TGF-Β Signaling Play A Critical Role in De Novo Generation of CD4+CD25+ CD127dim Cells from Naïve T Cells in Comparison with Exogenous Foxp3 Transduction

Background: T-regulatory cell (Treg) therapy represents the immunological peripheral tolerance in allogeneic transplanta-tion and autoimmune diseases. Treg can be derived from progenitor naïve CD4+ T cells through TGF-β treatment and/or ex-ogenous Foxp3 transduction, while they show plasticity toward TH17 phenotype in inflammatory condition. In this study, we determine the in-vitro stability of Treg phenotype and also sup-pressive activity both in TGF-β-dependent Treg differentiation and Treg differentiated with exogenous Foxp3 transduction.Materials and Methods: Tregs were made by TGF-B and Foxp3 transduction from naïve CD4+ T cells in a normal and inflammatory milieu during 10 days. The inflamed condi-tion presented by IL-6 and SR1555 small molecule was used to avoid trans-differentiation toward TH17. Treg phenotype (CD4+ CD25+ CD127dim) was determined by flow cytometry and CFSE was used to measure the suppressive activity. The concentration of IL-17, TGF-β, IL-10 and IFN-γ was deter-mined by ELISA.The yield of Treg differentiation in the presence of TGF-β was significantly higher than Foxp3-transduced group. In the pres-ence of IL-6 and SR1555, cultured TGF-β-dependent Tregs maintained stable phenotype and they have shown higher sup-pressive activity than Foxp3-transduced groups. We had an in-crease in suppression activity when adding 10μg/ml SR1555. Low suppressive activity was observed with loss of Treg phe-notype in the presence of IL-6 in Foxp3-transduced groups in comparison with TGF-β group in days 5.Conclusion: Our finding indicated that to de novo generation of Treg, TGF-β treatment is more applicable than exogenous Foxp3 transduction and TGF-β signaling is important to main-tain stability of Treg phenotype and its suppressive activity. Acknowledge: An encouragement grant has been awarded to this study from Royan Stem Cell Technology Company, Teh-ran, Iran.

کلیدواژه ها:

Treg Generation ، Naive T Cell into Treg ، Treg/Th17 Imbalance ، Treg Trans-Differentiation ، Treg Therapy