Natural SARS-CoV-2 Infection Affects Neutralizing Activity in Saliva of Vaccinees

Author:

Garziano Micaela,Utyro Olga,Poliseno Mariacristina,Santantonio Teresa Antonia,Saulle Irma,Strizzi Sergio,Lo Caputo Sergio,Clerici Mario,Introini Andrea,Biasin Mara

Abstract

BackgroundSARS-CoV-2 transmission mainly occurs through exposure of the upper airway mucosa to infected secretions such as saliva, which are excreted by an infected person. Thus, oral mucosal immunity plays a central role in the prevention of and early defense against SARS-CoV-2 infection. Although virus-specific antibody response has been extensively investigated in blood samples of SARS-CoV-2-infected patients and vaccinees, local humoral immunity in the oral cavity and its relationship to systemic antibody levels needs to be further addressed.Material and MethodsWe fine-tuned a virus neutralization assay (vNTA) to measure the neutralizing activity (NA) of plasma and saliva samples from 20 SARS-CoV-2-infected (SI), 40 SARS-CoV-2-vaccinated (SV), and 28 SARS-CoV-2-vaccinated subjects with a history of infection (SIV) using the “wild type” SARS-CoV-2 lineage B.1 (EU) and the Delta (B.1.617.2) strains. To validate the vNTA results, the presence of neutralizing antibodies (NAbs) to the spike receptor binding domain (RBD) was evaluated with an ELISA assay.ResultsNA to SARS-CoV-2 lineage B.1 (EU) was present in plasma samples from all the tested subjects, with higher titers in SIV compared to both SI and SV. Conversely, NA was detected in saliva samples from 10.3% SV, 45% SI, and 92.6% SIV, with significantly lower titers in SV compared to both SI and SIV. The detection of NAbs in saliva reflected its reduced NA in SV.DiscussionThe difference in NA of plasma vs. saliva was confirmed in a vNTA where the SARS-CoV-2 B.1 and Delta strains were tested head-to-head, which also revealed a reduced NA of both specimens compared to the B.1 variant.ConclusionsThe administration of SARS-CoV-2 vaccines was associated with limited virus NA in the oral cavity, as measured in saliva and in comparison to plasma. This difference was more evident in vaccinees without a history of SARS-CoV-2 infection, possibly highlighting the importance of local exposure at the site of virus acquisition to effectively prevent the infection and block its spread. Nevertheless, the presence of immune escape mutations as possibly represented by the SARS-CoV-2 Delta variant negatively affects both local and systemic efficacy of NA associated with vaccination.

Funder

Regione Lombardia

Fondazione Cariplo

Publisher

Frontiers Media SA

Subject

Immunology,Immunology and Allergy

Reference49 articles.

1. Molecular Interaction and Inhibition of SARS-CoV-2 Binding to the ACE2 Receptor;Yang;Nat Commun,2020

2. A Novel Coronavirus From Patients With Pneumonia in China, 2019;Zhu;N Engl J Med,2020

3. Identifying Airborne Transmission as the Dominant Route for the Spread of COVID-19;Zhang;Proc Natl Acad Sci U S A,2020

4. COVID-19 Serology at Population Scale: SARS-CoV-2-Specific Antibody Responses in Saliva;Pisanic;J Clin Microbiol,2020

5. A Mucosal Antibody Response is Induced by Intra-Muscular SARS-CoV-2 mRNA VaccinationMedrxiv

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