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Post-vaccination T cell immunity to omicron.

ABSTRACT: In late 2021, the omicron variant of SARS Coronavirus 2 (SARS-CoV-2) emerged and replaced the previously dominant delta strain. Effectiveness of COVID-19 vaccines against omicron has been challenging to estimate in clinical studies or is not available for all vaccines or populations of interest. T cell function can be predictive of vaccine longevity and effectiveness against disease, likely in a more robust way than antibody neutralization. In this mini review, we summarize the evidence on T cell immunity against omicron including effects of boosters, homologous versus heterologous regimens, hybrid immunity, memory responses and vaccine product. Overall, T cell reactivity in post-vaccine specimens is largely preserved against omicron, indicating that vaccines utilizing the parental antigen continue to be protective against disease caused by the omicron variant.

SUBMITTER: Jacobsen H

PROVIDER: S-EPMC9386871 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Post-vaccination T cell immunity to omicron.

Jacobsen Henning H Cobos Jiménez Viviana V Sitaras Ioannis I Bar-Zeev Naor N Čičin-Šain Luka L Higdon Melissa M MM Deloria-Knoll Maria M

Frontiers in immunology 20220726

In late 2021, the omicron variant of SARS Coronavirus 2 (SARS-CoV-2) emerged and replaced the previously dominant delta strain. Effectiveness of COVID-19 vaccines against omicron has been challenging to estimate in clinical studies or is not available for all vaccines or populations of interest. T cell function can be predictive of vaccine longevity and effectiveness against disease, likely in a more robust way than antibody neutralization. In this mini review, we summarize the evidence on T cel ...[more]

PMID: 35990661

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Limited cross-variant immunity from SARS-CoV-2 Omicron without vaccination.

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Additive effects of booster mRNA vaccination and SARS-CoV-2 Omicron infection on T cell immunity across immunocompromised states.

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