Patients with COVID-19 had significantly higher levels of M0 macrophages (p-value 3.63x10-06), plasma cells (p-value 5.05x10-04), cytotoxic CD8+ T cells (p-value 4.58x10-03), regulatory T cells (p-value 7.30x10-03) and resting natural killer cell (p-value 8.90x10-03). This evidence concerns the gene CD8A and COVID-19.