FIG 3.

CpG does not induce parasite killing within infected mouse bone marrow-derived macrophages. Bone marrow-derived macrophages were infected with late-stationary-phase L. (V.) panamensis promastigotes (isolated from Percoll gradients as indicated) for 4 h, washed, and then incubated for 24, 48, or 72 h with (i) CpG 1826 (1 or 5 μM), (ii) miltefosine (20 μM, positive control; Sigma), (iii) 72-h supernatants from dLN cell cultures (as described in the text), or (iv) 72-h supernatants from dLN cell cultures together with CpG 1826 (1 or 5 μM). Following staining with Giemsa (Fluke Analytical, Sigma-Aldrich), the mean number of parasites per macrophage (B) and the percentage of parasitized macrophages (A) were calculated by counting 100 macrophages per sample, in triplicate per determination. Data represent those from one of three independent experiments. *, P ≤ 0.05; **, P ≤ 0.01; and ***, P ≤ 0.001 compared to control. #, P ≤ 0.05; ##, P ≤ 0.01; and ###, P ≤ 0.001 compared to supernatant alone.