Influenza virus M2e with additional cysteine residues shows enhanced immunogenicity and protection against lethal virus challenge.
The amino acid sequence of the extracellular domain of matrix protein 2 (M2e) is conserved among all subtypes of influenza A viruses. Therefore, the M2e peptide can be considered as a target antigen for the development of a universal influenza vaccine. We evaluated the effects of adding cysteine residues to a peptide of amino acids 2-24 of M2e. Mice immunized with some of these peptides containing one, two, three, four, or five extra cysteines displayed enhanced antibody titers to M2e. In addition, immunization with a peptide containing three extra cysteines, along with an aluminum adjuvant, protected mice more effectively against a lethal influenza virus challenge than the original M2e peptide. These results indicated that an M2e peptide containing additional cysteine residues could be a universal influenza vaccine candidate even without the addition of strong adjuvants.
Applied Research Department, Kikuchi Research Center, The Chemo-sero-therapeutic Research Institute, Kikuchi-city, Kumamoto, Japan.
Kazuyoshi
K
Kaminaka
Jun-Ichi
J
Matsuda
Chikateru
C
Nozaki
D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology*; D000917:Antibody Formation / Q000276:immunology; D005260:Female; D007114:Immunization; D007252:Influenza Vaccines / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009975:Orthomyxoviridae / Q000276:immunology*; D009976:Orthomyxoviridae Infections / Q000276:immunology* / Q000517:prevention & control*
D000914:Antibodies, Viral; D007252:Influenza Vaccines; C509609:M2e-HBc influenza vaccine