Large-Scale Identification of T-Cell Epitopes Derived From Severe Acute Respiratory Syndrome Coronavirus 2 for the Development of Peptide Vaccines Against Coronavirus Disease 2019.
BACKGROUND
Coronavirus disease 2019 (COVID-19) continues to be a major public health challenge globally. The identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-derived T-cell epitopes is of critical importance for peptide vaccines or diagnostic tools of COVID-19.


METHODS
In this study, several SARS-CoV-2-derived human leukocyte antigen (HLA)-I binding peptides were predicted by NetMHCpan-4.1 and selected by Popcover to achieve pancoverage of the Chinese population. The top 5 ranked peptides derived from each protein of SARS-CoV-2 were then evaluated using peripheral blood mononuclear cells from unexposed individuals (negative for SARS-CoV-2 immunoglobulin G).


RESULTS
Seven epitopes derived from 4 SARS-CoV-2 proteins were identified. It is interesting to note that most (5 of 7) of the SARS-CoV-2-derived peptides with predicted affinities for HLA-I molecules were identified as HLA-II-restricted epitopes and induced CD4+ T cell-dependent responses. These results complete missing pieces of pre-existing SARS-CoV-2-specific T cells and suggest that pre-existing T cells targeting all SARS-CoV-2-encoded proteins can be discovered in unexposed populations.


CONCLUSIONS
In summary, in the current study, we present an alternative and effective strategy for the identification of T-cell epitopes of SARS-CoV-2 in healthy subjects, which may indicate an important role in the development of peptide vaccines for COVID-19.
['Ma|Yipeng|Y|', 'Liu|Fenglan|F|', 'Lin|Tong|T|', 'Chen|Lei|L|', 'Jiang|Aixin|A|', 'Tian|Geng|G|', 'Nielsen|Morten|M|0000-0001-7885-4311', 'Wang|Mingjun|M|']
D015496:CD4-Positive T-Lymphocytes D018414:CD8-Positive T-Lymphocytes D000086382:COVID-19 D000086663:COVID-19 Vaccines D002460:Cell Line D018984:Epitopes, T-Lymphocyte D006801:Humans D007963:Leukocytes, Mononuclear D000086402:SARS-CoV-2 D022223:Vaccines, Subunit
T-cell epitopes 2 CoV SARS existing T cells pre uninfected individuals