| Objective: The numbers and suppressive function of CD4~+CD25~+FOXP3~+ regulatory T cells (Treg) are impaired in patients with acute coronary syndromes (ACS). However, the mechanism underlying this phenomenon is unknown. Therefore, the aim of this study was to investigate whether recent thymic emigrants (RTE) Treg (RTE-Treg) contribute to the reduction of number and suppressive deficiency in Treg.Methods: 77 Subjects were divided into three groups: acute coronary syndromes (ACS, n=28), stable angina pectoris (SA, n=25) and healthy controls (HCs, n=24). Peripheral blood mononuclear cells (PBMC) were isolated by density gradient centrifugation. We determined that express CD31~+ combined CD45RA~+ as recent thymic emigrant typical surface marker. The frequencies of CD31~+CD45RA~+CD4~+CD25~+FOXP3~+ Regulatory T Cells (Treg) in peripheral blood were detected by flow cytometry. Meanwhile, we assess number of T-cell receptor excision circles (TREC) in Treg by real-time quantitative PCR to further investigate recent thymic emigrants CD25~+FOXP3~+Regulatory T Cells in patients with ACS. Results: Frequencies of CD31~+CD45RA~+ Treg are reduced in the peripheral blood of ACS patients (ACS vs SA, P=0.003 and ACS vs HCs P<0.001). TREC numbers in Treg are reduced in the peripheral blood of ACS patients (ACS vs SA, P=0.001 and ACS vs HCs, P<0.001). Meanwhile, frequencies of CD31~+CD45RA~+ Treg and TREC numbers in Treg have a positive correlation(r=0.493, P=0.014).Conclusion: The results demonstrated that ACS patients revealed significantly decrease in peripheral recent thymic emigrants-Treg number, suggesting a potential role for reduced recent thymic emigrants-Treg in plaque destabilization and the onset of ACS. |
