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.
【초록키워드】 SARS-CoV-2, Immunity, CXCL10, risk, chemokine, monocyte, RNA extraction, T cell, Antigen-specific T cells, cellular immunity, mRNA, breakthrough infections, antigens, quantification, expression, quantitative PCR, IFN-γ, T cell activation, Messenger RNA, Activation, protective immune response, revaccination, helping, populations, Cell, SARS-CoV-2 viral, functional, correlated, magnitude, stimulate, normalized, secrete, 【제목키워드】 SARS-CoV-2, PCR, cellular immunity, Rapid,