Figure 2.

Blood NK cell cytotoxicity in NSCLC patients.

PBMCs from patients and HD were cultured with K562 cells for 6 hours at a ratio E:T of 1:1. (A) Degranulation of total NK cells among PBMCs was assessed by flow cytometry: percentages of total NK cells expressing CD107a (right panel) and Granzyme B (left panel) in HD (n = 10) and NSCLC patients (n = 10), Mann-Whitney test (ns = not significant; ** P < 0.01). Spontaneous (open circles) and K562-activated (solid circles) values are indicated, paired t-test (* P < 0.05; ** P < 0.01; **** P < 0.0001). (B) Percentages of K562 cell death represented by rates of annexin V⁺ 7-AAD⁺ and annexin V⁺ 7-AAD⁻ K562 cells, after 6 hours of interactions with PBMCs from HD (n = 10) and NSCLC patients (n = 10), Mann-Whitney test (ns = not significant). Columns, mean of rates; bars, SEM. On the left panels, (C) degranulation and (D) Granzyme B production by NK cell subsets in response to K562 stimulation of a representative patient are showed. The percentages indicate the rate of CD107a⁺ and Granzyme B⁺ NK cells after gating on CD56^dim CD16⁺, CD56^dim CD16⁻ or CD56^bright cells. On the right panels, are summarized rates of (C) CD107a⁺ and (D) Granzyme B⁺ among CD56^dim CD16⁺, CD56^dim CD16⁻ and CD56^bright NK cell subsets of either both HD (grey n = 10) and patients (black n = 10), Mann-Whitney test (ns = not significant; * P < 0.05; *** P < 0.001; **** P < 0.0001), or only patients (black n = 10), Friedman test (ns = not significant; * P < 0.05; *** P < 0.001; **** P < 0.0001). Red bars represent the mean of each group.