Finally, we confirmed that the H22 nullbody was successfully internalized by U937, a monocytic human myeloid leukemia cell line expressing CD64 (Figure 2E and Supplementary Figure 2C) and by human blood monocytes (Figure 2F), and that the internalized ADCs were localized in lysosomes of blood monocytes (Figure 2F). The gene discussed is FCGR1A; the disease is myeloid leukemia.