Figure 2. . CD19+ CLL B cells before and after obinutumab. Wilcoxon signed rank test: leukemic burden destruction after the first dose of obinutuzumab depends on natural killer-antibody-dependent cytotoxicity (log scale).

In CLL, type 2 anti-CD20 monoclonal antibody therapy such as obinutuzumab administered intravenously encounters and interacts with both effector cells (natural killer cells) and target cells (leukemia cells) in the blood. This figure represents the effect of obinutuzumab on target cells (CLL B cells). Note that this effect is induced by antibody-dependent cytotoxicity of effector cells (natural killer cells) redirected by obinutuzumab. Baseline target cells (45,152 CLL B cells/μl) and post-treatment target cells are represented (22,736 CLL B cells/μl).

CLL: Chronic lymphocytic leukemia.