Nonclassical monocytes in cardiovascular physiology and disease

Am J Physiol Cell Physiol. 2021 May 1;320(5):C761-C770. doi: 10.1152/ajpcell.00326.2020. Epub 2021 Feb 17.


Monocytes are a heterogeneous cell population of innate immune cells with distinct cell surface markers that help them in carrying out different functions. In humans, there are three well-characterized subsets, namely, classical (CD14++CD16-), intermediate (CD14++CD16+), and nonclassical (CD14+ CD16++) monocytes. There is an emerging focus on the not yet well explored nonclassical monocytes that maintain vascular integrity by slowly patrolling on the endothelium, reacting to inflammatory signals, and clearing cell debris. In this manner, they are not only crucial for vascular homeostasis but also play a vital role in wound healing and resolution of inflammation by linking innate to adaptive immune response. Although they have been shown to be protective, yet they are also associated with inflammatory disease progression. This short review will give an insight about the emerging role of nonclassical monocytes in vascular homeostasis, inflammation, and protection in the context of cardiovascular disease.

Keywords: atheroprotection; conversion; patrolling monocytes; vascular inflammation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adaptive Immunity*
  • Animals
  • Cardiovascular Diseases / immunology*
  • Cardiovascular Diseases / metabolism
  • Cardiovascular Diseases / pathology
  • Endothelial Cells / immunology*
  • Endothelial Cells / metabolism
  • Endothelial Cells / pathology
  • Endothelium, Vascular / immunology*
  • Endothelium, Vascular / metabolism
  • Endothelium, Vascular / pathology
  • Humans
  • Immunity, Innate*
  • Inflammation / immunology*
  • Inflammation / metabolism
  • Inflammation / pathology
  • Inflammation Mediators / metabolism
  • Monocytes / immunology*
  • Monocytes / metabolism
  • Monocytes / pathology
  • Phenotype
  • Signal Transduction


  • Inflammation Mediators