CHMP5 and infection: After vaccination or infection, most patients develop T cell responses to multiple epitopes across different regions of the spike peptide.67–69 This observation suggests that the T cell response is less likely to be affected by amino acid mutations in novel viral variants.69 We showed that T cells from 31/59 donors were able to recognize the mutated peptides in the B.1.617.2 variant, despite immunization with a vaccine expressing the WT spike protein.