Provided herein are compositions and methods for diagnosis and treatment of early-stage atherosclerotic plaques and reduction of plaques in arteries. In particular, provided herein are high-density-lipoprotein-functionalized magnetic nanostructures (HDL-MNS) capable of (i) precise anatomic detection of atherosclerotic lesions, (ii) removal of excess cholesterol from macrophage cells in atherosclerotic plaque, and/or (iii) delivery of therapeutic agents to plaque locations, and methods of diagnosis and treatment of atherosclerosis.
