IFNG and COVID-19: In order to determine frequencies of SARS-CoV-2-specific T cells in COVID-19 patients, PBMCs were stimulated with peptide pools derived from the SARS-CoV-2-endoded proteins spike (S), membrane protein (M), and nucleocapsid protein (N) before the percentages of cells producing TNFα, IL-2, and IFNγ was determined.