The SARS-CoV-2 T Cell Analysis Kit (PBMC), human, has been developed for the fast and easy detection of SARS-CoV-2-reactive T cells by intra- and extracellular staining of activation markers and cytokines. The use of 96-well cell culture plates enables the processing and analysis of multiple samples in parallel. The kit contains a SARS-CoV-2 PepTivator® Peptide Pool of choice (see different kit variants), antibodies for the identification of CD4⁺ and CD8⁺ T cells, the exclusion of monocytes and B cells as well as the staining of activation markers and cytokines. Furthermore a positive control (CytoStim™), a live/dead marker (Viobility™ 405/452 Fixable Dye), Brefeldin A and reagents (Inside Fix and Inside Perm) for the fixation and permeabilization of cells after stimulation are included. The optimized flow panel and protocol ensure a comprehensive and efficient analysis of SARS-CoV-2-reactive T cells.

T lymphocytes execute and control immunological reactions with a repertoire of cytokines, cytotoxic substances, and other mediators. The quantitative and qualitative analysis of CD4⁺ T cells and CD8⁺ T cells specifically recognizing and reacting towards a defined antigen provide important information to understand their function in various immunological situations. The presence of these cells indicate an infected or convalescent donor and may also allow conclusions on disease progress, severity, specific immune reaction and status^1-8. Antigen-reactive T cells can thereby be identified and characterized by analyzing their effector function, e.g. upregulation of activation markers and production of cytokines. In the context of COVID-19, the SARS-CoV-2 T cell Analysis kit (PBMC), human, represents a sensitive and precise multiparameter assay to efficiently asses the SARS-CoV-2-reactive T cell response.

The use of 96-well cell culture plates enables the analysis of multiple samples in parallel. The kit contains a SARS-CoV-2 PepTivator® Peptide Pool of choice, antibodies for the identification of CD4⁺ and CD8⁺ T cells, the exclusion of monocytes and B cells as well as the staining of activation markers and cytokines. Furthermore a positive control (CytoStim™), a live/dead marker (Viobility™ 405/452 Fixable Dye), Brefeldin A and reagents (Inside Fix and Inside Perm) for the fixation and permeabilization of cells after stimulation are included. The optimized flow panel and protocol ensure a comprehensive and efficient analysis of SARS-CoV-2-reactive T cells in the context of: 

• Rapid detection of CD4⁺ and CD8⁺ SARS-CoV-2-reactive T cells
• Phenotypical characterization of activated T cells after stimulation with  SARS-CoV-2 PepTivator® Peptide Pools by flow cytometry
• Immunomonitoring of SARS-CoV-2-reactive T cells
• Research and monitoring of infection- and vaccine-specific T cell responses in individuals

1. Swadling, L., et al. (2020) T cells in COVID-19 — united in diversity. Nat. Immunol. 21: 1307-1308 
2. Jarjour, N. N., et al. (2021) T Cell Memory: Understanding COVID-19. Immunity Primer 54: 14-18 
3. Thieme, C. .J. et al. (2020) Robust T cell response toward spike, membrane, and nucleocapsid SARS-CoV-2 proteins is not associated with recovery in critical COVID-19 patients. Cell Rep. Med. 1: 100092 
4. Kusnadi, A. et al. (2021) Severely ill COVID-19 patients display impaired exhaustion features in SARS-CoV-2-reactive CD8 + T cells. Sci. Immunol. 6: eabe4782. (2021)
5. Meckiff, B. J. et. al. (2020) Imbalance of regulatory and cytotoxic SARS-CoV-2-reactive CD4+ T cells in COVID-19. Cell 183: 1340-1353
6. Braun, J. et al. (2020) SARS-CoV-2-reactive T cells in healthy donors and patients with COVID-19. Nature 587: 270-274
7. Bacher, P. et al. (2020) Low avidity CD4+ T cell responses to SARS-CoV-2 in unexposed individuals and humans with severe COVID-19. Immunity 53: 1258-1271
8. Dan, J. M. et al. (2021) Immunological memory to SARS-CoV-2 assessed for up to 8 months after infection. Science 371: eabf4063.