IDENTIFICATION OF A CONSERVED NEUTRALIZATION SITE IN THE FIRST HEPTADREPEAT OF THE FUSION PROTEIN OF RESPIRATORY SYNCYTIAL VIRUS

A large set of monoclonal antibodies (MAbs) directed against the fusio n glycoprotein complex F1F2 of bovine respiratory syncytial virus (BRS V) and several polyclonal sera from infected or vaccinated animals wer e tested in Pepscan to locate linear epitopes on the F-protein. The po lyclonal sera mapped to antigenic sites that correspond exactly to kno wn antigenic sites on the F protein of human RSV. Only the neutralizin g MAb 3 could be mapped with Pepscan. MAb 3 reacted with three success ive overlapping Linear peptides that shared the amino acid sequence (1 73)STNKAVVSLS(182). The sequence of this novel neutralization site is conserved in all known BRSV- and human RSV-strains and is located on t he N-terminus of F-1, adjacent to the hydrophobic, putative fusion-rel ated region. This region is probably part of a central coiled-coil ste m that is structurally conserved in paramyxovirus fusion and orthomyxo virus hemagglutinin glycoproteins. This linear conserved epitope may b e a potential candidate for a peptide-based vaccine which can induce n eutralizing antibodies against all groups and subgroups of RSV. Furthe rmore, the proposed structural features of the neutralization site may aid in the design of a peptide-based vaccine.