Figure 1.

Addition of vitamin C results in increased frequency of allo-iTregs with higher Foxp3 expression levels. (A) Isolated sp-DCs from BALB/c mice were co-cultured with allogeneic CD4⁺Foxp3^RFP− peripheral T cells isolated from Foxp3^RFP reporter mice (C57BL/6) in presence of IL-2, TGF-β, and retinoic acid (RA) for 6 days. In part of the cultures, vitamin C was added. On day 6, expression of Foxp3 was analyzed by flow cytometry. Numbers indicate frequency of Foxp3⁺ cells. Representative data from one out of twelve independent experiments are depicted. (B) Graph shows frequency of Foxp3⁺ allo-iTregs from cultures ± vitamin C. Data are summarized from twelve independent experiments (mean ± SD) and tested for significance using Mann–Whitney test; *p < 0.05. (C) Graph shows fold change (FC) of mean fluorescent intensity (MFI) of Foxp3 expression between vitamin C-treated and non-treated allo-iTregs; lines connect data generated in the same experiment.