Zika virus (ZIKV) has emerged in dengue (DENV) endemic areas, where these two related flaviviruses continue to co-circulate. DENV is a complex of four serotypes and infections can progress to severe disease. It is thought that this is mediated by antibody dependent enhancement (ADE) whereby antibodies from a primary DENV infection are incapable of neutralizing heterologous DENV infections with another serotype. ADE has been demonstrated among other members of the Flavivirus group.
We utilize an in vitro ADE assay developed for DENV to determine whether ZIKV is enhanced by a commonly available DENV serotype 2-derived monoclonal antibody (4G2).
We show that ZIKV infection in vitro is enhanced in the presence of the 4G2 mAb.
Our results demonstrate that ADE between ZIKV and DENV is possible and that the 4G2 antibody is a useful tool for the effects of pre-existing anti-DENV antibodies during ZIKV infections.