CD4 and COVID-19: Higher numbers of CD4 and CD8 T-cells, specific for SARS-CoV-2 spike- (S) or nucleocapsid (N) protein peptide-pools, were detected in peripheral blood of the patient compared to a seropositive individual that had tested PCR positive for SARS-CoV-2 with moderate COVID-19 and seropositive CC-plasma donors with mild COVID-19 (Fig. 2B).