Epigenetically Mediated Pathogenic Effects of Phenanthrene on Regulatory T Cells
Figure 1
Phenanthrene exposure increases CpG methylation and reduces FOXP3 expression in primary Treg. Purified CD4+CD25hiCD127lo FOXP3+ Treg from PBMC of healthy donors () were incubated with 300 nM Phe (black), TCDD (blue), FICZ (red), or diluent (grey) for 0 to 7 days. (a) Quantification of methylated CpG sites (out of 13 total promotor and intronic sites) within the FOXP3 locus over the 7-day culture. (b) After a 2-day incubation with Phe, DNA was analyzed for percentage of methylated CpG sites within promoter (black square, ) and intronic (gray triangle, ) sequences of the FOXP3 locus. (c) FOXP3 transcripts were quantified with QT-PCR and normalized to the housekeeping gene β-glucuronidase. (d) Linear regression analysis of FOXP3 transcript expression to the number of methylated CpG sites within the FOXP3 locus; = Spearman’s correlation coefficient. (e) Intracellular FOXP3 protein expression was measured by flow cytometry and reported as median fluorescence intensity (MFI). ; error bars represent SD.
