CD28 and neoplasm: After co-incubation with tumor cells, the CD28 group showed a decreased CD39 expression for F8-FR4.V and Dual.V CAR T cells (16% ± 1% for both), while CD276.V-CARs remained at higher levels of 22% ± 5% when co-incubated with Rh4 and of 21% ± 5% when co-incubated with JR.