tetano
Editor, Senior Moderator
Front Immunol
. 2023 Dec 20:14:1327875.
doi: 10.3389/fimmu.2023.1327875. eCollection 2023. Contribution of SARS-CoV-2 infection preceding COVID-19 mRNA vaccination to generation of cellular and humoral immune responses in children
Marije K Verheul[SUP] 1 [/SUP], Martijn Vos[SUP] 1 [/SUP], Lia de Rond[SUP] 1 [/SUP], Mary-Lène De Zeeuw-Brouwer[SUP] 1 [/SUP], Kim H Nijhof[SUP] 1 [/SUP], Debbie Smit[SUP] 1 [/SUP], Debbie Oomen[SUP] 1 [/SUP], Petra Molenaar[SUP] 1 [/SUP], Marjan Bogaard[SUP] 1 [/SUP], Rianne van Bergen[SUP] 1 [/SUP], Irene Middelhof[SUP] 1 [/SUP], Lisa Beckers[SUP] 1 [/SUP], Alienke J Wijmenga-Monsuur[SUP] 1 [/SUP], Anne-Marie Buisman[SUP] 1 [/SUP], Mardi C Boer[SUP] 1 [/SUP], Rob van Binnendijk[SUP] 1 [/SUP], Jelle de Wit[SUP] 1 [/SUP], Teun Guichelaar[SUP] 1 [/SUP]
Affiliations
Primary COVID-19 vaccination for children, 5-17 years of age, was offered in the Netherlands at a time when a substantial part of this population had already experienced a SARS-CoV-2 infection. While vaccination has been shown effective, underlying immune responses have not been extensively studied. We studied immune responsiveness to one and/or two doses of primary BNT162b2 mRNA vaccination and compared the humoral and cellular immune response in children with and without a preceding infection. Antibodies targeting the original SARS-CoV-2 Spike or Omicron Spike were measured by multiplex immunoassay. B-cell and T-cell responses were investigated using enzyme-linked immunosorbent spot (ELISpot) assays. The activation of CD4[SUP]+[/SUP] and CD8[SUP]+[/SUP] T cells was studied by flowcytometry. Primary vaccination induced both a humoral and cellular adaptive response in naive children. These responses were stronger in those with a history of infection prior to vaccination. A second vaccine dose did not further boost antibody levels in those who previously experienced an infection. Infection-induced responsiveness prior to vaccination was mainly detected in CD8[SUP]+[/SUP] T cells, while vaccine-induced T-cell responses were mostly by CD4[SUP]+[/SUP] T cells. Thus, SARS-CoV-2 infection prior to vaccination enhances adaptive cellular and humoral immune responses to primary COVID-19 vaccination in children. As most children are now expected to contract infection before the age of five, the impact of infection-induced immunity in children is of high relevance. Therefore, considering natural infection as a priming immunogen that enhances subsequent vaccine-responsiveness may help decision-making on the number and timing of vaccine doses.
Keywords: B cells; COVID-19 vaccine; SARS-CoV-2; T cells; adaptive; antibodies; children; infection.
. 2023 Dec 20:14:1327875.
doi: 10.3389/fimmu.2023.1327875. eCollection 2023. Contribution of SARS-CoV-2 infection preceding COVID-19 mRNA vaccination to generation of cellular and humoral immune responses in children
Marije K Verheul[SUP] 1 [/SUP], Martijn Vos[SUP] 1 [/SUP], Lia de Rond[SUP] 1 [/SUP], Mary-Lène De Zeeuw-Brouwer[SUP] 1 [/SUP], Kim H Nijhof[SUP] 1 [/SUP], Debbie Smit[SUP] 1 [/SUP], Debbie Oomen[SUP] 1 [/SUP], Petra Molenaar[SUP] 1 [/SUP], Marjan Bogaard[SUP] 1 [/SUP], Rianne van Bergen[SUP] 1 [/SUP], Irene Middelhof[SUP] 1 [/SUP], Lisa Beckers[SUP] 1 [/SUP], Alienke J Wijmenga-Monsuur[SUP] 1 [/SUP], Anne-Marie Buisman[SUP] 1 [/SUP], Mardi C Boer[SUP] 1 [/SUP], Rob van Binnendijk[SUP] 1 [/SUP], Jelle de Wit[SUP] 1 [/SUP], Teun Guichelaar[SUP] 1 [/SUP]
Affiliations
- PMID: 38193077
- PMCID: PMC10773747
- DOI: 10.3389/fimmu.2023.1327875
Primary COVID-19 vaccination for children, 5-17 years of age, was offered in the Netherlands at a time when a substantial part of this population had already experienced a SARS-CoV-2 infection. While vaccination has been shown effective, underlying immune responses have not been extensively studied. We studied immune responsiveness to one and/or two doses of primary BNT162b2 mRNA vaccination and compared the humoral and cellular immune response in children with and without a preceding infection. Antibodies targeting the original SARS-CoV-2 Spike or Omicron Spike were measured by multiplex immunoassay. B-cell and T-cell responses were investigated using enzyme-linked immunosorbent spot (ELISpot) assays. The activation of CD4[SUP]+[/SUP] and CD8[SUP]+[/SUP] T cells was studied by flowcytometry. Primary vaccination induced both a humoral and cellular adaptive response in naive children. These responses were stronger in those with a history of infection prior to vaccination. A second vaccine dose did not further boost antibody levels in those who previously experienced an infection. Infection-induced responsiveness prior to vaccination was mainly detected in CD8[SUP]+[/SUP] T cells, while vaccine-induced T-cell responses were mostly by CD4[SUP]+[/SUP] T cells. Thus, SARS-CoV-2 infection prior to vaccination enhances adaptive cellular and humoral immune responses to primary COVID-19 vaccination in children. As most children are now expected to contract infection before the age of five, the impact of infection-induced immunity in children is of high relevance. Therefore, considering natural infection as a priming immunogen that enhances subsequent vaccine-responsiveness may help decision-making on the number and timing of vaccine doses.
Keywords: B cells; COVID-19 vaccine; SARS-CoV-2; T cells; adaptive; antibodies; children; infection.