Figure 4. Pf gDNA induces IL-1β through activation of AIM2 inflammasome.

(a) 50 and 100 ng/ml of Pf gDNA (3D7) were transfected using lipofectamine into LPS primed (100ng/ml × 2h) immortalized murine wt, Nlrp3^−/−, Asc^−/− and casp1^−/− BMDMs. After 12h, IL-1β was measured in the culture supernatants by ELISA. (b) 100ng/ml of gDNA from different strains of Pf (Dd2, T9/94, HB3-B2) was transfected using lipofectamine into LPS-primed primary Aim2^+/+ and Aim2^−/− BMDMs. Cell culture supernatants were used to measure IL-1β using ELISA. Data are presented as mean ± SD of triplicates and are representative of 3 independent experiments. (c) Confocal microscopy of LPS primed ASC-CFP cells left untrasfected or transfected with 100ng/ml Syto60-labeled Pf gDNA. Scale bar: 20µm (top), 5µm (bottom) (d) Confocal microscopy of LPS primed AIM2-citrine macrophages left untransfected or transfected with 100ng/ml DAPI-labeled Pf gDNA, DAPI-labeled poly (dAdT) using lipofectamine or just incubated with sHz. Scale bar (from top to bottom): 15µm, 5µm, 15µm and 15µm. (e) Confocal microscopy of NLRP3-citrine macrophages untreated or treated with sHz/CpG (5µg/ml), sHz/Pf gDNA (4µg/ml), nigericin or transfected with 100ng/ml Pf gDNA using Lipofectamine. Images are representative of at least 10 fields of view and three independent experiments. Scale bar: All 20µm except the one in the bottom which is 5µm. See also Fig. S4.