tetano
Editor, Senior Moderator
J Gen Virol. 2016 Mar 31. doi: 10.1099/jgv.0.000468. [Epub ahead of print]
[h=1]Vaccine-associated enhanced respiratory disease is influenced by hemagglutinin and neuraminidase in whole inactivated influenza virus vaccines.[/h] Raj?o DS[SUP]1[/SUP], Chen H[SUP]2[/SUP], Perez DR[SUP]3[/SUP], Sandbulte MR[SUP]4[/SUP], Gauger PC[SUP]5[/SUP], Loving CL[SUP]6[/SUP], Shanks GD[SUP]7[/SUP], Vincent AL[SUP]8[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Multiple subtypes and many antigenic variants of influenza A virus (IAV) co-circulate in swine in the USA, complicating effective use of commercial vaccines to control disease and transmission. Whole inactivated virus (WIV) vaccines may provide partial protection against IAV with substantial antigenic drift, but have been shown to induce vaccine-associated enhanced respiratory disease (VAERD) when challenged with an antigenic variant of the same hemagglutinin (HA) subtype. This study investigated the role the immune response against HA, neuraminidase (NA), and nucleoprotein (NP) may play in VAERD by reverse engineering vaccine and challenge viruses on a common backbone and using them in a series of vaccination/challenge trials. Mismatched HA between vaccine and challenge virus was necessary to induce VAERD. However, vaccines containing a matched NA abrogated the VAERD phenomenon induced by the HA mismatch and was correlated with NA-inhibiting (NI) antibodies. Divergence between the two circulating swine N2 lineages (92% identity) resulted in a loss of NI cross-reactivity and also resulted in VAERD with the mismatched HA. The NP lineage selected for use in the WIV vaccine strains did not affect protection or pathology. Thus the combination of HA and NA in the vaccine virus strains played substantial roles in vaccine protection versus immunopathology, suggesting that vaccines that target the HA protein alone could be more prone to VAERD due to the absence of cross-protective NI antibodies.
PMID: 27031847 [PubMed - as supplied by publisher]
[h=1]Vaccine-associated enhanced respiratory disease is influenced by hemagglutinin and neuraminidase in whole inactivated influenza virus vaccines.[/h] Raj?o DS[SUP]1[/SUP], Chen H[SUP]2[/SUP], Perez DR[SUP]3[/SUP], Sandbulte MR[SUP]4[/SUP], Gauger PC[SUP]5[/SUP], Loving CL[SUP]6[/SUP], Shanks GD[SUP]7[/SUP], Vincent AL[SUP]8[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Multiple subtypes and many antigenic variants of influenza A virus (IAV) co-circulate in swine in the USA, complicating effective use of commercial vaccines to control disease and transmission. Whole inactivated virus (WIV) vaccines may provide partial protection against IAV with substantial antigenic drift, but have been shown to induce vaccine-associated enhanced respiratory disease (VAERD) when challenged with an antigenic variant of the same hemagglutinin (HA) subtype. This study investigated the role the immune response against HA, neuraminidase (NA), and nucleoprotein (NP) may play in VAERD by reverse engineering vaccine and challenge viruses on a common backbone and using them in a series of vaccination/challenge trials. Mismatched HA between vaccine and challenge virus was necessary to induce VAERD. However, vaccines containing a matched NA abrogated the VAERD phenomenon induced by the HA mismatch and was correlated with NA-inhibiting (NI) antibodies. Divergence between the two circulating swine N2 lineages (92% identity) resulted in a loss of NI cross-reactivity and also resulted in VAERD with the mismatched HA. The NP lineage selected for use in the WIV vaccine strains did not affect protection or pathology. Thus the combination of HA and NA in the vaccine virus strains played substantial roles in vaccine protection versus immunopathology, suggesting that vaccines that target the HA protein alone could be more prone to VAERD due to the absence of cross-protective NI antibodies.
PMID: 27031847 [PubMed - as supplied by publisher]