mRNA vaccination drives differential mucosal neutralizing antibody profiles in naïve and SARS-CoV-2 previously-infected individuals

Journal article

The ComFluCOV trial randomized 679 participants to receive an age-appropriate influenza vaccine, or placebo, alongside their second COVID-19 vaccine. Concomitant administration was shown to be safe, and to preserve systemic immune responses to both vaccines. Here we report on a secondary outcome of the trial investigating SARS-CoV-2-specific mucosal antibody responses. Anti-spike IgG and IgA levels in saliva were measured with in-house ELISAs. Concomitant administration of an influenza vaccine did not affect salivary anti-spike IgG positivity rates to Pfizer/BioNTech BNT162b2 (99.1 cf. 95.6%), or AstraZeneca ChAdOx1 (67.8% cf. 64.9%), at 3-weeks post-vaccination relative to placebo. Furthermore, saliva IgG positively correlated with serum titres highlighting the potential utility of saliva for assessing differences in immunogenicity in future vaccine studies. Mucosal IgA was not detected in response to either COVID-19 vaccine, reinforcing the need for novel vaccines capable of inducing sterilising immunity or otherwise reducing transmission. The trial is registered as ISRCTN 14391248

Authors: Longet, S; Hargreaves, A; Healy, S; Brown, R; Hornsby, HR

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Frontiers Media
• Journal: Frontiers in Immunology
• Volume: 13
• Pages: 953949-953949
• Article number: 953949
• Publication date: 2022-09-08
• DOI: 10.3389/fimmu.2022.953949
• EISSN: 1664-3224
• ISSN: 1664-3224
• Language: English
• Keywords: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); Infectious disease (medical specialty); Medicine; Antibody; Immunoglobulin G; Immunoassay; Internal medicine; Disease; Coronavirus disease 2019 (COVID-19); Virology; Immunoglobulin A; Neutralizing antibody; Immune system; Vaccination; Immunology