FCGR2A and leukemia: To evaluate target selectivity, next the viability of non-CSPG4 expressing cells was investigated towards anti-CSPG4-(PDD) ADC, isotype-(PDD) ADC, naked anti-CSPG4 antibody and the PDD payload alone in FcγR-high monocytic U937 and the basophilic leukemia RBL-SX-38 cells (Figure 5B).