Immune Cell Infiltration Analysis Based on Bioinformatics Reveals Novel Biomarkers of Coronary Artery Disease

Tianwen He,1,2,* Muheremu Muhetaer,1,2,* Jiahe Wu,1,2 Jingjing Wan,1,2 Yushuang Hu,1,2 Tong Zhang,1,2 Yunxiang Wang,1,2 Qiongxin Wang,1,2 Huanhuan Cai,1,2 Zhibing Lu1,2 1Department of Cardiology, Zhongnan Hospital of Wuhan University, Wuhan, People’s Republic of China; 2Institute of Myocardial Injury and Repair, Wuhan University, Wuhan, People’s Republic of China*These authors contributed equally to this workCorrespondence: Zhibing Lu; Huanhuan Cai, Department of Cardiology, Zhongnan Hospital of Wuhan University, No. 169 Donghu Road, Wuchang District, Wuhan, 430071, People’s Republic of China, Email luzhibing222@163.com; caihuanhuan@whu.edu.cnBackground: Coronary artery disease (CAD) is a multifactorial immune disease, but research into the specific immune mechanism is still needed. The present study aimed to identify novel immune-related markers of CAD.Methods: Three CAD-related datasets (GSE12288, GSE98583, GSE113079) were downloaded from the Gene Expression Integrated Database. Gene ontology annotation, Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and weighted gene co-expression network analysis were performed on the common significantly differentially expressed genes (DEGs) of these three data sets, and the most relevant module genes for CAD obtained. The immune cell infiltration of module genes was evaluated with the CIBERSORT algorithm, and characteristic genes accompanied by their diagnostic effectiveness were screened by the machine-learning algorithm least absolute shrinkage and selection operator (LASSO) regression analysis. The expression levels of characteristic genes were evaluated in the peripheral blood mononuclear cells of CAD patients and healthy controls for verification.Results: A total of 204 upregulated and 339 downregulated DEGs were identified, which were mainly enriched in the following pathways: “Apoptosis”, “Th17 cell differentiation”, “Th1 and Th2 cell differentiation”, “Gl