The binding of the peptide on T2A2 was measured with anti-HLA-A2 staining with flow cytometry. provides information that contributes to the understanding of SARS-CoV-2-specific CD8+ T?cell responses elicited by contamination of mutated strains or vaccination. genus of the Coronoviridae family, and this single-stranded positive-sensed RNA computer virus bears 11 protein-coding genes, including 4 for structural proteins: spike (S), envelope (E), membrane (M), nucleocapsid (N), and 7 for nonstructural proteins: open reading frame (ORF) 1ab, ORF 3a, ORF PROML1 6, ORF 7a, ORF 7b, ORF 8, and ORF 10 (Wu et?al., 2020). Its believed that this viral clearance in SARS-CoV-2 infected individuals is mainly dependent on host immune system, especially adaptive immunity (Zhang et?al., 2020). Specific antibodies have been PG 01 observed in computer virus infected individuals and convalescent COVID-19 patients, with S and N being the major viral proteins to elicit antibody production (Wheatley et?al., 2021). S protein bears the binding site to ACE 2 (ACE2) receptors on host cells and is crucial for viral contamination. So the neutralizing antibodies against S protein are believed to play an important role for the computer virus clearance (Bertoglio et?al., 2021). However, a couple of studies have shown that antibody titers decline fast in some convalescent patients (Seow et?al., 2020; Ward et?al., 2020). On the other hand, current studies have demonstrated that specific T?cell responses emerge in most of the COVID-19 patients during the early stage of the contamination (Ferreras et?al., 2021). Although significant reduction in T?cell counts was observed in severe COVID-19 patients, the revealed antigen specific T?cell response indicated their important role in resolving SARS-CoV-2 contamination (Grifoni et?al., 2020; Le Bert et?al., 2020; Weiskopf et?al., 2020). Furthermore, SARS-CoV-2 specific CD8+ T?cells PG 01 have been detected in convalescent COVID-19 patients (Braun et?al., 2020; Grifoni et?al., 2020; Gangaev et?al., 2021) and SARS-CoV-2 vaccinees (Jackson et?al., 2020). Recent studies have shown that specific CD8+ epitopes to SARS-CoV-2 are mainly located in ORF1ab, N protein, S protein, ORF 3, M protein, and ORF 8 (Ferretti et?al., 2020; Grifoni et?al., 2020), and the identification of these epitopes will provide the basis for next-generation vaccine development and better understanding of CD8+ T?cell immunity. With the ongoing distributing of the computer virus all over the world, the genetic development in SARS-CoV-2 continues to provide the opportunities for the computer virus to obtain mutations which might contribute to the changes in viral transmissibility, infectivity, pathogenesis, and even immune evasion (Neches et?al., 2021; Rashid et?al., 2021). The D614G spike variant emerged in March 2020 was the earliest evidence of adaptive evolution of the computer virus in humans, which resulted in increased infectivity of the computer virus PG 01 (Yurkovetskiy et?al., 2020). Recently, a newer variant termed B.1.1.7 (also called VUI202012/01) was spreading rapidly in the United Kingdom (UK) and raised great issues (Davies et?al., 2021; Kirby, 2021). This variant contains 17 non-synonymous mutations in ORF1ab, S protein, ORF8 and N proteins, some of which are of particular issues, such as the D614G mutation and eight additional mutations in S protein: H69-70, Y144, N501Y, A570D, P681H, T716I, S982A, and D1118H (Davies et?al., 2021). For example, N501Y is located in the receptor binding motif (RBM) and P681H is usually proximal to the furin cleavage site (Peacock et?al., 2020; Starr et?al., 2020). H69-70 in S protein has developed in other lineages of SARS-CoV-2, which enhances viral infectivity and is linked to immune escape in immunocompromised patients (Kemp et?al., 2020a, 2020b). There is strong evidence that variant B.1.1.7 is spreading substantially.