MKI67 and neoplasm: The frequency of CD8+ T cells expressing tumor-reactive T cell markers, PD-1, and Ki-67, was comparable between Ccl21a-KO and WT mice; however, the frequency of H-2Kb TRP-2 tetramer-specific IFN-γ+ CD8+ T cells was elevated in Ccl21a-KO tumors, suggesting that anti-melanoma immunity was enhanced in the KO mice (Fig. 3B).