Dissection of heterocellular cross-talk in vascularized cardiac tissue mimetics

Abstract

Cellular specialization and interaction with other cell types in cardiac tissue is essential for the coordinated function of cell populations in the heart. The complex interplay between cardiomyocytes, endothelial cells and fibroblasts is necessary for adaptation but can also lead to pathophysiological remodeling. To understand this complex interplay, we developed 3D vascularized cardiac tissue mimetics (CTM) to study heterocellular crosstalk in hypertrophic, hypoxic and fibrogenic environments. This 3D platform responds to physiologic and pathologic stressors and mimics the microenvironment of diseased tissue. In combination with endothelial cell fluorescence reporters, these cardiac tissue mimetics can be used to precisely visualize and quantify cellular and functional responses upon stress stimulation. Utilizing this platform, we demonstrate that stimulation of α/β-adrenergic receptors with phenylephrine (PE) promotes cardiomyocyte hypertrophy, metabolic maturation and vascularization of CTMs. Increased vascularization was promoted by conditioned medium of PE-stimulated cardiomyocytes and blocked by inhibiting VEGF or upon β-adrenergic receptor antagonist treatment, demonstrating cardiomyocyte-endothelial cross-talk. Pathophysiological stressors such as severe hypoxia reduced angiogenic sprouting and increased cell death, while TGF β2 stimulation increased collagen deposition concomitant to endothelial-to-mesenchymal transition. In sum, we have developed a cardiac 3D culture system that reflects native cardiac tissue function, metabolism and morphology-and for the first time enables the tracking and analysis of cardiac vascularization dynamics in physiology and pathology.

TGF-β-Induced Endothelial to Mesenchymal Transition in Disease and Tissue Engineering

“…In vitro 3D organ cultures can be used to study EndMTrelated diseases. For example, Wagner et al (2020) established 3D vascularized cardiac tissue mimetics (CTMs) by co-culturing cardiomyocytes (CM) and fibroblasts (FB) in spheroids and then complementing them with HUVECs to investigate the heterocellular crosstalk in different culture conditions. In this system, TGF-β stimulation could induce EndMT as vimentin/SM22α was expressed in Isolectin B4 stained ECs, and more vascularization was observed in CTMs.…”

SARS-CoV-2 infects and induces cytotoxic effects in human cardiomyocytes

“…Next, we determined if SARS-CoV-2 infects cardiomyocytes in a three dimensional tissue environment using human cardiospheres generated by hiPS-cells, which are generated by a 7 modified previously published protocol 12 (Figure 3a-b). SARS-CoV-2 time-dependently affected beating frequency of cardiospheres with a profound inhibition at 5 days post infection (Figure 3c).…”

Vascularisation of pluripotent stem cell–derived myocardium: biomechanical insights for physiological relevance in cardiac tissue engineering

“…While iPSC-CM have been shown to produce angiogenic extracellular vesicles, whether they can fully coordinate mature vessel formation as their native counterparts do, is yet to be shown. A recent neonatal rat ventricular (NRVM) model, based on hanging droplet “cardiac tissue mimetics” (CTM), is an example of a potential 3D in vitro platform to study iPSC-CM angio-/vasculogenic capacity [ 194 ] (Fig. 2a ).…”

“…2 In vitro models of myocardial-microvascular interaction. ( a ) Spheroid based static co-culture of cardiomyocytes (CM), fibroblast (FB), and human umbilical vein endothelial cells (HUVEC) [ 194 ]. ( b ) Co-differentiated human-induced pluripotent stem cell–derived cardiomyocytes (hiPSC-CM)-endothelial cell (EC) 3D microtissue (MT) [ 47 ].…”