Neutralization. However, in heterotypic dengue virus infections the antibodies are non-neutralizing and lead to enhancement. Two cell lines expressing either FcRIA or FcRIIA have been used to demonstrate that immune complexes can enhance virus infectivity in an FcR mediated fashion. FcRIA is found exclusively on macrophages and dendritic cells and preferentially binds monomeric IgG, while FcRIIA i