Figure 4. SEMA7A expression is associated with IFN-γ production by NK cells.

(A) Representative flow cytometry plots depicting co-expression of SEMA7A and IFN-γ (left) or CD107a (right) on bulk NK cells after overnight culture of PBMCs in medium alone or in the presence of 5 μg/mL PHA, K562 cells at 10:1 E:T ratio, 20 ng/mL IL-12 + 10 ng/mL IL18 + 1 ng/mL IL15, 100 U/mL IL-2, or 2.8 μg/mL CMV pp65 native protein. (B) Each data point represents proportions of IFN-γ^pos (left panel) or CD107a^pos (right panel) SEMA7A^pos CD56^bright (black circles) and CD56^dim (grey squares) NK cells following overnight incubation with indicated stimuli after subtracting background (unstimulated). Bar indicates the median. Asterisks indicate significant differences in proportions of IFN-γ^pos NK cells that are positive for SEMA7A between CD56^bright and CD56^dim NK cells. * p<0.05. Pound signs indicate differences in IFN-γ production upon stimulation compared to unstimulated. ^## p<0.01. Significance determined by Wilcoxon matched-pairs signed rank test. Data are shown for n=6 donors and pooled from 2 independent experiments. (C) Spearman correlation of frequencies of SEMA7A^pos and IFN-γ^pos CD56^bright (left panel) or CD56^dim (right panel) activated NK cells.