HER-2-specific Ptpn2fl/fl, Lck-Cre;Ptpn2fl/fl and Lck-Cre;Ptpn2fl/fl;Lck+/- CAR-T cells were incubated with plate-bound α-CD3 and CD25 MFIs on CD8+CD44hiCD62Llo versus CD8+CD44hiCD62Lhi CAR-T cells determined by flow cytometry. 