Evaluation of a pseudotyped virus neutralisation test for measurement of equine influenza A virus neutralizing antibody responses induced by vaccination and infection

Kinsley, Rebecca; Pronost, St�phane; De Bock, Manuelle; Temperton, Nigel; Daly, Janet M; Paillot, Romain; Scott, Simon

Abstract

Equine influenza is a major respiratory disease of horses that is largely controlled by 24 vaccination in some equine populations. Virus-neutralizing antibodies, the mainstay of the protective 25 immune response, are problematic to assay for equine influenza virus as most strains do not replicate 26 efficiently in cell culture. Surrogate measures of protective antibody responses include the 27 haemagglutination inhibition (HI) test and single radial haemolysis (SRH) assay. For this study, a 28 pseudotyped virus bearing an envelope containing the haemagglutinin (HA) from the Florida clade 29 2 equine influenza virus strain A/equine/Richmond/1/07 (H3N8) was generated to measure HA-30 specific neutralizing antibodies in serum samples (n=134) from vaccinated or experimentally-infected 31 ponies using a pseudotyped virus neutralisation test (PVNT). Overall, the results of PVNT were in 32 good agreement with results from the SRH assay (100% sensitivity, 68.53% specificity) and HI test 33 (99.2% sensitivity, 49.03% specificity). The PVNT was apparently more sensitive than either the SRH 34 assay or HI test, which could be advantageous for studying the antibody kinetics, particularly when 35 antibody levels are low. Nevertheless, further studies are required to determine whether a protective 36 antibody level can be defined as for the SRH assay and to ascertain the inter-laboratory 37 reproducibility. In conclusion, the PVNT efficiently measures neutralising antibodies after 38 immunisation and/or experimental infection in the natural host and may complement existing 39 antibody assays. 40

Citation

Kinsley, R., Pronost, S., De Bock, M., Temperton, N., Daly, J. M., Paillot, R., & Scott, S. (2020). Evaluation of a pseudotyped virus neutralisation test for measurement of equine influenza A virus neutralizing antibody responses induced by vaccination and infection. Vaccines, 8(3), https://doi.org/10.3390/vaccines8030466

• Journal Article Type: Article
• Acceptance Date: Aug 15, 2020
• Online Publication Date: Aug 21, 2020
• Publication Date: Aug 21, 2020
• Deposit Date: Aug 17, 2020
• Publicly Available Date: Aug 21, 2020
• Journal: Vaccines
• Electronic ISSN: 2076-393X
• Publisher: MDPI
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 3
• Article Number: 466
• DOI: https://doi.org/10.3390/vaccines8030466
• Keywords: equine influenza; horse; pseudotype virus; vaccine
• Public URL: https://nottingham-repository.worktribe.com/output/4840181
• Publisher URL: https://www.mdpi.com/2076-393X/8/3/466