Nonclassical Patrolling Monocyte Function in the Vasculature

Abstract

Nonclassical patrolling monocytes are characterized by their unique ability to actively patrol the vascular endothelium under homeostatic and inflammatory conditions. Patrolling monocyte subsets (CX3CR1highLy6C- in mouse and CX3CR1highCD14dimCD16+ in humans) are distinct from the classical monocyte subsets (CCR2highLy6C+ in mouse and CCR2highCD14+CD16- in humans) and exhibit unique functions in the vasculature and inflammatory disease. Patrolling monocytes function in several disease settings to remove damaged cells and debris from the vasculature and have been associated with wound healing and the resolution of inflammation in damaged tissues. This review highlights the unique functions of these patrolling monocytes in the vasculature and during inflammation.