CD34 and neoplasm: Following a 20 h co-incubation of CAR T and CD34+ HSCs at an E:T ratio of 20, conditions which result in maximal CAR T cytotoxicity against CD33+ tumor lines (Figure 4), whole cell suspensions were seeded in semi-solid methylcellulose-based media for 14 days, in order to elicit differentiation of the surviving target cells into different hematopoietic cell types (Figure 7).