title: Targeting the HA2 subunit of influenza A virus hemagglutinin via CD40L provides universal protection against diverse subtypes.
abstract: The influenza viral hemagglutinin (HA) is comprised of two subunits. Current influenza vaccine predominantly induces neutralizing antibodies (Abs) against the HA1 subunit, which is constantly evolving in unpredictable fashion. The other subunit, HA2, however, is highly conserved but largely shielded by the HA head domain. Thus, enhancing immune response against HA2 could potentially elicit broadly inhibitory Abs. We generated a recombinant adenovirus (rAd) encoding secreted fusion protein, consisting of codon-optimized HA2 subunit of influenza A/California/7/2009(H1N1) virus fused to a trimerized form of murine CD40L, and determined its ability of inducing protective immunity upon intranasal administration. We found that mice immunized with this recombinant viral vaccine were completely protected against lethal challenge with divergent influenza A virus subtypes including H1N1, H3N2, and H9N2. Codon-optimization of HA2 as well as the use of CD40L as a targeting ligand/molecular adjuvant were indispensable to enhance HA2-specific mucosal IgA and serum IgG levels. Moreover, induction of HA2-specific T-cell responses was dependent on CD40L, as rAd secreting HA2 subunit without CD40L failed to induce any significant levels of T-cell cytokines. Finally, sera obtained from immunized mice were capable of inhibiting 13 subtypes of influenza A viruses in vitro. These results provide proof of concept for a prototype HA2-based universal influenza vaccine.
authors: 1] National Institutes for Food and Drug Control, Beijing, China [2] Department of Biopharmaceutics, School of Pharmacy, Fourth Military Medical University, Xi'an, China.
authors: X
authors: X
authors: Fan
authors: 1] Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, Ontario, Canada [2] Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia [3] Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia [4] Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada.
authors: A M
authors: AM
authors: Hashem
authors: Shanghai Institute of Biological Products, Shanghai, China.
authors: Z
authors: Z
authors: Chen
authors: National Institutes for Food and Drug Control, Beijing, China.
authors: C
authors: C
authors: Li
authors: 1] Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, Ontario, Canada [2] Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada.
authors: T
authors: T
authors: Doyle
authors: Department of Biopharmaceutics, School of Pharmacy, Fourth Military Medical University, Xi'an, China.
authors: Y
authors: Y
authors: Zhang
authors: Shanghai Institute of Biological Products, Shanghai, China.
authors: Y
authors: Y
authors: Yi
authors: Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, Ontario, Canada.
authors: A
authors: A
authors: Farnsworth
authors: National Institutes for Food and Drug Control, Beijing, China.
authors: K
authors: K
authors: Xu
authors: National Institutes for Food and Drug Control, Beijing, China.
authors: Z
authors: Z
authors: Li
authors: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.
authors: R
authors: R
authors: He
authors: 1] Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, Ontario, Canada [2] Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada.
authors: X
authors: X
authors: Li
authors: National Institutes for Food and Drug Control, Beijing, China.
authors: J
authors: J
authors: Wang
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D057134:Antibodies, Neutralizing / Q000276:immunology; D000940:Antigenic Variation; D023201:CD40 Ligand / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004285:Dogs; D005260:Female; D057809:HEK293 Cells; D006367:HeLa Cells; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007114:Immunization; D009980:Influenza A virus / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D061985:Madin Darby Canine Kidney Cells; D051379:Mice; D008807:Mice, Inbred BALB C; D058990:Molecular Targeted Therapy; D015202:Protein Engineering; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary / Q000235:genetics; D021122:Protein Subunits / Q000235:genetics / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage* / Q000235:genetics; D013045:Species Specificity
chemical_list: D057134:Antibodies, Neutralizing; C543345:H1N1 virus hemagglutinin; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007252:Influenza Vaccines; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D023201:CD40 Ligand