Imaging Immunometabolism in Atherosclerosis.

Over the past decade, there has been a growing recognition of the links between intracellular metabolism and immune cell activation, that is, immunometabolism, and its consequences in atherogenesis. However, most immunometabolic investigations have been conducted in cultured cells through pharmacologic or genetic manipulations of selected immunologic or metabolic pathways, limiting their extrapolation to the complex microenvironment of plaques. In vivo metabolic imaging is ideally situated to address this gap and to determine the clinical implications of immunometabolic alterations for diagnosis and management of patients. Indeed, 18F-FDG has been widely used in clinical studies with promising results for risk stratification of atherosclerosis and monitoring the response to therapeutic interventions, though the biologic basis of its uptake in plaques has been evolving. Herein, we describe recent advances in understanding of immunometabolism of atherosclerosis with an emphasis on macrophages, and we review promising metabolic imaging approaches using 18F-FDG and other PET radiotracers.