%A Chan,Renee W. Y. %A Liu,Shaojun %A Cheung,Jonathan Y. %A Tsun,Joseph G. S. %A Chan,Kate C. %A Chan,Kathy Y. Y. %A Fung,Genevieve P. G. %A Li,Albert M. %A Lam,Hugh Simon %D 2021 %J Frontiers in Immunology %C %F %G English %K mucosal immunity,nasal epithelial lining fluid,Immunoglobulin A,Immunoglobulin G,serological immunity,mRNA vaccine,inactivated virus vaccine,SARS – CoV – 2 %Q %R 10.3389/fimmu.2021.744887 %W %L %M %P %7 %8 2021-October-12 %9 Original Research %+ Renee W. Y. Chan,Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong,Hong Kong, SAR China,reneewy@cuhk.edu.hk %+ Renee W. Y. Chan,Laboratory for Paediatric Respiratory Research, Li Ka Shing Institute of Health Sciences, Faculty of Medicine, The Chinese University of Hong Kong,Hong Kong, SAR China,reneewy@cuhk.edu.hk %+ Renee W. Y. Chan,The Chinese University of Hong Kong–University Medical Center Utrecht Joint Research Laboratory of Respiratory Virus and Immunobiology, Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong,Hong Kong, SAR China,reneewy@cuhk.edu.hk %+ Renee W. Y. Chan,Hong Kong Hub of Paediatric Excellence, The Chinese University of Hong Kong,Hong Kong, SAR China,reneewy@cuhk.edu.hk %+ Dr Hugh Simon Lam,Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong,Hong Kong, SAR China,reneewy@cuhk.edu.hk %+ Dr Hugh Simon Lam,Laboratory for Paediatric Respiratory Research, Li Ka Shing Institute of Health Sciences, Faculty of Medicine, The Chinese University of Hong Kong,Hong Kong, SAR China,reneewy@cuhk.edu.hk %# %! Mucosal Immunity after SARS-CoV-2 vaccines %* %< %T The Mucosal and Serological Immune Responses to the Novel Coronavirus (SARS-CoV-2) Vaccines %U https://www.frontiersin.org/articles/10.3389/fimmu.2021.744887 %V 12 %0 JOURNAL ARTICLE %@ 1664-3224 %X BackgroundAlthough the serological antibody responses induced by SARS-CoV-2 vaccines are well characterized, little is known about their ability to elicit mucosal immunity.ObjectivesThis study aims to examine and compare the mucosal and systemic responses of recipients of two different vaccination platforms: mRNA (Comirnaty) and inactivated virus (CoronaVac).MethodsSerial blood and nasal epithelial lining fluid (NELF) samples were collected from the recipients of either Comirnaty or CoronaVac. The plasma and NELF immunoglobulins A and G (IgA and IgG) specific to SARS-CoV-2 S1 protein (S1) and their neutralization effects were quantified.ResultsComirnaty induced nasal S1-specific immunoglobulin responses, which were evident as early as 14 ± 2 days after the first dose. In 64% of the subjects, the neutralizing effects of NELF persisted for at least 50 days. Moreover, 85% of Comirnaty recipients exhibited S1-specific IgA and IgG responses in plasma by 14 ± 2 days after the first dose. By 7 ± 2 days after the booster, all plasma samples possessed S1-specific IgA and IgG responses and were neutralizing. The induction of S1-specific plasma antibodies by CoronaVac was IgG dominant, and 83% of the subjects possessed S1-specific IgG by 7 ± 2 days after the booster, with neutralizing effects.ConclusionComirnaty induces S1-specific IgA and IgG responses with neutralizing activity in the nasal mucosa; a similar response is not seen with CoronaVac.Clinical ImplicationThe presence of a nasal response with mRNA vaccine may provide additional protection compared with inactivated virus vaccine. However, whether such widespread immunological response may produce inadvertent adverse effects in other tissues warrants further investigation.