TLR agonists stimulate regulatory diffDCs to produce a higher level of IP-10 than imDCs. (A) IP-10 mRNA expression in imDCs or diffDCs cultured in medium alone as a control (0) or stimulated with LPS at the indicated time. The transcript of mouse GAPDH gene was used as the amplification control. (B) IP-10 production by imDCs or diffDCs stimulated with various concentrations of LPS (1 ng to 1 μg/mL) for 24 hours was measured. imDCs and diffDCs cultured in medium (untreated DCs) were used as controls. (C) IP-10 production by imDCs or diffDCs following stimulation with 500 ng/mL LPS for various lengths of time was measured. (D) At 24 hours after stimulation of imDCs or diffDCs (5 × 105 cells/mL) with 500 ng/mL LPS, 1 μM CpG ODN, 5 ng/mL LTA, 1 μg/mL poly(I:C) or 50 ng/mL HSP70, IP-10 production was measured by ELISA. Values in panels B-D are expressed as means ± SD. Results are representative of 3 independent experiments.
