Figure 1

Antigen binding activity of anti-CD20 IgG1 rituximab variants to target B cells. Purified human B cells from healthy donor 1 were incubated with anti-CD20 IgG1 rituximab (open square) and its variants (fucosylated (closed circle), non-fucosylated (open circle), triple amino acid-substituted mutant S239D/S298A/I332E (closed square)) at indicated concentrations at 37°C for 30 min (a), or at 3.3 μg/mL at 37°C for 30, 120 and 240 minutes (b). In both experiments, anti-CD20s bound to CD20 on B cells were detected with PE-conjugated mouse anti-human IgG. Mean fluorescence intensity is indicated by mean values ± SD of triplicates.