CD33 and neoplasm: Bone marrow cells constitute a key cellular component of immune cells that infiltrate tumors and play an important role in the regulation of tumor inflammation and angiogenesis.[31] Eruslanov et al indicated that peripheral blood from BC patients contains 2 major CD11b myeloid cell subsets: granulocyte-type CD15-high CD33-low cells and monocyte-type CD15-low CD33-high cells.