However, the details of response following SARS-CoV-2 vaccination in subjects with such pre-existing memory T cells are incompletely understood, and questions remain about the possibility of enhanced T-cell response to other immunodominant epitopes, as CD8 T cells of COVID-19 patients recognize other epitopes in SARS-CoV-2 that reside outside the S protein. Here, CD8A is linked to COVID-19.