tissue homeostasis, pH, and hydration of the micromilieu and, via signal transduction, also play a key role in ECM-cell interactions which in turn control cell migration, differentiation, growth, and death. Inflammation, fibrosis, tumor invasion, and injury are associated with the transition of the ECM from homeostasis to remodeling which can dramatically alter the biochemical and biomechanical properties of ECM components. Hence, it is possible to detect and characterize disease by sensing biochemical and biomechanical changes of the ECM when appropriate imaging methods are used. This chapter discusses ECM-specific magnetic resonance imaging (MRI) based on contrast agents and elastography from a clinical radiological perspective in a variety of diseases including atherosclerosis, cardiomyopathy, inflammation, and liver fibrosis.