FIG 6.

MAbs c2G4 and c4G7 do not block binding of the NPC1 C-loop to primed (19-kDa) EBOV GP. VLPs bearing EBOV-Mayinga GP were mock treated or (thermolysin) treated (to 19 kDa) and then bound (triplicate samples) to a high-bind ELISA plate. After washing and blocking, MAbs c2G4, c4G7, or c13C6 (50 μg/well; PBS for the control) were added, and the plate incubated for 1.5 h at room temperature. After washing, 0.2 μg/ml soluble NPC1 C-loop (PBS for no NPC1 C-loop samples) was added, followed by incubation for 1 h at room temperature. After washing (PBS), the plate was processed to detect soluble C-loop binding as described in Materials and Methods. Data are the averages ± the SD. Cleavage of full-length GP to 19 kDa was confirmed by Western blotting with a rabbit anti-GP antibody (a gift from Paul Bates) as described in Materials and Methods. Lane 1, mock treated GP; lane 2, (thermolysin) treated GP. Band labeling is as described in the Fig. 5 legend.