CCR8 and colorectal neoplasm: CT26 and MC38 murine colorectal tumors were initiated in female Balb/c and C57Bl6 mice, respectively, and when the tumors reached a volume of ~200 mm3, the mice were randomized into the groups of four animals, and injected into the tail vein with either 200 μCi anti-CCR8 111In-IgG or 111In-Fab.