Fig. 4

The frequency of ILT2⁺CD57⁺ CD56⁺ Dim NK-cells are significantly associated with both A/H3N2 vaccine antibody responses and pre-vaccination plasma IL-6 levels in older adults from the follow-up cohort (n = 63). A 4-week antibody responses were regressed on the frequency of positivity for different CD56⁺ Dim and CD56⁺⁺ Bright NK-cell phenotypic markers and adjusted coefficients for each marker are shown. B Phenotype marker positivity was regressed on TNF or IL-6 and adjusted coefficients for each mediator are shown. C The geometric mean of the frequency of ILT2⁻CD57⁺, ILT2⁺CD57⁺ and ILT2⁺CD57.⁻ Dim NK-cells are shown, and overlayed on a representative participant dot plot. D Coefficients for each ILT2/CD57 subset relative to antibody titres (upper), and inflammatory mediators relative to subset frequency (lower) are shown. For A, B and D: antibody titres, inflammatory mediator levels and phenotype marker positivity were standardized and natural-log transformed to facilitate cross-comparison. Further, each phenotypic marker and inflammatory mediator were run in separate models, and the effect size and significance of coefficients for each fixed effect of interest (ie. marker or inflammatory mediator) are indicated by colour and asterisk (***, p < 0.001; **, p < 0.001; *, p < 0.05), respectively