Figure 5. Adoptively transferred CD8⁺ T cells are sufficient for tumor elimination in the presence of host CD4⁺ T cells. (A–C) Mice bearing 5-week ID8 tumors were treated with wtNKG2D-expressing, chNKG2D-expressing, purified CD8⁺ chNKG2D-expressing or purified CD4⁺ chNKG2D-expressing T cells. (A) chNKG2D-expressing T cells gated on CD3e⁺ cells were assayed for NKG2D and CD8b expression by flow cytometry. (B) Eight weeks after tumor cell injection, the number of solid tumors on the peritoneal wall and number of tumor cells in the peritoneal wash was assessed. The average of each group and SD (n = 12) are shown. (C) WtNKG2D-expressing, chNKG2D-expressing, CD8⁺ chNKG2D-expressing and CD4⁺ chNKG2D-expressing T cells were cultured in standard conditions or together with RMA, RMA-Rae1 or ID8 tumor cells. Cell-free supernatants were assayed for interferon γ (IFNγ) production after 24 h. (*p < 0.01; ***p < 0.001 as compared with wtNKG2D-expressing T cells)