In terms of relationships between clinical outcomes and disease severity, previous studies have suggested an association between the magnitude of CD4 T cell responses in less severe disease [8,9,23,24], but these were limited by the number of acute COVID-19 subjects available for analysis (Mele et al., n = 55; Rydyznski Moderbacher et al., 2020 n = 24; Tan et al., 2021 n = 12; Oja et al., n = 56). The gene discussed is CD4; the disease is COVID-19.