Evidence against an important role for infectivity-enhancing antibodies in Ebola virus infections.

The neutralizing and enhancing activities of Ebola virus (EBOV)-specific antibodies were tested among four murine antibodies specific to the surface glycoprotein (GP), a recombinant human monoclonal antibody specific to GP, a polyclonal equine IgG, and serum obtained from a convalescent monkey. All but one of these antibodies neutralized EBOV infectivity of primary human monocytes/macrophages or Vero cells. None of the antibodies enhanced EBOV infectivity in these cells. Taken together with in vivo observations that early deaths were not observed in animals immunized with various viral vectors expressing EBOV GP, it is unlikely that any EBOV-enhancing antibodies profoundly affected EBOV pathogenesis.