Adenosine reduces the capacity of iDCs to activate allogeneic T cells.

DCs were treated (filled symbols) or not (open symbols) with 10⁻⁴ M adenosine in the absence (A) or in the presence (B) of 3 μg/mL LPS for 48 hours at 37°C. Thereafter, DCs were washed and cocultured with purified allogeneic CD4⁺CD45RA⁺ T cells (10⁵cells/well) in 96-well plates. ³H-thymidine incorporation was measured after 5 days. Background T-cell proliferation was less than 1000 counts per minute (cpm). In panel A, differences in T-cell proliferation were significant (P < .02) at more than 312 DCs/well. Results are representative of 4 different experiments. Data are means ± SD (n = 3).