SARS-CoV-2 infection takes a mild or clinically inapparent course in the majority of humans who contract this virus. After such individuals have cleared the virus, only the detection of SARS-CoV-2-specific immunological memory can reveal the exposure, and hopefully the establishment of immune protection. With most viral infections, the presence of specific serum antibodies has provided a reliable biomarker for the exposure to the virus of interest. SARS-CoV-2 infection, however, does not reliably induce a durable antibody response, especially in sub-clinically infected individuals. Consequently, it is plausible for a recently infected individual to yield a false negative result within only a few months after exposure. Immunodiagnostic attention has therefore shifted to studies of specific T cell memory to SARS-CoV-2. Most reports published so far agree that a T cell response is engaged during SARS-CoV-2 infection, but they also state that in 20-81% of SARS-CoV-2-unexposed individuals, T cells respond to SARS-CoV-2 antigens (mega peptide pools), allegedly due to T cell cross-reactivity with Common Cold coronaviruses (CCC), or other antigens. Here we show that, by introducing irrelevant mega peptide pools as negative controls to account for chance cross-reactivity, and by establishing the antigen dose-response characteristic of the T cells, one can clearly discern between cognate T cell memory induced by SARS-CoV-2 infection vs. cross-reactive T cell responses in individuals who have not been infected with SARS-CoV-2.
【저자키워드】 COVID-19, Immune monitoring, ELISPOT, mega peptide pools, ImmunoSpot, T cell affinity, 【초록키워드】 SARS-CoV-2, coronavirus, Biomarker, T cells, SARS-COV-2 infection, Antibody Response, Human, peptide, virus, Immunological memory, viral infections, Antigen, cross-reactivity, T cell, Viral, Mild, antigens, serum antibody, common cold, SARS-CoV-2 antigen, characteristic, T cell response, immune protection, SARS-CoV-2 antigens, False negative, Cold, cross-reactive, exposure to, specific serum, negative controls, infected individual, infected individuals, individual, serum antibodies, common cold Coronaviruses, peptide pools, T cell memory, MOST, negative control, common, Course, clinically, provided, majority, induce, individuals, respond, infected with SARS-CoV-2, peptide pool, 【제목키워드】 T cell, response, chance, Cognate,