FIG. 2.

Chloroquine attenuates IL-12 p40 production in DCs from A/J mice (A), macrophages from A/J mice (B), and DCs from BALB/c mice (C). Cells were pretreated with chloroquine (100 μM) for 30 min prior to stimulation (Stm) with killed L. pneumophila (kLp), ODN1826, living L. pneumophila (Lp), or LPS for 24 h. Culture supernatants were analyzed for IL-12 p40 by ELISA, and the data are means ± SEM for three to six experiments. Panel D shows the numbers of L. pneumophila CFU in DC cultures from A/J and BALB/c mice treated with chloroquine and also in A/J macrophages. BM, bone marrow. *, P < 0.05.