TIV. CD4+ T cells were labeled with CFSE and then cultured with whole virus A/NC/99 (H1N1), A/WI/05 (H3N2) or BM/04. The fold increase in proliferation after vaccination was calculated by determining the ratio of the day 28:day 0 proliferative index (ratio of percent CFSEdim cells stimulated with influenza:% CFSEdim cells in wells without antigen). The fold increase for each individual in the group is shown together with 95% confidence intervals for each group. The proliferative response for H1N1-stimulated cultures was significantly different between LAIV and TIV groups (p=0.02, Mann-Whitney), but not for H3N2 or B groups (p=0.07 and 0.33, respectively).
