Pathophysiological relevance of macrophage subsets in atherogenesis

Luca Liberale; Franco Dallegri; Fabrizio Montecucco; Federico Carbone

doi:10.1160/TH16-08-0593

Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2017; 117(01): 07-18
DOI: 10.1160/TH16-08-0593

Review Article

Schattauer GmbH

Pathophysiological relevance of macrophage subsets in atherogenesis

Authors

Luca Liberale

¹First Clinic of Internal Medicine Department of Internal Medicine, University of Genoa, Genoa, Italy
Franco Dallegri

¹First Clinic of Internal Medicine Department of Internal Medicine, University of Genoa, Genoa, Italy

²First Clinic of Internal Medicine, IRCCS AOU San Martino–IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
Fabrizio Montecucco

¹First Clinic of Internal Medicine Department of Internal Medicine, University of Genoa, Genoa, Italy

²First Clinic of Internal Medicine, IRCCS AOU San Martino–IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy

³Centre of Excellence for Biomedical Research (CEBR), University of Genoa, Genoa, Italy
Federico Carbone

¹First Clinic of Internal Medicine Department of Internal Medicine, University of Genoa, Genoa, Italy

Abstract

Summary

Macrophages are highly heterogeneous and plastic cells. They were shown to play a critical role in all stages of atherogenesis, from the initiation to the necrotic core formation and plaque rupture. Lesional macrophages primarily derive from blood monocyte, but local macrophage proliferation as well as differentiation from smooth muscle cells have also been described. Within atherosclerotic plaques, macrophages rapidly respond to changes in the microenvironment, shifting between pro- (M1) or anti-inflammatory (M2) functional phenotypes. Furthermore, different stimuli have been associated with differentiation of newly discovered M2 subtypes: IL-4/IL-13 (M2a), immunecomplex (M2b), IL-10/glucocorticoids (M2c), and adenosine receptor agonist (M2d). More recently, additional intraplaque macrophage phenotypes were also recognized in response to CXCL4 (M4), oxidized phospholipids (Mox), haemoglobin/haptoglobin complexes (HAmac/M(Hb)), and heme (Mhem). Such macrophage polarization was described as a progression among multiple phenotypes, which reflect the activity of different transcriptional factors and the cross-talk between intracellular signalling. Finally, the distribution of macrophage subsets within different plaque areas was markedly associated with cardiovascular (CV) vulnerability. The aim of this review is to update the current knowledge on the role of macrophage subsets in atherogenesis. In addition, the molecular mechanisms underlying macrophage phenotypic shift will be summarised and discussed. Finally, the role of intraplaque macrophages as predictors of CV events and the therapeutic potential of these cells will be discussed.

Keywords

Monocyte - macrophage - polarisation - atherosclerosis

Full Text

References

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