title: Glycan masking of hemagglutinin for adenovirus vector and recombinant protein immunizations elicits broadly neutralizing antibodies against H5N1 avian influenza viruses.
abstract: The highly pathogenic avian influenza (HPAI) H5N1 virus, a known trigger of diseases in poultry and humans, is perceived as a serious threat to public health. There is a clear need for a broadly protective H5N1 vaccine or vaccines for inducing neutralizing antibodies against multiple clades/subclades. We constructed single, double, and triple mutants of glycan-masked hemagglutiinin (HA) antigens at residues 83, 127 and 138 (i.e., g83, g127, g138, g83+g127, g127+g138, g83+g138 and g83+g127+g138), and then obtained their corresponding HA-expressing adenovirus vectors and recombinant HA proteins using a prime-boost immunization strategy. Our results indicate that the glycan-masked g127+g138 double mutant induced more potent HA-inhibition, virus neutralization antibodies, cross-clade protection against heterologous H5N1 clades, correlated with the enhanced bindings to the receptor binding sites and the highly conserved stem region of HA. The immune refocusing stem-specific antibodies elicited by the glycan-masked H5HA g127+g138 and g83+g127+g138 mutants overlapped with broadly neutralizing epitopes of the CR6261 monoclonal antibody that neutralizes most group 1 subtypes. These findings may provide useful information in the development of a broadly protective H5N1 influenza vaccine.
authors.affiliation: Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: Shih-Chang
authors.initials: SC
authors.lastname: Lin
authors.affiliation: Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: Wen-Chun
authors.initials: WC
authors.lastname: Liu
authors.affiliation: Genomics Research Center, Academia Sinica, Taipei, Taiwan.
authors.forename: Jia-Tsrong
authors.initials: JT
authors.lastname: Jan
authors.affiliation: Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan; Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: Suh-Chin
authors.initials: SC
authors.lastname: Wu
mesh_terms: D000256:Adenoviridae / Q000378:metabolism*; D000818:Animals; D057134:Antibodies, Neutralizing / Q000276:immunology*; D000914:Antibodies, Viral / Q000276:immunology; D000956:Antigens, Viral / Q000276:immunology; D056738:Cross Protection / Q000276:immunology; D005260:Female; D005822:Genetic Vectors; D006385:Hemagglutination Inhibition Tests; D006388:Hemagglutinins / Q000276:immunology*; D007114:Immunization; D007074:Immunoglobulin G / Q000276:immunology; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology; D020128:Inhibitory Concentration 50; D008807:Mice, Inbred BALB C; D008958:Models, Molecular; D050505:Mutant Proteins / Q000378:metabolism; D009976:Orthomyxoviridae Infections / Q000276:immunology / Q000821:virology; D011134:Polysaccharides / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology*; D013045:Species Specificity
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D000956:Antigens, Viral; D006388:Hemagglutinins; D007074:Immunoglobulin G; D007252:Influenza Vaccines; D050505:Mutant Proteins; D011134:Polysaccharides; D011994:Recombinant Proteins