FIG 3.

Properties of secreted HEV RNA. (A) Apical (black line) and basolateral (gray line) supernatants (10⁵ copies of HEV RNA) were loaded onto a 7.5 to 40% iodixanol gradient, ultracentrifuged, and fractionated. The percentage of HEV RNA in each fraction (density) is shown. The density gradients are representative of the results of three independent experiments. (B to E) Apical (black line) and basolateral (gray line) supernatants containing 10⁴ copies of HEV RNA genotype 3 (B) or HEV genotype 1 (D) were loaded onto 7.5 to 40% iodixanol minigradients. (C and E) The same samples were treated with 1% NP-40 and ultracentrifuged. Untreated feces from HEV genotype 3 (10⁴ copies of HEV RNA) were added as controls (C, dashed line). (F) The infectivity of apical or basolateral supernatants from F2 cells infected with HEV genotype 3 was evaluated using an endpoint dilution assay, and the TCID₅₀ per million HEV RNA copies was calculated (n = 6). Each symbol represents a pair of apical and basolateral supernatants from the same insert. The bars indicate medians. **, P < 0.01. (G) The infectivity of apical or basolateral supernatants of F2 cells infected with eHEV genotype 1 was evaluated as for panel F (n = 3). The bars represent medians.