Exogenous ATP does not induce IL-1β secretion by DCs.

Supernatants from LPS-treated DCs, cultured 6 hours without (lanes 1 and 2) or with (lanes 3 and 4) alloreactive T cells at a DC/T cell ratio of 1:10, unstimulated (lanes 1 and 3) or stimulated (lanes 2 and 4) with 1 mM ATP for the last 15 minutes were analyzed by Western blotting for their content in secreted IL-1β (A) and cathepsin D (B); pro-CD indicates procathepsin D. One representative experiment of 3 is shown.