Antibody-mediated uncoating of adenovirus in vitro.

In a virus destabilization assay in vitro it was demonstrated that exposure of adenovirus to proteins will non-specifically protect the virus from being uncoated following transfer to low pH and hypotonic conditions. Such uncoating was also fully inhibited upon pretreatment of virus with 0.05% of the non-ionic detergent polyoxyethylenesorbitan monolaurate (Tween 20). However, in the presence of low concentrations of Tween 20 it was shown that monospecific immunoglobulins, directed against the fiber antigen and polyspecific antibodies produced in response to intact virions, were able to overcome the detergent-protecting effect of uncoating. Immunoglobulins directed towards the remaining outer-capsid components, the hexon, the penton base and the protein IIIa, revealed no such effects. The antifiber-mediated uncoating was paralleled by an aggregation of the virions. The data suggest that the virion-stabilizing effect of salt is enhanced by the hydrophobic action of a non-ionic detergent. Under these conditions the interaction between antifiber antibodies and fibers of the virion will trigger a destabilization of the virion upon transfer to low pH and hypotonic conditions.