After TCDD-treated DCs were cocultured with naïve CD4+ T cells, the mRNA expression levels of IFN-γ (1.33 ± 0.24), T-bet (2.72 ± 0.33), IL-17 (1.92 ± 0.12), and RORγt (1.19 ± 0.20) were higher in the PBC DC+PBC T cell group than in the HC DC+HC T cell group (0.59 ± 0.08, 0.89 ± 0.24, 0.84 ± 0.18, and 0.68 ± 0.07; p < 0.01, p < 0.01, p < 0.05, and p < 0.05, respectively). The gene discussed is IFNG; the disease is primary biliary cholangitis.