Figure 2.

Macrophage subsets in the atherosclerotic lesion. M1 proinflammatory and M2 anti-inflammatory macrophages are polarized by Th1 and Th2 cytokines, respectively. Haem-induced phenotypes including M(Hb) and Mhem are M2-like and show anti-inflammatory effects such as resistant to lipid uptake and suppressing oxidative stress. Intermediate phenotypes Mox and M4 display reduced capacity for phagocytosis and are potentially proinflammatory by expressing proatherogenic markers. Abbreviations: CXCL4: C-X-C motif chemokine 4; GM-CSF: granulocyte macrophage colony-stimulating factor; IFN-γ: interferon-γ; IL: interleukin; IRF: interferon regulatory factor 5; PAMPs: pathogen-associated molecular complexes; STAT: signal transducer and activator of transcription; TNF: tumor necrosis factor.