CD27 and infection: Upon further analysis of CD8+ T cell responses, distinct TBEV epitopes and phenotypes have been recognised [111], typically active against TBEV NSPs (NSP1, NSP5), indeed temporal changes in the CD8+ T cell phenotype during TBE infection has been observed from CD45RA-CCR7-CD27+CD57- at day 7 infection to CD45RA-CCR7-CD27+CD57+ at day 21 infection [112].