Reduced tumor growth in mice injected with α-MSH treated CD8⁺ T cells.

<p>(<b>A</b>) Wt mice were inoculated with 1×10⁵ B16-OVA cells and injected with 5×10⁶ PBS or α-MSH stimulated CD8⁺ T cells from OT-1 mice at d8 and d10 after inoculation of tumor cells. Tumor growth was monitored over time in n = 18 mice in three independent experiments. * <i>P</i><0.05 vs. transfer of PBS stimulated CD8⁺ T cells. (<b>B</b>) Immunofluorescence staining of tumor tissue at d22 after inoculation of tumor cells using antibodies directed against CD8 and granzyme B. Original magnification: 400×, scale bar = 25 µm. Cells expressing CD8 and granzyme B are marked by arrows. (<b>C</b>) MC-1R signaling is important for MHC class I-restricted anti-tumoral immunity. Wt and C57BL/6J^e/e mice were inoculated with indicated concentrations of B16 cells and tumor growth was monitored over time. One representative out of three independent experiments is shown. * <i>P</i><0.05 vs. wt. (<b>D</b>) Immunofluorescence staining of contralateral and tumor-draining lymph nodes from wt mice (i and ii) as well as C57BL/6J^e/e mice (iii and iv) at d20 after inoculation of 25,000 B16 cells using antibodies directed against CD8 and granzyme B. Original magnification: 300×, scale bar = 25 µm. Cells expressing CD8 and granzyme B are marked by arrows.