Figure 6

Deposition of HZ in DCs suppresses maturation. (a) HZ content in bone-marrow-derived DCs (In vitro), purified DCs (Ex vivo) and spleen sections (In vivo) was visualized by light microscopy (top images) or by false-coloring malaria pigment viewed in bright-field image (red) and superimposing over the fluorescent CD11c image (green). (b) CD11c⁺ DCs were analyzed for size and granularity by flow cytometry 12 days post-infection with P. chabaudi or in uninfected controls. Data are expressed as the mean forward scatter or side scatter of triplicate samples ± 1 s.d. (*p ≤ 0.05, ^#p ≤ 0.005 uninfected versus P. chabaudi-infected). (c-e) 2 × 10⁶ DCs were cultured with 1 μM, 5 μM, 10 μM and 20 μM of HZ. After 24 h, the level of expression of (c) MHC class II, (d) CD40 and (e) CD86 on CD11c⁺ cells was determined by FACS analysis. (f-h) After 24 h culture with HZ, 1 μg/ml LPS was added to DCs and the levels of (f) MHC class II, (g) CD40, and (h) CD86 were analyzed 18 h later by FACS. All results are shown as the mean fluorescence intensity on CD11c⁺ DCs in triplicate samples ± s.e. (^*p ≤ 0.05 HZ versus LPS).