Differential regulation patterns of anti-CD20 mAbs in MCL

We investigated the differential regulation patterns of type I anti-CD20 monoclonal antibody (mAb) rituximab and type II obinutuzumab on a transcriptional level. Using a panel of MCL cell lines, we determined the effects of obinutuzumab and rituximab as monotherapies as well as in combination on cell viability and proliferation. Obinutuzumab induced a higher reduction in cell proliferation in each mantle cell lymphoma cell line than rituximab did. Results indicate a common pattern of expression changes after binding of anti-CD20 mAbs, but also reveal a significant difference between type I and type II treatment. Combination treatment resulted in a rituximab-like expression pattern. Many deregulated genes were associated with stress signalling, cell death, immune response and other functional clusters. Our analyses identified different and antibody-specific downstream expression patterns of obinutuzumab and rituximab, which may represent the molecular basis of the superior effect of obinutuzumab in comparison to rituximab. 25 samples with 3 replicates each