Figure 3.

Modulation of NK subpopulations by multiple doses of the BNT162b1 vaccine. (A) Summary results indicating different NK cell subsets are shown as percentages (medians) in the left panel and as absolute numbers in the right panel. Individuals who had never been SARS-CoV-2-infected and received three doses of the BNT162b1 mRNA vaccine were analyzed at different time points: baseline (immediately before the first inoculation (white triangle) (T0), 7 (T1) and 21 (T2) days after initial inoculation, one (T3), three (T4) and six (T5) months after the first vaccine booster (grey triangle), and, finally, ten days after the second vaccine booster (black triangle) (T6). Boxes stretch from the 25th to the 75th percentile. Lines across the boxes indicate the median values. Lines stretching from the boxes indicate extreme values. Statistical significance is shown; **p<0,05. (B) Gate strategy used to identify NK cell subsets. (a) Lymphocyte selected by forward (FS) and side scatter (SS) properties (Gate Lymphocyte). (b) The CD3+CD19+ vs. the SS dot plot allows the discrimination of T and B lymphocytes (Gate J); the remaining double negative cells (Gate CD3-CD19-) were analyzed within a CD56 vs. CD16 dot plot (c) leading to the identification of NK cells (Gate Natural Killer). (d) NK subsets were defined in the CD56 vs CD16 dot plot as: CD56^brightCD16− (1), CD56^dimCD16− (2), CD56^dimCD16^dim (3), CD56^dimCD16^bright (4), and CD56−CD16^bright (5).