Macrophage specific delivery of photosensitizer and light activation reduce inflammation and burden of atherosclerotic plaque via activation of autophagy and efferocytosis of apoptotic cells

Photoactivation is a promising theranostic tool to image and stabilize the atherosclerotic plaque by apoptosis induction in macrophages or other vascular cells; however, lack of effective drugs and mechanistic understanding hinder its clinical application for cardiovascular disease. Here, we developed the macrophage targeted photosensitizer delivery strategy and demonstrated that imaging assisted light activation reduced inflammation and burden of atherosclerotic plaques. Mechanistically, targeted photoactivation induced autophagy and increased MerTK expression in carotid atheroma as early as 1 day, and had 2-fold increase in macrophage-associated apoptotic cells, indicating efferocytosis enhancement. This multifunctional photoactivatable theranostic strategy could confer a promising tool for high-risk plaques.