Figure 3.

Functional differences characterize NK cells isolated from normal and low responders. Functional flow cytometric analysis of frozen PBMCs isolated from vaccinated individuals classified into normal and low responders. Frequencies of (a) CD107a⁺CD56^dim and (b) IFNγ⁺CD56^dim NK cells with regard to CD16 expression (CD16⁻ white/CD16⁺ black). Ratio of CD107a-expressing (c) CD57⁻NKG2C⁺, (d) CD57⁺NKG2C⁺ and (e) CD57⁺NKG2C⁻ CD56^dimCD16⁺ NK cells isolated from responders and non-responders on the indicated days post- and pre-vaccination (day 0) depicted as scatter plots with bars indicating the mean with 95% confidence interval. (f) Frequency of CD56^dimCD16⁺ NK cells expressing CD107a (red solid), NKG2C⁺CD57⁻ (black solid), NKG2C⁺CD57⁺ (green), NKG2C⁻CD57⁺ (black dashed) shown for individual responders and (g) non-responders. Asterisks denote significant values as calculated by unpaired and non-parametric Mann–Whitney test. * p ≤ 0.05, ** p ≤ 0.01.