CD274 and neoplasm: MB2033 efficiently bound to hPD-L1 high-expressing MDA-MB-231 cells (Fig. 2c) but not to hPD-L1 low-expressing HEK293T cells (Fig. 2d), confirming that MB2033 can induce a response dependent on the expression of PD-L1 on cells and would have tumor-targeting function.