ABSTRACT
Objective To investigate the phenotypic and functional properties of in vitro-induced He-lios+regulatory T cells(Helios+iTreg) and to analyze the differences between Helios+iTreg and Helios+thymic-derived natural Treg (Helios+nTreg). Methods CD4+CD25- effector T cells (CD4+CD25- Teff) that were separated from healthy subjects were cultured with anti-CD3 and anti-CD28 antibodies and stimulated with IL-2 and TGF-β to induce the generation of Helios+iTreg. Flow cytometry and real-time PCR were respectively used to analyze the differences in phenotype and CpG methylation in Treg-specific demethylated region (TSDR) be-tween Helios+iTreg and Helios+nTreg derived from the same donor. Results CD45RA was highly expressed on Helios+iTreg, but not on Helios+nTreg. Additionally, Helios+iTreg expressed significantly higher levels of CD127,ICOS and PD-1,but lower levels of CXCR3,CCR4 and CD25 than Helios+nTreg did. IFN-γ and IL-2 that expressed by Helios+iTreg were more than those by Helios+nTreg. It was also found that the level of CpG methylation in TSDR was much higher in Helios+iTreg than in Helios+nTreg. Conclusion Both nTreg and iTreg expressed Helios,but the phenotypic and functional properties of the two Treg subsets were different. It was suggested that Helios+iTreg and Helios+nTreg might play different roles in the immune system.