IFNG and cancer: In comparison, 100% of healthy individuals (12 of 12) showed an enhanced frequency of Delta spike-specific IFNγ-secreting T cells at visit 2 compared to prevaccination visit 1, and their median responses to S1 and S2 spike peptides at visit 2 were 4.6- and 2.2-fold higher than those observed in individuals with cancer (Fig. 4a,c).