Characterization of a Novel Neutralizing Monoclonal Antibody Against Ebola Virus GP

Ebola virus is the etiological agent of a severe hemorrhagic fever with a high mortality rate. As the only protein exposed on the surface of viral particles, the spike glycoprotein GP is the unique target for neutralizing mono-clonal antibodies. In this study, we demonstrate the strong neutralization capacity of the monoclonal antibody #3327 and characterize its activity. GP residues that are required for recognition and neutralization were found to be located both in the internal fusion loop and in the receptor-binding domain. Analysis of Ebola virus entry in the presence of #3327 allows us to hypothesize that this antibody binds to the virus particle before internal-ization and endosomal processing of GP and likely prevents the final viral fusion step. Importantly, #3327 is able to block entry of virions bearing GP that contain the Q508 escape mutation common to a number of virus-neutralizing antibodies, and therefore provides future perspectives for treatment strategies against Ebola virus infection. Keywords. Ebola virus; glycoprotein GP; virus neutralizing antibody; filovirus. Ebola virus (EBOV) causes a severe form of hemorrhagic fever in humans and nonhuman primates [1–3]. EBOV is member of the family Filoviridae, a group of en-veloped, nonsegmented, negative-strand RNA viruse