Figure 2.

Generation of gp100-expressing MC38 tumor cell lines. (A) Schematic representation of viral vector containing human full-length gp100, an internal ribosomal entry site, and the mIL-4R gene. The construct was transduced into MC38 cells, which were then sorted based on IL-4R expression, as shown in right subpanel. (B) IFN-γ secretion by pmel-1 T cells in response to MC38/gp100 tumors. Pmel-1 T cells were cocultured with the indicated murine tumor cell lines. Twenty-four hours later, IFN-γ concentrations in the supernatants were detected by ELISA. B16 melanoma cells pretreated with IFN-γ were used as a positive control. (C) Growth of MC38/gp100 tumors in C57BL/6 albino mice. C57BL/6 albino mice were s.c. injected with 5 × 10⁵ MC38 or MC38/gp100. Tumor sizes were measured every 3 d. (D) Treatment of MC38/gp100 tumors with pmel-1 T cells. C57BL/6 albino mice were s.c. injected with 5 × 10⁵ MC38 or MC38/gp100. Six days later, all mice were received 350cGy irradiation. Seven days later, 5×10⁶ (5M) pmel-1 T cells were transferred into tumor-bearing mice, along with 5 × 10⁵ gp100 peptide-pulsed DC, both by intravenous injection, and systemic IL-2 treatment. Tumor-bearing mice receiving irradiation only served as the control group. Tumor sizes were measured every 3 d. Pmel-1 T cells suppressed the growth of MC38/gp100 tumors, but not MC38 tumors. Data are plotted as the mean of five mice per group + SEM. Results are representative of two experiments. (E) Pmel-1 T cells migrate specifically to MC38/gp100 tumors. C57BL/6 albino mice were subcutaneously injected with 5×10⁵ MC38/gp100 in the right flank. The same number of MC38 tumor cells was implanted on the left flank. Seven days after tumor implantation, 1×10⁶ sorted luciferase expressing pmel-1 T cells were transferred to tumor-bearing mice. Six days after adoptive transfer, the intensity of luciferase signaling was measured. Data shown were representative of five mice.