Polyclonal and monoclonal antibodies specific for the six-helix bundle of the human respiratory syncytial virus fusion glycoprotein as probes of the protein post-fusion conformation

• Published in: Virology (New York, N.Y.) Vol. 460; pp. 119 - 127
• Main Authors: Palomo, Concepción, Mas, Vicente, Vázquez, Mónica, Cano, Olga, Luque, Daniel, Terrón, María C, Calder, Lesley J, Melero, José A
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-07-2014
• Subjects: 60 APPLIED LIFE SCIENCES; ANCHORS; Animals; Antibodies, Monoclonal - analysis; Antibodies, Monoclonal - immunology; Antibodies, Viral - analysis; Antibodies, Viral - immunology; CONFORMATIONAL CHANGES; ELECTRON MICROSCOPY; GLYCOPROTEINS; Humans; Infectious Disease; LIPIDS; MEMBRANES; MOLECULES; MONOCLONAL ANTIBODIES; MUTAGENESIS; PEPTIDES; Post-fusion specific antibodies against RSV F glycoprotein; Protein Structure, Secondary; RABBITS; Respiratory Syncytial Virus Infections - virology; Respiratory Syncytial Virus, Human - chemistry; Respiratory Syncytial Virus, Human - genetics; Respiratory Syncytial Virus, Human - immunology; Viral Fusion Proteins - chemistry; Viral Fusion Proteins - genetics; Viral Fusion Proteins - immunology; VIRUSES; Post-fusion specific antibodies against RSV F glycoprotein
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1016/j.virol.2014.05.001

Abstract Human respiratory syncytial virus (hRSV) has two major surface glycoproteins (G and F) anchored in the lipid envelope. Membrane fusion promoted by hRSV_F occurs via refolding from a pre-fusion form to a highly stable post-fusion state involving large conformational changes of the F trimer. One of these changes results in assembly of two heptad repeat sequences (HRA and HRB) into a six-helix bundle (6HB) motif. To assist in distinguishing pre- and post-fusion conformations of hRSV_F, we have prepared polyclonal (α-6HB) and monoclonal (R145) rabbit antibodies specific for the 6HB. Among other applications, these antibodies were used to explore the requirements of 6HB formation by isolated protein segments or peptides and by truncated mutants of the F protein. Site-directed mutagenesis and electron microscopy located the R145 epitope in the post-fusion hRSV_F at a site distantly located from previously mapped epitopes, extending the repertoire of antibodies that can decorate the F molecule.