The role of macrophage subsets in and around the heart in modulating cardiac homeostasis and pathophysiology

Abstract

Cardiac and pericardial macrophages contribute to both homeostatic and pathophysiological processes. Recent advances have identified a vast repertoire of these macrophage populations in and around the heart - broadly categorized into a CCR2+/CCR2- dichotomy. While these unique populations can be further distinguished by origin, localization, and other cell surface markers, further exploration into the role of cardiac and pericardial macrophage subpopulations in disease contributes an additional layer of complexity. As such, novel transgenic models and exogenous targeting techniques have been employed to evaluate these macrophages. In this review, we highlight known cardiac and pericardial macrophage populations, their functions, and the experimental tools used to bolster our knowledge of these cells in the cardiac context.

Heart-on-a-chip systems: disease modeling and drug screening applications

“…1 An anatomical schematic of the heart and heart wall with the main constituent cell types in each layer. [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] Cellular composition ranges are estimated from the literature. [38][39][40] ECs = endothelial cells, CMs = cardiomyocytes.…”

Cardiac fibrogenesis: an immuno-metabolic perspective

“…In the adult heart, monocyte-derived CCR2 + macrophages are recruited by the inflammatory signal transduction pathways, DAMPs, and other chemokine-driven pathways and replace the CCR2 - population ( Dewald et al, 2005 ; Frangogiannis et al, 2007 ). Upon recruitment, the CCR2 + population continues the phagocytic activities and promotes inflammation by activating the inflammatory bodies, by pattern recognition receptor (PRR) signaling, and by producing cytokines ( Epelman et al, 2014a ; Heidt et al, 2014 ; Sager et al, 2016 ; Bajpai et al, 2019 ; Chen et al, 2023 ; Isidoro and Deniset, 2023 ). These macrophages play a role in regulating inflammation, promoting fibrosis, facilitating matrix remodeling, supporting angiogenesis, and contributing to the process of regeneration.…”

Cardiac resident macrophages: Spatiotemporal distribution, development, physiological functions, and their translational potential on cardiac diseases

“…Several exogenous or genetic methods are used to study the macrophages 78 . From the perspective of in vivo studies, to verify specific macrophage function, clodronate liposomes are used to knock out or deplete macrophages 79 , 80 .…”