Figure 5.

Tolerogenic dendritic cells (tolDCs) suppress mature DC (matDC)-induced T cell proliferation, interferon (IFN)γ and interleukin (IL)-17. (A) Representative graph showing control CD4 T cell responses to purified protein derivative (PPD)-loaded DCs (1 µg/ml). CD4 T cells (10⁵) were cocultured at a 10:1 ratio with tolDCs or matDCs alone or matDCs with an equivalent number of tolDCs or matDCs as a cell number control (1:1 ratio; 10⁴) or 10-fold fewer tolDCs than matDCs (1:10 ratio; 10³). Proliferation was quantitated at days 3, 5 and 7 by [³H]thymidine incorporation. The graph is representative of four independent experiments. (B) Mean IFNγ and IL-17 cytokine production relative to matDCs. CD4 T cells (10⁵) were stimulated with autologous PPD-loaded DCs as in (A). Cytokine production was quantitated on day 6 by ELISA. Data are expressed as the mean±SEM from three independent experiments. *p≤0.05, **p≤0.01, ***p≤0.001 as compared with matDCs (two-way analysis of variance (A) and analysis of variance (B)).