Dataset Information

Rapid, scalable assessment of SARS-CoV-2 cellular immunity by whole-blood PCR.

ABSTRACT: Fast, high-throughput methods for measuring the level and duration of protective immune responses to SARS-CoV-2 are needed to anticipate the risk of breakthrough infections. Here we report the development of two quantitative PCR assays for SARS-CoV-2-specific T cell activation. The assays are rapid, internally normalized and probe-based: qTACT requires RNA extraction and dqTACT avoids sample preparation steps. Both assays rely on the quantification of CXCL10 messenger RNA, a chemokine whose expression is strongly correlated with activation of antigen-specific T cells. On restimulation of whole-blood cells with SARS-CoV-2 viral antigens, viral-specific T cells secrete IFN-γ, which stimulates monocytes to produce CXCL10. CXCL10 mRNA can thus serve as a proxy to quantify cellular immunity. Our assays may allow large-scale monitoring of the magnitude and duration of functional T cell immunity to SARS-CoV-2, thus helping to prioritize revaccination strategies in vulnerable populations.

SUBMITTER: Schwarz M

PROVIDER: S-EPMC10603792 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Rapid, scalable assessment of SARS-CoV-2 cellular immunity by whole-blood PCR.

Schwarz Megan M Torre Denis D Lozano-Ojalvo Daniel D Tan Anthony T AT Tabaglio Tommaso T Mzoughi Slim S Sanchez-Tarjuelo Rodrigo R Le Bert Nina N Lim Joey Ming Er JME Hatem Sandra S Tuballes Kevin K Camara Carmen C Lopez-Granados Eduardo E Paz-Artal Estela E Correa-Rocha Rafael R Ortiz Alberto A Lopez-Hoyos Marcos M Portoles Jose J Cervera Isabel I Gonzalez-Perez Maria M Bodega-Mayor Irene I Conde Patricia P Oteo-Iglesias Jesús J Borobia Alberto M AM Carcas Antonio J AJ Frías Jesús J Belda-Iniesta Cristóbal C Ho Jessica S Y JSY Nunez Kemuel K Hekmaty Saboor S Mohammed Kevin K Marsiglia William M WM Carreño Juan Manuel JM Dar Arvin C AC Berin Cecilia C Nicoletti Giuseppe G Della Noce Isabella I Colombo Lorenzo L Lapucci Cristina C Santoro Graziano G Ferrari Maurizio M Nie Kai K Patel Manishkumar M Barcessat Vanessa V Gnjatic Sacha S Harris Jocelyn J Sebra Robert R Merad Miriam M Krammer Florian F Kim-Schulze Seunghee S Marazzi Ivan I Bertoletti Antonio A Ochando Jordi J Guccione Ernesto E

Nature biotechnology 20220613 11

Fast, high-throughput methods for measuring the level and duration of protective immune responses to SARS-CoV-2 are needed to anticipate the risk of breakthrough infections. Here we report the development of two quantitative PCR assays for SARS-CoV-2-specific T cell activation. The assays are rapid, internally normalized and probe-based: qTACT requires RNA extraction and dqTACT avoids sample preparation steps. Both assays rely on the quantification of CXCL10 messenger RNA, a chemokine whose expr ...[more]

PMID: 35697804

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Dataset Information

Rapid, scalable assessment of SARS-CoV-2 cellular immunity by whole-blood PCR.

Publications

Rapid, scalable assessment of SARS-CoV-2 cellular immunity by whole-blood PCR.

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