In vivo, these anti-GPC3/IL15 CAR-Vδ1 T cells were primarily found in the tumor tissue by day 7, and showed limited presence in the blood, bone marrow, spleen or lungs, indicating better tumor-specific targeting compared to anti-GPC3 CAR-αβ T cells, which could be detected in all the mentioned compartments most likely due to xenoantigen reactivity and may therefore have a higher potential for causing GvHD [238]. Here, GPC3 is linked to graft versus host disease.