Assessment of SARS-CoV-2 Specific CD4(+) and CD8 (+) T Cell Responses Using MHC Class I and II Tetramers

Yuri Poluektov; Pirouz Daftarian; Marc C. Delcommenne

doi:10.1101/2020.07.08.194209

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bioRxiv · 10.1101/2020.07.08.194209

Assessment of SARS-CoV-2 Specific CD4(+) and CD8 (+) T Cell Responses Using MHC Class I and II Tetramers

Yuri Poluektov·Pirouz Daftarian·Marc C. Delcommenne

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Abstract

The success of SARS-CoV-2 (CoV-2) vaccines is measured by their ability to mount immune memory responses that are long-lasting. To achieve this goal, it is important to identify surrogates of immune protection, namely, CoV-2 MHC Class I and II immunodominant pieces/epitopes and methodologies to measure them. Here, we present results of flow cytometry-based MHC Class I and II QuickSwitch platforms for assessing SARS-CoV-2 peptide binding affinities to various human alleles as well as the H-2 Kb mouse allele. Multiple SARS-CoV-2 potential MHC binders were screened and validated by QuickSwitch testing. While several predicted peptides with acceptable theoretical Kd showed poor MHC occupancies, fourteen MHC class II and a few MHC class I peptides showed promiscuity in that they bind with multiple MHC molecule types. With the peptide exchange generated MHC tetramers, scientists can assess CD4+ and CD8+ immune responses to these different MHC/peptide complexes. Results obtained with several SARS-CoV-2 MHC class I and II peptides are included and discussed.

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Yuri Poluektov, Pirouz Daftarian, Marc C. Delcommenne. 2020-07-09. Assessment of SARS-CoV-2 Specific CD4(+) and CD8 (+) T Cell Responses Using MHC Class I and II Tetramers. https://doi.org/10.1101/2020.07.08.194209

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