Downregulation of TIGIT Expression in FOXP3+Regulatory T Cells in Acute Coronary Syndrome

Abstract

Xinlin Xiong,1– 3 Zhenhua Luo,4,5 Haiyan Zhou,3 Zonggang Duan,1 Li Niu,3 Kai Zhang,1 Guangwei Huang,1 Wei Li1,3 1Clinical College, Guizhou Medical University, Guiyang City, Guizhou Province, People’s Republic of China; 2Department of Cardiology, Chengdu University Affiliated Hospital, Chengdu City, Sichuan Province, People’s Republic of China; 3Department of Cardiology, Guizhou Medical University Affiliated Hospital, Guiyang City, Guizhou Province, People’s Republic of China; 4NHC Key Laboratory of Pulmonary Immune-related Diseases, Guizhou Provincial People’s Hospital, Guiyang City, Guizhou Province, People’s Republic of China; 5Department of Central Lab, Guizhou Provincial People’s Hospital, Guiyang City, Guizhou Province, People’s Republic of ChinaCorrespondence: Wei Li, Email [email protected]: Little is currently known on the role of T-cell immunoglobulin and ITIM domain (TIGIT) expression in Foxp3+ regulatory T cells (TIGIT+Tregs) in acute coronary syndrome (ACS) patients. The aim of this study was to investigate the role and alterations of TIGIT+Tregs in ACS patients.Methods: We enrolled 117 subjects, including 61 ACS patients, 26 chronic coronary syndrome (CCS) patients, and 30 control subjects without coronary artery disease. The quantification of TIGIT+Tregs was determined by flow cytometry; serum interleukin-6 (IL-6) and transforming growth factor-β (TGF-β) were also measured.Results: TIGIT+Tregs expression was significantly lower in ACS patients compared with CCS and control patients (P 0.05). Logistic regression analysis revealed that TIGIT+Tregs levels are independent predictors of ACS (P< 0.01). Receiver-operating characteristic (ROC) curve analysis showed the expression levels of TIGIT+Tregs had a discriminative power for ACS (P< 0.01). IL-6 levels were increased (P< 0.01), while TGF-β was decreased in ACS patients compared with CCS and control patients (P< 0.01). Meanwhile, an inverse correlation between IL-6 and TIGIT+Tregs was observed (P< 0.01), while a positive correlation between TGF-β and TIGIT+Tregs was found (P< 0.05).Conclusion: TIGIT+Tregs levels are significantly reduced in ACS, accompanied by upregulated IL-6 and downregulated TGF-β expression. The downregulated TIGIT+Tregs are independent predictors of ACS. These findings suggest that TIGIT+Tregs may have an anti-inflammatory and protective effect on ACS, and its decreased expression may be associated with atherosclerotic plaque destabilization.Keywords: T-cell immunoglobulin and ITIM domain, regulatory T cell, acute coronary syndrome, inflammation

Keywords

• t-cell immunoglobulin and itim domain
• regulatory t cell
• acute coronary syndrome
• inflammation