Effect of homeostatic T cell expansion on growth of a colon carcinoma cell line. Sublethally irradiated C57BL/6 mice were challenged subcutaneously with 105 MC-38 colon carcinoma cells, and half of the mice were transfused with 5 × 107 B6 LN cells. Tumor growth was inhibited in the transfused (triangles) compared with the nontransfused (squares) mice (both groups, n = 6).