Figure 4

Ex vivo binding of non-fucosylated anti-CD20 IgG1 rituximab to FcγRIIIa on NK cells. Heparinized peripheral blood from donor 4 was incubated with non-fucosylated anti-CD20 IgG1 10 μg/mL (blank histogram) or stain buffer alone (filled histogram), in the presence of anti-CD16 antibody 3G8 (bold line) or mouse IgG1 isotype control (solid line). CD3^-CD56⁺ NK cells were gated in the histogram. The binding of non-fucosylated anti-CD20 IgG1 to FcγRIIIa on NK cells was detected by anti-rituximab-FITC.