Single-cell RNA sequencing in donor and end-stage heart failure patients identifies NLRP3 as a therapeutic target for arrhythmogenic right ventricular cardiomyopathy

Abstract

Background Dilation may be the first right ventricular change and accelerates the progression of threatening ventricular tachyarrhythmias and heart failure for patients with arrhythmogenic right ventricular cardiomyopathy (ARVC), but the treatment for right ventricular dilation remains limited. Methods Single-cell RNA sequencing (scRNA-seq) of blood and biventricular myocardium from 8 study participants was performed, including 6 end-stage heart failure patients with ARVC and 2 normal controls. ScRNA-seq data was then deeply analyzed, including cluster annotation, cellular proportion calculation, and characterization of cellular developmental trajectories and interactions. An integrative analysis of our single-cell data and published genome-wide association study-based data provided insights into the cell-specific contributions to the cardiac arrhythmia phenotype of ARVC. Desmoglein 2 (Dsg2)mut/mut mice were used as the ARVC model to verify the therapeutic effects of pharmacological intervention on identified cellular cluster. Results Right ventricle of ARVC was enriched of CCL3+ proinflammatory macrophages and TNMD+ fibroblasts. Fibroblasts were preferentially affected in ARVC and perturbations associated with ARVC overlap with those reside in genetic variants associated with cardiac arrhythmia. Proinflammatory macrophages strongly interact with fibroblast. Pharmacological inhibition of Nod-like receptor protein 3 (NLRP3), a transcriptional factor predominantly expressed by the CCL3+ proinflammatory macrophages and several other myeloid subclusters, could significantly alleviate right ventricular dilation and dysfunction in Dsg2mut/mut mice (an ARVC mouse model). Conclusions This study provided a comprehensive analysis of the lineage-specific changes in the blood and myocardium from ARVC patients at a single-cell resolution. Pharmacological inhibition of NLRP3 could prevent right ventricular dilation and dysfunction of mice with ARVC.

Animal Models and Molecular Pathogenesis of Arrhythmogenic Cardiomyopathy Associated with Pathogenic Variants in Intercalated Disc Genes

“…Fu and colleagues took advantage of the same murine model to test a different pharmacological intervention aimed at reducing proinflammatory macrophages [ 63 ]. Starting from single-cell RNA sequencing of myocardial samples from ACM patients, the authors highlighted an enrichment of pro-inflammatory macrophages characterized by the expression of Nod-like receptor protein 3 (NLRP3), which was suggested to play a role in the inflammatory response and was proposed as a possible target.…”

“…Consequently, Dsg2 mut/mut mice were treated over a 4 week period with either MCC950, a compound shown to inhibit NLRP3 activation, or PBS. Impaired ventricular function, increased cardiac fibrosis, and accumulation of pro-inflammatory macrophages became evident in the PBS-infused group, while these changes were alleviated in MCC950-treated mice [ 63 ]. Taken together, these results raised the possibility that targeting immune signaling could represent a novel approach for ACM therapy.…”