Analysis of 17D yellow fever virus envelope protein epitopes using monoclonal antibodies

Sixteen monoclonal antibodies that reacted with the envelope glycoprotein (E) of 17D vaccine strain yellow fever virus (17D YF), including two antibodies produced against dengue 2 virus, were used in a solid phase competitive binding assay (CBA) to define spatial relationships among antigenic determinants on 17D YF E. The antibodies showed YF strain, type or flavivirus group specificities and nine epitopes were identified on 17D YF E by patterns of neutralization, haemagglutination inhibition and competition of antibody binding. Epitopes defined by neutralizing antibodies with strain and type specificities appeared spatially distant but competition between type-specific neutralizing antibodies and some non-neutralizing antibodies against type and group determinants suggested close proximity among epitopes in these regions. Despite competition between some neutralizing and non-neutralizing monoclonal antibodies in CBA, plaque assays revealed no interference with neutralization by non-neutralizing antibody.