ITGAM and neoplasm: At 24 h after I.V. injection of nAlb-Cy5, we found that ~ 8% of all live cells in the tumor were Cy5+ (Fig. S13) and, amongst Cy5+ cells, the majority were CD45−CD31− cells, which are primarily cancer cells, and tumor-associated CD11b+F4/80+ macrophages (Fig. 2k).