CEACAM1 and neoplasm: Consistently, the levels of cytokines from 19BBz CAR-T cells stimulated with parent tumor cells or CEACAM1 overexpressing tumor cells were similar, while the T3/28 CAR-T cells secreted higher levels of cytokines when co-cultured with CEACAM1 overexpressing tumor cells compared with parent tumor cells (figure 2B).