Epitope-guided optimization improves the protective efficacy of NA-based mRNA vaccines against seasonal influenza A(H3N2) virus.
5 affiliations
- 1Department of Microbiology, Institute for Viral Diseases, Korea University College of Medicine, Seoul 02841, Republic of Korea
- 2Division of Infectious Diseases Vaccine Research, Center for Vaccine Research, National Institute of Infectious Diseases, Korea National Institute of Health, Cheongju 28159, Republic of Korea
- 3Department of Lab Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan 48108, Republic of Korea
- 4Vaccine Innovation Center, Korea University College of Medicine, Seoul 02841, Republic of Korea
- 5Biosafety Center, Korea University College of Medicine, Seoul 02841, Republic of Korea
Abstract
Neuraminidase (NA) is increasingly recognized as a promising target antigen for improving the breadth and durability of influenza vaccines, yet NA-based mRNA vaccines remain comparatively unexplored relative to hemagglutinin-based approaches. Here, we applied a computationally guided NA antigen-design strategy to seasonal H3N2 influenza viruses and investigated whether epitope-guided optimization could improve the immunogenicity and protective efficacy of NA-based mRNA vaccines. NA-D3, an NA antigen designed based on the evolutionary characteristics of circulating H3N2 viruses, was first evaluated in an mRNA vaccine. This vaccine provided partial protection against H3N2 challenge and reduced viral replication in the lungs, although detectable neuraminidase inhibition (NAI) activity was not observed. To further improve NA antigen immunogenicity, predicted B- and T-cell epitopes were incorporated into the antigen design process, resulting in three sequentially optimized NA candidates, F0, F1, and F2. In a subsequent challenge experiment, F1 and F2 conferred complete protection, achieving 100% survival and significantly lower viral RNA levels and infectious viral titers in the lungs compared to controls. The optimized NA mRNA vaccines also induced detectable NAI activity against heterologous H3N2 viruses, albeit at relatively modest levels. Collectively, these findings demonstrate the protective potential of NA-based mRNA vaccination against H3N2 influenza viruses and establish iterative, epitope-guided strategy in NA antigen optimization - integrating computational prediction with experimental validation - as an effective approach for developing broadly protective NA-based mRNA vaccines.
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BibTeX
@article{kim2026epitopeguided,
title = {{Epitope-guided optimization improves the protective efficacy of NA-based mRNA vaccines against seasonal influenza A(H3N2) virus.}},
author = {Hyunbeen Kim and Sangyi Lee and Seunghye Cho and Woojin Shin and Soyoung Lee and Atanas V. Demirev and Taeyoung Lee and You-Jin Kim and Dokeun Kim and Sae Am Song and Kyung Ran Jun and Jin Il Kim},
journal = {Journal of microbiology (Seoul, Korea)},
year = {2026},
month = oct,
doi = {10.71150/jm.2609004},
url = {https://europepmc.org/article/MED/42958806},
note = {CC BY},
}
RIS
TY - JOUR
TI - Epitope-guided optimization improves the protective efficacy of NA-based mRNA vaccines against seasonal influenza A(H3N2) virus.
AU - Hyunbeen Kim
AU - Sangyi Lee
AU - Seunghye Cho
AU - Woojin Shin
AU - Soyoung Lee
AU - Atanas V. Demirev
AU - Taeyoung Lee
AU - You-Jin Kim
AU - Dokeun Kim
AU - Sae Am Song
AU - Kyung Ran Jun
AU - Jin Il Kim
PY - 2026
DA - 2026/10/31
JO - Journal of microbiology (Seoul, Korea)
DO - 10.71150/jm.2609004
UR - https://europepmc.org/article/MED/42958806
AB - Neuraminidase (NA) is increasingly recognized as a promising target antigen for improving the breadth and durability of influenza vaccines, yet NA-based mRNA vaccines remain comparatively unexplored relative to hemagglutinin-based approaches. Here, we applied a computationally guided NA antigen-design strategy to seasonal H3N2 influenza viruses and investigated whether epitope-guided optimization could improve the immunogenicity and protective efficacy of NA-based mRNA vaccines. NA-D3, an NA antigen designed based on the evolutionary characteristics of circulating H3N2 viruses, was first evaluated in an mRNA vaccine. This vaccine provided partial protection against H3N2 challenge and reduced viral replication in the lungs, although detectable neuraminidase inhibition (NAI) activity was not observed. To further improve NA antigen immunogenicity, predicted B- and T-cell epitopes were incorporated into the antigen design process, resulting in three sequentially optimized NA candidates, F0, F1, and F2. In a subsequent challenge experiment, F1 and F2 conferred complete protection, achieving 100% survival and significantly lower viral RNA levels and infectious viral titers in the lungs compared to controls. The optimized NA mRNA vaccines also induced detectable NAI activity against heterologous H3N2 viruses, albeit at relatively modest levels. Collectively, these findings demonstrate the protective potential of NA-based mRNA vaccination against H3N2 influenza viruses and establish iterative, epitope-guided strategy in NA antigen optimization - integrating computational prediction with experimental validation - as an effective approach for developing broadly protective NA-based mRNA vaccines.
SN - 1225-8873
SN - 1976-3794
ER -