Fig. 2.

The effect of GNF179 on the liver stage parasite and a comparison with lasalocid, pyrimethamine and atovaquone. (A) High-resolution deconvolution microscopy of the GNF179-treated liver-stage parasites. Columns show Hoechst 33342 staining in blue, αPyHSP70 staining in red and a merge with the host plasma membrane marker CD81-GFP in green. Cultures were treated with 1 μM GNF179 for 48 hr. (Insets) DMSO-treated control parasite at the same scale and time point. Scale bar indicates 10 μm. (B) Chemical structure of GNF1.79. (C) The targets of GNF179 and lasalocid appear to be required throughout development. Compounds were added at 1 μM final concentration at the start (lightest shaded bars), 15 hpi (medium shaded bars) and 27 hpi (darkest shaded bars); all samples were incubated up to an end-point of 51 hpi. Dashed lines represent the control DMSO-treated growth levels at 15, 27 and 51 hpi. Data are mean +/− SD from 2 experimental replicats of approx. 50 infected cells per time point. Las, lasalocid; Pyr, pyrimethamine; Atov, atovaquone. (D) In vivo bioluminescence imaging of representative mice infected with P. berghei and treated with GNF179 (15 mg/kg) or vehicle (no compound), at 6 hpi. In the control, luminescence showing the developing parasite was detected in the liver area from 24 hpi and the lung and gastrointestinal track region from 72 hpi. No luminescence signal was detected from GNF179 or atovaquone (2.5 mg/kg) -treated mice even at the maximum sensitivity setting and no blood stage parasitemia was detected from later blood smear examinations. The luminescence intensity color-coding does not represent absolute values and is individually adjusted for each recording, which is why you can see background signal around the muzzle in some of the control pictures.