Proposed mechanism of mAb-induced PCD. Schematic diagram illustrating the proposed sequence of events in the proposed cell death pathway evoked by type II anti-CD20 and anti-HLA DR mAb. mAb ligation results in HA and actin reorganization followed by lysosomal membrane permeabilization, release of cathepsins, and generation of ROS via NAPDH oxidase which ultimately culminates in nonapoptotic cell death.