Figure 1.

Canonical M1 and M2 polarization of Macs. Under a range of polarization signals, naïve Macs are polarized toward M1-like (LPS, IFN-γ skews) or M2-like (IL-4, IL-13 skews) Macs. There are several surfaces, intracellular or intranuclear markers for the detection of Mac phenotypes. Other than recognition markers, some specific pathways are upregulated or downregulated in M1 and M2 Macs. For example, glycolysis, pentose phosphate pathway, and fatty acid synthesis are upregulated in M1 Macs, while oxidative phosphorylation and β-oxidation pathways are upregulated in M2 Macs.