Antigenic Drift of Influenza A(H7N9) Virus Hemagglutinin.
J Infect Dis
; 219(1): 19-25, 2019 01 01.
Article
em En
| MEDLINE
| ID: mdl-29982588
ABSTRACT
Background:
Since the emergence of influenza A(H7N9) virus in 2013, there have been 5 waves of influenza A(H7N9) epidemics in China. However, evolution of the hemagglutinin (HA) protein antigenicity has not been systematically investigated.Methods:
To better understand how antigenic drift in HA proteins of influenza (A)H7N9 virus occurs, 902 influenza A(H7N9) virus HA protein sequences from a public database were retrieved and analyzed. Fifty-three mutants with single amino acid substitutions in HA protein were introduced into pseudoviruses, and their antigenic characteristics were analyzed using pseudovirus-based assays.Results:
The frequencies of 9 mutations incrementally increased over the past 5 years, with mutations identified at multiple sites. While mean neutralization titers of most variants remained unchanged, 3 mutations, A143V, A143T, and R148K, displayed a median 4-fold lower susceptibility to neutralization by antisera against influenza A/Anhui/1/2013(H7N9) virus. Notably, A143V and A143T were located outside the previously reported antigenic sites. The most dominant variant (A143V/R148K) in the most recent season constituted 74.11% of all mutations and demonstrated a 10-fold reduction in its reactivity to influenza A/Anhui/1/2013(H7N9) virus antisera. Importantly, compared with the DNA construct without the corresponding HA protein mutation, DNA vaccine encoding the A143V/R148K mutant induced a 5-fold increase in the neutralizing activity against this circulating virus.Conclusions:
An appropriate vaccine strain should be considered in response to increasing antigenic drift in influenza A(H7N9) virus HA protein.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Glicoproteínas de Hemaglutininação de Vírus da Influenza
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Substituição de Aminoácidos
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Subtipo H7N9 do Vírus da Influenza A
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Antígenos Virais
Tipo de estudo:
Prognostic_studies
Limite:
Animals
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Female
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Humans
País como assunto:
Asia
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article