We also observed a higher number of CD8+ and CD4+ cells in tissue slices treated with FOLR1 CAR-T cells despite starting with the same number of total cells, indicating either a reduced survival of UTD T cells in the tumor tissue slices compared to FOLR1 CAR-T cells or an increased persistence of FOLR1 CAR-T cells compared to UTD T cells. The gene discussed is CD4; the disease is neoplasm.