diffDCs preferentially produce a high level of IL-10 but a low level of IL-12p70 and inhibit T-cell proliferation, ignoring TLR activation. (A) IL-10 and IL-12p70 production was measured by ELISA following stimulation of imDCs or diffDCs (1 × 10⁶ cells/mL) in 48-well plates with 500 ng/mL LPS, 1 μmol/mL CpG ODN, 5 ng/mL LTA, or 50 ng/mL HSP70 for 24 hours. Unstimulated DCs were used as a control. (B) IL-10 and IL-12p70 production by DCs after stimulation with various concentrations of LPS (1 ng/mL-500 ng/mL) for 24 hours. (C) The concentration of IL-10 and IL-12p70 by DCs following stimulation with 500 ng/mL LPS for various lengths of time. Unstimulated DCs were used as a control. Values in panels A to C are expressed as means plus or minus standard deviation. (D) Purified DO11.10 CD4⁺ T cells were cocultured with imDCs or maDCs or/and diffDCs treated with or without 500 ng/mL LPS for 24 hours in the presence of OVA_323-339 at a ratio of 1:10 (DC/T); LCMV-NP_309-328 (NP) was used as an Ia^b-restricted peptide control. After 5 days, cells were collected and double-stained with anti-CD4–FITC and 7-AAD and counted by FACS. *P < .05.