UK Variant and Immune Evasion
The B.1.1.7 variant contains the E484K mutation which renders resistance to serologic responses in infected individuals8.To determine if this VOC evaded T-cell immunity, we analyzed 19 infected/recovered patients and 18 vaccinated individuals for CD4+/CD8+ T-cell responses against B.1.1.7 variant Spike protein. As shown in Figure 3, there is no significant reduction in CD4+/CD8+ T-cell responses to the variant B.1.1.7 Spike peptides as compared to the original Wuhan Spike peptides (mean of infected patients: 0.23% original to 0.18% variant; mean of vaccinated individuals: 0.16% original to 0.14% variant). Five of 20 infected patients and 6 of 18 vaccinated individuals had no detectable CD8+ T-cells against the original or variant Spike peptides (data not shown). The other 15 infected and 12 vaccinated individuals demonstrated nearly identical CD8+ responses to the original Wuhan Spike and variant Spike (Figure 3B). When the individual T-cell responses to the original and variant spikes were compared, those with higher CD4+ T-cell immunity tend to lose some reactivity to the variant peptide, but not at a significant level (Figure 3C and 3D). In summary, T-cell memory induced by SARS-CoV-2 infection or vaccination establishes effective immune response against the B.1.1.7 variant. This would suggest protective immunity against B.1.1.7 infection and possibly other VOC13.