IL7 and neoplasm: In a co-culture system, the cytotoxicity of B7–H3 CAR-T/IL-7 against chordoma cells was greater than that of B7–H3 CAR-T cells over time and, confirming the positive effect of Il-7, sustained tumor cytotoxicity by B7–H3 CAR-T/IL-7 cells decreased after addition of anti-IL-7 antibodies into the system.