Isolation and differentiation of human macrophages

Macrophage subtypes display protective or pathogenic activities in vascular lesions. They recognize and engulf modified lipids, accumulate in the arterial intima, contributing to the atherosclerosis development. In the heart, vascular tissues and perivascular adipose tissues, there is increasing evidence that macrophages play a role in endothelial dysfunction, vascular inflammation and remodeling. In this chapter we describe protocols to isolate human monocytes from peripheral blood mononuclear cell and how to differentiate them into macrophages by using growth factors (granulocyte-macrophage colony-stimulating factor—GM-CSF or colony-stimulating factor—M-CSF) or by different cell culture medium concentration. We also describe how to identify different macrophage activation phenotypes.