The therapeutic activity of anthracyclines and tumor colonization of Tc1 depend upon Vγ4 Vγ6 γδ T cells. (A) WT, TCR δ^−/−, or Vγ4/6^−/− mice with established MCA205 tumors were injected intratumorally with PBS or DX. Tumor size was measured at the indicated time and plotted as mean ± SEM (n = 8/group). (B) Percentage of IL-17A– or IFN-γ–expressing cells within CD3⁺ TCRδ⁺ and CD3⁺ CD8⁺ TILs, respectively, in WT or Vγ4/6^−/− mice. A typical dot plot is shown (left) and statistical analysis was performed with combined data from two independent experiments (right). *, P < 0.05; ***, P < 0.001.