Immature DENV particles of different serotypes can be rendered infectious by heterotypic human serum.

<p>P388D1 cells were infected with MOG 1000 of std (grey bars) and pre-opsonized immature (black bars) DENV-1 (A) or DENV-4 (B) as described in the text. At least two independent experiments were performed in triplicate. Limit of detection is 20 FFU/ml. Error bars represent SEM. N.d. denotes for “not detectable”. Levels of significance (Mann Whitney U test) are presented as ** = p<0.01.