Ptpn2fl/fl, Lck-Cre;Ptpn2fl/fl or Lck-Cre;Ptpn2fl/fl;Lck+/- HER-2 CAR-T cells were incubated with 5 μM CTV-labelled (CTVbright) 24JK-HER-2 and 0.5 μM CTV-labelled (CTVdim) 24JK sarcoma cells. Antigen-specific target cell lysis was monitored for the depletion of CTVbright 24JK-HER-2 cells by flow cytometry. 