|
Basic Characteristics of Mutations
|
|
Mutation Site
|
N125D |
|
Mutation Site Sentence
|
Haemagglutinin substitutions N125D, D127E, D222G and R223Q improve replicative fitness and vaccine effectiveness of an A/H1N1pdm09 live attenuated influenza vaccine virus by enhancing alpha-2,6 receptor binding. |
|
Mutation Level
|
Amino acid level |
|
Mutation Type
|
Nonsynonymous substitution |
|
Gene/Protein/Region
|
HA |
|
Standardized Encoding Gene
|
HA
|
|
Genotype/Subtype
|
H1N1 |
|
Viral Reference
|
A/SLOV15;A/MICH15
|
|
Functional Impact and Mechanisms
|
|
Disease
|
Influenza A
|
|
Immune
|
- |
|
Target Gene
|
-
|
|
Clinical and Epidemiological Correlations
|
|
Clinical Information
|
- |
|
Treatment
|
- |
|
Location
|
- |
|
Literature Information
|
|
PMID
|
35622874
|
|
Title
|
Haemagglutinin substitutions N125D, D127E, D222G and R223Q improve replicative fitness and vaccine effectiveness of an A/H1N1pdm09 live attenuated influenza vaccine virus by enhancing alpha-2,6 receptor binding
|
|
Author
|
Dempsey R,Tamburrino G,Schewe KE,Crowe J,Nuccitelli A,Dibben O
|
|
Journal
|
PLoS pathogens
|
|
Journal Info
|
2022 May 27;18(5):e1010585
|
|
Abstract
|
During 2013-14 and 2015-16, A/H1N1pdm09 live attenuated influenza vaccine (LAIV) viruses replicated inefficiently in primary human nasal epithelial cells (hNEC). This led to reduced vaccine effectiveness (VE) in quadrivalent formulations, mediated by inter-strain competition. By mutating the haemagglutinin (HA) protein, we aimed to enhance hNEC replication of a novel A/H1N1pdm09 vaccine strain to overcome competition and improve VE. Combinations of N125D, D127E, D222G and R223Q substitutions were introduced to the HA protein of A/Slovenia/2903/2015 (A/SLOV15). A/SLOV15 S13, containing all four HA substitutions, produced approximately 1000-fold more virus than parental V1 during hNEC infection. Immunogenicity in ferrets was increased by approximately 10-fold, without compromising yield in eggs or antigenic match to wild-type (wt) reference strains. Despite S13 and V1 being antigenically similar, only S13 protected ferrets from wt virus shedding and fever post-challenge. Crucially, these data suggested that enhanced fitness allowed S13 to overcome inter-strain competition in quadrivalent LAIV (QLAIV). This improved efficacy was later validated by real-world VE data. S13 displayed increased binding avidity to a mammalian-like alpha-2,6 receptor analogue (6-SLN), relative to V1, while maintaining avian-like 3-SLN avidity. In silico modelling of the HA receptor binding site revealed additional interactions in the S13:6-SLN binding network and a mild increase in 6-SLN binding energy, indicating a possible mechanism for increased alpha-2,6 receptor-binding avidity. These data confirm that rational HA mutagenesis can be used to optimise hNEC replication and VE for A/H1N1pdm09 LAIV viruses.
|
|
Sequence Data
|
-
|
|
|