Then we adoptively co-transferred Her2-CAR-T cells carrying G5-CD56 or SrtA-CD56 into SKOV3-bearing NSG mice, followed by LIPSTIC labeling at 72 h later (Fig. 4g), and found that LIPSTIC labeling was on the tumor-infiltrated G5-CD56-I-CAR T cells, while not on the G5-CD56mut-I-CAR T cells, which directly confirmed the CD56-CD56 intermolecular interaction between CAR-T cells in vivo (Fig. 4h). The gene discussed is NCAM1; the disease is neoplasm.