Department of Cardiology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Hefei, 230001, China.
Graduate School, Wannan Medical College, Anhui Wuhu, 241002, China.
Int J Med Sci. 2024 Oct 14;21(14):2683-2693. doi: 10.7150/ijms.99518. eCollection 2024.
Alterations in circulating CCL4 levels have been implicated in coronary artery disease (CAD), but the causal relationship and underlying mechanisms remain unclear. This study aims to analyse the role of CCL4 and its receptor (CCR5) in CAD using Mendelian randomisation (MR) analysis, bulk RNA and single cell RNA sequencing (scRNA-seq). The MR analysis was used to determine the causal relationship between 91 circulating inflammatory proteins and CAD. Bulk RNA sequencing data was used to demonstrate the expression profile of CCL4/CCR5. The localisation of CCL4/CCR5 was determined using scRNA-seq data. Functional enrichment analyses were used to infer the potential role of CCL4 in CAD. Additional clinical samples were utilized to validate the results of MR. We identified six circulating inflammatory proteins associated with CAD. Of these, CCL4 was identified as a key inflammatory cytokine associated with CAD risk for MR analysis.The bulk RNA sequencing data from the Gene Expression Omnibus (GEO) datasets showed that CCR4 receptor(CCR5) expression was significantly higher in human atherosclerotic plaques compared to controls. Notably, scRNA-seq analysis revealed CCL4 was highly expressed in T cells, monocytes and macrophages. Clinical specimens confirmed high levels of serum CCL4 expression in CAD patients by ELISA.Functional enrichment analysis revealed that CCL4 was primarily enriched in the cytokines and cytokine receptors, viral proteins with cytokines and cytokine receptors, and chemokine signaling pathways. Our study presented a genetic insight into the pathogenetic role of CCL4-CCR5 in CAD, which may provide new insights for further mechanistic and clinical investigations of inflammatory cytokine-mediated CAD.
循环 CCL4 水平的改变与冠状动脉疾病（CAD）有关，但因果关系和潜在机制仍不清楚。本研究旨在通过孟德尔随机化（MR）分析、批量 RNA 和单细胞 RNA 测序（scRNA-seq）分析，研究 CCL4 及其受体（CCR5）在 CAD 中的作用。MR 分析用于确定 91 种循环炎症蛋白与 CAD 之间的因果关系。批量 RNA 测序数据用于展示 CCL4/CCR5 的表达谱。使用 scRNA-seq 数据确定 CCL4/CCR5 的定位。功能富集分析用于推断 CCL4 在 CAD 中的潜在作用。额外的临床样本用于验证 MR 的结果。我们确定了与 CAD 相关的六种循环炎症蛋白。其中，CCL4 被确定为与 CAD 风险相关的关键炎症细胞因子，用于 MR 分析。来自基因表达综合数据库（GEO）数据集的批量 RNA 测序数据显示，与对照组相比，人类动脉粥样硬化斑块中 CCR4 受体（CCR5）的表达显著更高。值得注意的是，scRNA-seq 分析显示 CCL4 在 T 细胞、单核细胞和巨噬细胞中高度表达。临床标本通过 ELISA 证实了 CAD 患者血清 CCL4 表达水平较高。功能富集分析显示，CCL4 主要富集在细胞因子和细胞因子受体、具有细胞因子和细胞因子受体的病毒蛋白以及趋化因子信号通路中。我们的研究提供了遗传角度对 CCL4-CCR5 在 CAD 中的发病机制作用的见解，这可能为进一步研究炎症细胞因子介导的 CAD 的机制和临床研究提供新的思路。
