Frontiers in Immunology (Nov 2023)

Detection of anti-SARS-CoV-2 salivary antibodies in vaccinated adults

  • Vitória Tavares Castro,
  • Hélène Chardin,
  • Hélène Chardin,
  • Juliana Amorim dos Santos,
  • Gustavo Barcelos Barra,
  • Grazielle Rodrigues Castilho,
  • Paula Monteiro Souza,
  • Pérola de Oliveira Magalhães,
  • Ana Carolina Acevedo,
  • Eliete Neves Silva Guerra

DOI
https://doi.org/10.3389/fimmu.2023.1296603
Journal volume & issue
Vol. 14

Abstract

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Since the introduction of efficient anti-SARS-CoV-2 vaccines, the detection of antibodies becomes useful for immunological monitoring and COVID-19 control. Therefore, this longitudinal study aimed to evaluate the detection of SARS-CoV-2 antibodies in the serum and saliva of COVID-19-vaccinated adults. The study included 13 not vaccinated and 35 vaccinated participants with two doses of CoronaVac (Sinovac/Butantan) vaccine who subsequently received BNT162b2 (Pfizer-BioNTech) vaccine as a booster dose. Vaccinated participants donated saliva and serum in three different time points. Enzyme-linked immunosorbent assay was used for antibody detection. In our results, the serum neutralizing antibodies (NAb) were detected in 34/35 samples after second dose and in 35/35 samples one and five months after the booster dose. In saliva, NAb were detected in 30/35 samples after second dose and in 35/35 of samples one and five months after the booster dose. IgA was detected in 19/34 saliva samples after second dose, in 18/35 one month after the booster and in 30/35 five months after. IgG in saliva was detected in 1/34 samples after second dose, 33/35 samples one month after the booster dose and in 20/35 five months after. A strong correlation was found between IgG and neutralizing activity in saliva, and salivary IgA would be a sign of recent exposure to the virus. In conclusion, saliva can be suitable for monitoring antibodies anti-SARS-CoV-2 after vaccination. Heterologous vaccination contributed to increase anti-SARS-CoV-2 antibodies in the Brazilian health context. Complementary studies with large groups are mandatory to conclude the interest in following mucosal immunity.

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