Heterocellularity and Cellular Cross-Talk in the Cardiovascular System

Abstract

Cellular specialization and interactions with other cell types are the essence of complex multicellular life. The orchestrated function of different cell populations in the heart, in combination with a complex network of intercellular circuits of communication, is essential to maintain a healthy heart and its disruption gives rise to pathological conditions. Over the past few years, the development of new biological research tools has facilitated more accurate identification of the cardiac cell populations and their specific roles. This review aims to provide an overview on the significance and contributions of the various cellular components: cardiomyocytes, fibroblasts, endothelial cells, vascular smooth muscle cells, pericytes, and inflammatory cells. It also aims to describe their role in cardiac development, physiology and pathology with a particular focus on the importance of heterocellularity and cellular interaction between these different cell types.

Keywords: cardiac fi broblast; cardiac tissue; endothelial cells (ECs); inflammatory cell; macrophages (M1/M2); multicellularity; myocytes; pericytes and vascular smooth muscle cells.

Figure 1

Cardiac multicellularity in vitro: Immunohistochemicalstaining and confocal microscopywere used to identify cardiac cells in a transverse section (A) and in a longitudinal section (B) of freshly prepared dog myocardial slices. Cardiomyocytes were labeled with caveolin 3, fibroblasts were labeled with vimentin and endothelial cells were labeled with isolectin. Nuclei were labeled with Hoechst 33342. Scale bar = 50 μm.

Figure 2

Immunohistochemical staining and confocal microscopy were used to identify endothelial cells distribution in a freshly prepared dog myocardial slice (A). Higher magnification of capillaries and their location in proximity to cardiomyocytes (B). Cardiomyocytes were labeled with caveolin 3 (red) and endothelial cells were labeled with isolectin (White and cyan).

Figure 3

Immunohistochemical staining and confocal microscopy were used to identify different cardiac populations in a dog myocardial slice. Large vessels were identified for α-Smooth Muscle Actin expression (white), endothelial cells were labeled with isolectin (green) and fibroblasts were labeled with vimentin (red) (A). Higher magnification of capillaries and their location in proximity to cardiomyocytes and fibroblasts (B). Cardiomyocytes were labeled with caveolin 3 (blue), endothelial cells were double labeled with isolectin (green) and Von Willerbrand factor (white) and fibroblasts for Vimentin (red).