MRC1 and neoplasm: In Frount-deficient mice, we observed reduced accumulation of both Ly-6Chi and Ly-6Clo monocytes/macrophages in tumor tissue, as well as a decrease in the proportion of CD206+ M2 macrophages, which are associated with tumor progression22 (Fig. 3b), but no decrease in the other immune cell populations in the tumor (Fig. 3c), as well as the hematopoietic cell populations under the steady-state condition in the bone marrow and peripheral blood (Supplementary Fig. 6).