| BACKGROUND:A thorough study of the risk factors and pathogenesis of cardiovascular disease plays an extremely important role in preventing the occurrence of disease,delaying the progress of disease,improving the prognosis of patients,and improving the quality of life.Coronary heart disease and valvular heart disease are two common cardiovascular diseases.As a variety of cell types are involved and/or dysfunctional,a completely effective treatment strategy has not been developed.Attributing the progression of the lesion to a specific cell type is challenging,because of the high heterogeneity of cells not only within but also around the lesion.Therefore,it is urgent to distinguish the heterogeneity of coronary artery perivascular adipose tissue(PVAT)and cardiac valve cells at the single cell level to discover important pathogenic subpopulations.METHODS:We performed single-cell RNA sequencing(scRNA-seq)of the stromal vascular fraction of coronary PVAT from three groups of heart transplant recipients,including three patients with advanced atherosclerosis,three patients with early atherosclerosis,and four non-atherosclerosis control subjects.The cellular landscapes of non-diseased human cardiac valve leaflets(five aortic valves,five pulmonary valves,five tricuspid valves,and three mitral valves)from end-stage heart failure patients undergoing heart transplantation were explored.Bioinformatics was used to annotate the cellular populations,depict the cellular developmental trajectories and interactions,and explore the differences among three groups of coronary PVAT as well as four types of heart valves at the cellular and molecular levels Pathological staining,quantitative real-time polymerase chain reaction,and in vitro studies were performed to validate the key findings in coronary PVAT.The comprehensive analysis of single cell data and published data based on genome-wide association research and bulk RNA sequencing provides important insights into the cell specific contribution of calcified aortic valve disease.RESULTS:On the one hand,10 cell types were identified among 70,447 cells from human coronary PVAT.Several cellular subpopulations,including SPP1+ macrophages,and profibrotic preadipocytes,were accumulated in PVAT surrounding atherosclerotic coronary arteries compared to non-atherosclerosis coronary arteries.The fibrosis percentage was increased in PVAT surrounding atherosclerotic coronary arteries and it was positively associated with the grade of coronary artery stenosis.Cellular interaction analysis suggested osteopontin(OPN)secreted by SPP1+macrophages interacted with CD44/integrin on fibro-adipogenic progenitor cells.Strikingly,correlation analyses uncovered that higher level of SPP1 in PVAT correlate with a more severe fibrosis degree and a higher coronary stenosis grade.In vitro studies showed that OPN promoted migration and proliferation of fibro-adipogenic progenitor cells,which can be blockade by anti-CD44 or an integrin inhibitor.On the other hand,six cell types were identified among 128,412 cells from non-diseased human cardiac valve leaflets.Valvular interstitial cells were the largest population,followed by myeloid cells,lymphocytes,valvular endothelial cells,mast cells,and myofibroblasts.The four types of cardiac valve had distinct cellular compositions.The intercellular communication analysis revealed that valvular interstitial cells were at the center of the communication network.The integrative analysis of our scRNA-seq data revealed key cellular subpopulations involved in the pathogenesis of valvular heart diseases.CONCLUSIONS:1.SPP1+ macrophages were enriched in the PVAT of atherosclerotic coronary arteries,which may be involved in the progression of coronary atherosclerosis.2.The cellular landscape differed among the four types of non-diseased cardiac valve,which might explain their differences in susceptibility to pathological remodeling and valvular heart disease. |
PDF Full Text Request