FIG 3.

Assessment of direct and antibody-dependent NK cell activation using flow cytometry. NK cell activation is measured as the percentage of CD3⁻ CD56^dim NK cells that express the degranulation marker CD107a and/or IFN-γ. (A) Gating on IFN-γ⁺ and/or CD107a⁺ NK cells in a representative donor. (B) The graph depicts NK cell activation in unstimulated NK cells (“PBMC only” and “PBMC+CEM”) and stimulated NK cells (“Ab-Dependent Activation” [PBMC + CEM + HIVIG] and “Direct Activation” [PBMC + 721.221]). Lines indicate medians. (C) The graphs show the percentages of activated NK cells within the educated and noneducated populations following direct and antibody-dependent stimulation. Educated and noneducated data were compared using the Wilcoxon matched-pairs test. A P value of <0.05 was considered significant.