To further elucidate the role of CXCR4 in macrophage migration and intestinal invasion in vivo, we purified CXCR4+CD11b+ and CXCR4-CD11b+ cells from mouse bone marrow and transferred them intravenously into an orthotopic CRC mouse model 8 days after Luc-GFP-CT26 injection (Figure S6A). Here, ITGAM is linked to colorectal carcinoma.