Figure 5.

CD8⁺ T cells from concomitantly immune mice recognize epitopes from DCT and gp100 melanocyte differentiation antigens. Mice received (A) inoculation of B16 cells in the right flank followed 6 d later by an identical inoculum in the left flank, (B) inoculation of B16 cells in the right flank combined with CD4 depletion on days 4 and 10, or (C) inoculation of B16 cells in the right flank followed 6 d later by an identical inoculum in the left flank and CD4 depletion on days 4 and 10. 12 d after primary tumor inoculation, CD8⁺ T cells from spleen and inguinal lymph nodes were tested by IFN-γ ELISPOT analysis using as targets either B16 cells or peptide-pulsed EL4 lymphoma cells. Lymph node and spleen cells were pooled from groups of 5–10 mice. Values represent the mean number of spots (n = 3–4 replicates/point) ± SD. Asterisks depict statistically significant differences (P < 0.05; by two-tailed Student's t test) between T cell responses to target EL4 cells pulsed with relevant versus irrelevant (Irr) peptide; or, for target B16 cells, differences between responses from naive versus tumor-bearing mice.