T cells infiltrate SDF-B16F1 but not wild-type B16F1 tumors.

C57BL/6 mice were injected intradermally with wild-type B16F1 or SDF-B16F1 cells and tissues were collected for histology/immunohistochemistry, as described in “Materials and methods.” Tissue sections from samples collected at day 7 after tumor inoculation are shown here. Immune cell infiltrates (CD3, CD4, and CD8 T cells; arrows) are observed prominently in SDF-tumors, but not in wild-type tumors (original magnification × 10).