Identification and purification of the human myeloid differentiation antigen recognized by monoclonal antibody AHN-7.
This report describes the characterization and expression of a human myeloid differentiation antigen defined by use of an IgG1 monoclonal antibody (AHN-7). This antibody binds to many granulocytic precursors in normal marrow, to most but not all granulocyte-macrophage progenitors (CFU-GM), and to approximately half of nonlymphoid leukemia specimens. The protein antigens recognized by AHN-7 were purified from 35S-labelled HL-60 cells by antibody affinity column chromatography. The molecule reacting with AHN-7 was markedly heterogeneous, appearing as several forms ranging in pl from 4.5 to 6.4 with apparent molecular weights from 43,000 to 68,000. The molecules were not disulfide-linked. Proteins bearing the antigen were minor components of the plasma membrane. The antigen was expressed by normal human peripheral blood neutrophils, monocytes, eosinophils, and basophils, and weakly on a small percentage of lymphocytes; it was not detected in red blood cells, platelets, or the majority of lymphocytes. The antibody also bound to a variety of human myeloid leukemia cell lines but not to any lymphoid leukemia cell line tested. AHN-7 had no effect on several in vitro neutrophil functions tested.
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface / Q000276:immunology / Q000302:isolation & purification*; D002454:Cell Differentiation; D002460:Cell Line; D003602:Cytotoxicity, Immunologic; D000939:Epitopes; D006098:Granulocytes / Q000276:immunology*; D006801:Humans; D007951:Leukemia, Myeloid / Q000276:immunology; D015470:Leukemia, Myeloid, Acute / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology*; D008565:Membrane Proteins / Q000276:immunology / Q000302:isolation & purification; D008970:Molecular Weight; D009000:Monocytes / Q000276:immunology*; D009504:Neutrophils / Q000502:physiology; D010587:Phagocytosis
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D000939:Epitopes; D008565:Membrane Proteins