HLA-A and COVID-19: Subsequently, we tested whether the selected peptides represent SARS-CoV-2-specific CD8 + T cell epitopes by incubating PBMCs from the convalescent, immunosuppressed COVID-19 patient on day 233 or from immunocompetent, convalescent, HLA-A*02:01/HLA-A*03:01 positive COVID-19 patients with the peptides for 14 days.