While CD206+ cells represented about 12.0 ± 2.4 % of the CD68+ cells in the non-irradiated group, it significantly increased to 50.7 ± 5.3% and 49.9 ± 6.1 % in the tumor mass early and late after radiation, respectively, without any change in the absolute number of M2 MΦ (Figure 2B). Here, MRC1 is linked to neoplasm.