The dysfunction of effector T-cells in MPE/MA has been reported in previous studies.5,18,24 As HER2.28ζ CAR-T cells exhibited superior anti-tumor cytotoxicity than HER2.BBζ CAR-T cells, we next investigated the cytotoxicity of HER2.28ζ CAR-T cells that cultured in different components of MPE/MA samples from clinical patients (Supplementary Table. Here, ERBB2 is linked to neoplasm.