Neutralising reactivity against SARS-CoV-2 Delta and Omicron variants by vaccination and infection history

Genome Medicine

Margherita Cattai¹  Monia Pacenti¹  Caterina Boldrin¹  Chiara Zulian¹  Maria Cristina Vanuzzo¹  Vittoria Lisi¹  Giovanni Tonon²  Ludovico Fava³  Gioele Castelli³  Michele Nicoletti³  Mario Plebani⁴  Andrea Padoan⁴  Marco Grazioli⁵  Maria Antonello⁵  Carmela Ileana Grimaldi⁵  Margherita Sartori⁵  Andrea Crisanti⁵  Enrico Lavezzo⁵  Stefano Toppo⁵  Laura Manuto⁵  Claudia Del Vecchio⁵  Federico Bianca⁵  Alessandra R. Brazzale⁶  Eleonora Nieddu⁷  Daniela Maria Cirillo⁸  Federico Caldart⁹  Ilaria Dorigatti^1,10  Beatrice Labella^1,11  Elisa Salvadoretti^1,12 

[1] Azienda Ospedale Padova;Center for Omics Sciences, IRCCS Ospedale San Raffaele;Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padova;Department of Medicine, University of Padova;Department of Molecular Medicine, University of Padova;Department of Statistical Sciences, University of Padova;Department of Surgery, Oncology and Gastroenterology, University of Padova;Emerging Bacterial Pathogens Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute;Gastroenterology Unit, Department of Medicine, Verona B. Roma University Hospital;MRC Centre for Global Infectious Disease Analysis and Jameel Institute, School of Public Health, Imperial College London;Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia;Paediatrics Unit, Mother and Child Hospital, Surgery, Dentistry, Maternity and Infant Department, Verona University Hospital;

关键词: SARS-CoV-2;    COVID-19;    Antibody persistence;    Neutralising antibodies;    Delta variant;    Omicron variant;   

DOI  :  10.1186/s13073-022-01066-2

来源: DOAJ

【 摘 要 】

Abstract Background The continuous emergence of SARS-CoV-2 variants of concern (VOC) with immune escape properties, such as Delta (B.1.617.2) and Omicron (B.1.1.529), questions the extent of the antibody-mediated protection against the virus. Here we investigated the long-term antibody persistence in previously infected subjects and the extent of the antibody-mediated protection against B.1, B.1.617.2 and BA.1 variants in unvaccinated subjects previously infected, vaccinated naïve and vaccinated previously infected subjects. Methods Blood samples collected 15 months post-infection from unvaccinated (n=35) and vaccinated (n=41) previously infected subjects (Vo’ cohort) were tested for the presence of antibodies against the SARS-CoV-2 spike (S) and nucleocapsid (N) antigens using the Abbott, DiaSorin, and Roche immunoassays. The serum neutralising reactivity was assessed against B.1, B.1.617.2 (Delta), and BA.1 (Omicron) SARS-CoV-2 strains through micro-neutralisation. The antibody titres were compared to those from previous timepoints, performed at 2- and 9-months post-infection on the same individuals. Two groups of naïve subjects were used as controls, one from the same cohort (unvaccinated n=29 and vaccinated n=20) and a group of vaccinated naïve healthcare workers (n=61). Results We report on the results of the third serosurvey run in the Vo’ cohort. With respect to the 9-month time point, antibodies against the S antigen significantly decreased (P=0.0063) among unvaccinated subjects and increased (P<0.0001) in vaccinated individuals, whereas those against the N antigen decreased in the whole cohort. When compared with control groups (naïve Vo’ inhabitants and naïve healthcare workers), vaccinated subjects that were previously infected had higher antibody levels (P<0.0001) than vaccinated naïve subjects. Two doses of vaccine elicited stronger anti-S antibody response than natural infection (P<0.0001). Finally, the neutralising reactivity of sera against B.1.617.2 and BA.1 was 4-fold and 16-fold lower than the reactivity observed against the original B.1 strain. Conclusions These results confirm that vaccination induces strong antibody response in most individuals, and even stronger in previously infected subjects. Neutralising reactivity elicited by natural infection followed by vaccination is increasingly weakened by the recent emergence of VOCs. While immunity is not completely compromised, a change in vaccine development may be required going forward, to generate cross-protective pan-coronavirus immunity in the global population.

【 授权许可】

Unknown