Ptpn2fl/fl, Lck-Cre;Ptpn2fl/fl, or Lck-Cre;Ptpn2fl/fl;Lck+/- HER-2 CAR-T cells were incubated with 24JK-HER-2 or 24JK sarcoma cells and the proportion of CD8+IFNγ+ versus CD8+IFNγ+TNF+ CAR-T cells determined by flow cytometry. 