ABSTRACT
Objective To establish the universal antibody against all subtypes of the influenza A viral hemagglutinins(HA). Methods All HA sequences from influenza viruses in common domains were analyzed to search for the most conservative re,on of the HA gene. The peptides conjugated to carrier proteins were used to immunize rabbits in order to obtain high titer antibody. Results The most conservative region among all influenza viruses HA genes were 14 amino acids located at the N-terminal of HA2. The antibody titer reached to 1 : 80 000 after 4 injections of the coupled peptides. The achieved antibody was demonstrated by Western blot to bind HA proteins of influenza virus subtypes H1-H13 specifically. Conclusion The universal antibody has been successfully established by immunizing the rabbits with most conservative peptides of HA protein coupled to carrier protein.
ABSTRACT
The fusion peptide is the only universally conserved sequence in the hemagglutinins of all 16 subtypes of influenza A and two genetic lineages of influenza B viruses. Here, peptides selected by bioinformatics approach were modified and conjugated to overcome serious technical hurdles such as the high hydrophobicity and weak immunogenicity of the viral fusion peptides. Antibodies generated against fusion peptides demonstrated remarkable specificity against the viral sequences and robustness of quantitatively analyzing the viral hemagglutinins even under stringent conditions. As quantitatively revealed by antibody-binding experiments, the fusion peptides of diverse hemagglutinins are exposed to the same degree upon unfolding at neutral pH to the physiologically fusogenic state. To our knowledge, this is the first report on the quantitative determination of virtually all influenza vaccines using a single universal antibody.
