FIG. 1.

Flotation gradient analysis of Ebola virus protein-induced VLPs. Human 293T cells were transfected with VP40 (A), GP (B), VP24 (C), or NP (D), and VLPs were isolated from the culture medium at 48 hpt. VLPs were isolated by centrifugation through a 20% sucrose cushion and subsequently floated on a discontinuous (80-50-10%) sucrose gradient. One-milliliter fractions were taken from top (lane 1) to bottom (lane 12). Proteins in each fraction as well as in the cell lysate (lane 13) were isolated by trichloroacetic acid precipitation, separated by SDS-PAGE, and analyzed by Western blotting.