Evidence map›Paper›PMID 42339829›Full record

ArticleMicrobiology spectrum2026

ELISA-based quantification of neuraminidase in commercial influenza vaccines using virus-derived reference antigens.

Hyeog Kang, Jin Gao, Luca Giurgea, Matthew J Memoli, Robert Daniels

Abstract read
In one paragraph

Article in Microbiology spectrum, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Review
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Hyeog KangDivision of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA.ORCID 0000-0001-8935-1103
Jin GaoDivision of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA.
Luca GiurgeaLaboratory of Infectious Diseases Clinical Studies Unit, Laboratory of Infectious Diseases, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.ORCID 0000-0002-8696-6927
Matthew J MemoliLaboratory of Infectious Diseases Clinical Studies Unit, Laboratory of Infectious Diseases, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
Robert DanielsDivision of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA.ORCID 0000-0002-5988-2920

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Most commercial influenza vaccines are produced using inactivated viruses decorated with hemagglutinin (HA) and neuraminidase (NA) antigens from the recommended strains. However, only the HA antigen content is monitored, leaving the NA antigen content, stability, and potential contributions to efficacy unclear. We quantified functional NA amounts in commercial vaccines from two seasons by coupling NA enzyme-linked immunosorbent assays (ELISAs) with NA reference antigens that were isolated from egg-propagated vaccine strains (H1N1, H3N2, and type B) by Immobilized NA Active site Affinity Chromatography (INAAC). Our results show that nonexpired egg-based vaccines for the 2024-25 season contained the three expected NAs and that cell-based vaccines may require cell propagated NA reference antigens. NA amounts in egg-based vaccines varied by strain and manufacturer, ranging from 0.7 to 1.7 µg/dose or NA:HA ratios between 1:10 and 1:20. We confirmed the ELISA results with an NA activity analysis, indicating functional NA amounts were measured. In expired egg-based vaccines (2022-23 season), some NAs were at low or undetectable levels, indicative of structural integrity decay over time. These findings provide a foundation for quantifying NA content and stability in vaccines to evaluate NA's potential efficacy contributions and optimize the design of future influenza vaccines that contain both NA and HA.IMPORTANCEThe influenza virus surface antigens hemagglutinin (HA) and neuraminidase (NA) are both targeted by the immune system during infection. Although most licensed influenza vaccines contain both the HA and NA antigens from the recommended strains, only the HA content is monitored. Here, we measured functional NA amounts in commercial vaccines using a stability-indicating ELISA with NA reference antigens isolated from the vaccine viruses. Our results show that current egg-based vaccines contain the expected NAs at amounts that vary by strain and manufacturer. Expired vaccines had reduced or undetectable NA levels, suggesting NA may degrade over time. This methodology can be applied to measure NA content and stability in current vaccines and help to optimize the design of future vaccines that contain both NA and HA antigens.

Indexed as

Antigens, ViralInfluenza VaccinesNeuraminidaseViral ProteinsAnimalsEnzyme-Linked Immunosorbent AssayHemagglutinin Glycoproteins, Influenza VirusHumansInfluenza A Virus, H1N1 SubtypeInfluenza A Virus, H3N2 SubtypeInfluenza B virusInfluenza, HumanAntigens, ViralHemagglutinin Glycoproteins, Influenza VirusInfluenza VaccinesNeuraminidaseViral ProteinsH1N1H3N2INAACinfluenza NA active-site affinity chromatographyinfluenza vaccine antigen contentNA purificationNA vaccine standardsseasonal influenza vaccinestype B influenza virus

Identifiers

PMID42339829
PMCPMC13435686

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