Live virus neutralization testing in convalescent patients and subjects vaccinated against 19A, 20B, 20I/501Y.V1 and 20H/501Y.V2 isolates of SARS-CoV-2

ABSTRACT

SARS-CoV-2 mutations appeared recently and can lead to conformational changes in the spike protein and probably induce modifications in antigenicity. We assessed the neutralizing capacity of antibodies to prevent cell infection, using a live virus neutralization test with different strains [19A (initial one), 20B (B.1.1.241 lineage), 20I/501Y.V1 (B.1.1.7 lineage), and 20H/501Y.V2 (B.1.351 lineage)] in serum samples collected from different populations: two-dose vaccinated COVID-19-naive healthcare workers (HCWs; Pfizer-BioNTech BNT161b2), 6-months post mild COVID-19 HCWs, and critical COVID-19 patients. No significant difference was observed between the 20B and 19A isolates for HCWs with mild COVID-19 and critical patients. However, a significant decrease in neutralization ability was found for 20I/501Y.V1 in comparison with 19A isolate for critical patients and HCWs 6-months post infection. Concerning 20H/501Y.V2, all populations had a significant reduction in neutralizing antibody titers in comparison with the 19A isolate. Interestingly, a significant difference in neutralization capacity was observed for vaccinated HCWs between the two variants but not in the convalescent groups.

KEYWORDS:

• SARS-CoV-2
• humoral response
• variant of concern
• live virus neutralization test
• 20B
• 20I/501Y.V1
• 20H/501Y.V2

Acknowledgements

We are indebted to all the personnel of the occupational health and medicine department of Hospices Civils de Lyon who contributed to the collection of samples, especially Virginie Pitiot, Fanny Joubert and PMO team. Human biological samples and associated data were obtained from NeuroBioTec (CRB HCL, Lyon France, Biobank BB-0033-00046). We thank Karima Brahami and all members of the clinical research and innovation department for their reactivity (DRS, Hospices Civils de Lyon). All members of Saint-Etienne Hospital who contributed to the collection of samples are acknowledged. COVID-SER study group: Alfaiate Dulce, d'Aubarede Constance, Escuret Vanessa, Fassier Jean-Baptiste, Gaymard Alexandre, Grégory Destras, Guibert Nicolas, Lozano Hélène, Massardier-Pilonchery Amélie, Pitiot Virginie.

Disclosure statement

Antonin Bal received a grant from bioMerieux and served as consultant for bioMerieux for work and research not related to this manuscript. Sophie Trouillet-Assant received a research grant from bioMerieux concerning previous works not related to this manuscript. The other authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript.

Data availability statement

GISAID accession numbers: EPI_ISL_1707038; EPI_ISL_1707039; EPI_ISL_1707040; EPI_ISL_768828.

Additional information

Funding

This research is being supported by Hospices Civils de Lyon, Fondation des Hospices Civils de Lyon, and a grant from the GIMAP team of the University Hospital of Saint-Etienne (Grant reference: the ASSE Coeur-vert association).