Increased immunogenicity and protective efficacy of influenza M2e fused to a tetramerizing protein.
The ectodomain of the matrix 2 protein (M2e) of influenza A virus represents an attractive target for developing a universal influenza A vaccine, with its sequence being highly conserved amongst human variants of this virus. With the aim of targeting conformational epitopes presumably shared by diverse influenza A viruses, a vaccine (M2e-NSP4) was constructed linking M2e (in its consensus sequence) to the rotavirus fragment NSP4(98-135); due to its coiled-coil region this fragment is known to form tetramers in aqueous solution and in this manner we hoped to mimick the natural configuration of M2e as presented in membranes. M2e-NSP4 was then evaluated side-by-side with synthetic M2e peptide for its immunogenicity and protective efficacy in a murine influenza challenge model. Here we demonstrate that M2e fused to the tetramerizing protein induces an accelerated, augmented and more broadly reactive antibody response than does M2e peptide as measured in two different assays. Most importantly, vaccination with M2e-NSP4 caused a significant decrease in lung virus load early after challenge with influenza A virus and maintained its efficacy against a lethal challenge even at very low vaccine doses. Based on the results presented in this study M2e-NSP4 merits further investigation as a candidate for or as a component of a universal influenza A vaccine.
Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
Anne-Marie Carola
AM
Andersson
Kjell O
KO
Håkansson
Benjamin Anderschou Holbech
BA
Jensen
Dennis
D
Christensen
Peter
P
Andersen
Allan Randrup
AR
Thomsen
Jan Pravsgaard
JP
Christensen
D000595:Amino Acid Sequence; D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006023:Glycoproteins / Q000235:genetics / Q000276:immunology*; D006367:HeLa Cells; D006801:Humans; D009980:Influenza A virus / Q000235:genetics* / Q000276:immunology*; D007252:Influenza Vaccines / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D053208:Kaplan-Meier Estimate; D008168:Lung / Q000187:drug effects / Q000821:virology; D051379:Mice; D008969:Molecular Sequence Data; D009976:Orthomyxoviridae Infections / Q000276:immunology* / Q000517:prevention & control; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014118:Toxins, Biological / Q000235:genetics / Q000276:immunology*; D019562:Viral Load / Q000276:immunology; D014763:Viral Matrix Proteins / Q000235:genetics / Q000276:immunology*; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000276:immunology*; D000086082:Viroporin Proteins
D000914:Antibodies, Viral; D017931:DNA Primers; D006023:Glycoproteins; D007252:Influenza Vaccines; D014118:Toxins, Biological; D014763:Viral Matrix Proteins; D017361:Viral Nonstructural Proteins; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins; C081369:NS28 protein, rotavirus