Isolation and characterization of a monoclonal antibody that recognizes the human c-kit receptor.
Stem cell factor (SCF) stimulates the growth of burst-forming unit-erythroid (BFU-E) and colony-forming unit granulocyte-macrophage (CFU-GM) by binding to a specific cell surface receptor. The receptor for SCF is encoded by the protooncogene c-kit. After immunizing mice with the human erythroleukemia cell line OCIM1, we obtained a monoclonal antibody (MoAb) that recognizes the human c-kit receptor. This MoAb, designated SR-1, blocks binding of 125I-human SCF to the c-kit receptor, and neutralizes the biologic effects of SCF in hematopoietic colony assays. With few exceptions, c-kit expression was identified on all hematopoietic and lymphoid cell lines tested by indirect immunofluorescent analysis using SR-1 and by binding studies with 125I-SCF. SR-1 recognizes a small fraction of normal bone marrow mononuclear cells, and these cells have the morphologic appearance of blasts. Colony assays show that BFU-E and CFU-GM display the c-kit receptor. SR-1 does not cross-react with murine c-kit protein, indicating that the binding epitopes of the human and murine c-kit receptors are antigenically distinct. This MoAb may be useful to characterize the spectrum of cells that display the c-kit receptor and to further define the role of SCF in hematopoiesis.
Department of Medicine, University of Washington, Seattle 98195.
V C
VC
Broudy
N
N
Lin
K M
KM
Zsebo
N C
NC
Birkett
K A
KA
Smith
I D
ID
Bernstein
T
T
Papayannopoulou
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000302:isolation & purification*; D000918:Antibody Specificity; D000951:Antigens, Neoplasm / Q000276:immunology; D001854:Bone Marrow Cells; D015672:Erythroid Precursor Cells / Q000737:chemistry; D005260:Female; D005455:Fluorescent Antibody Technique; D006098:Granulocytes / Q000737:chemistry; D016298:Hematopoietic Cell Growth Factors / Q000037:antagonists & inhibitors / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000737:chemistry; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute / Q000276:immunology; D008214:Lymphocytes / Q000737:chemistry; D008264:Macrophages / Q000737:chemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D011518:Proto-Oncogene Proteins / Q000032:analysis / Q000276:immunology* / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit; D019089:Stem Cell Factor; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D016298:Hematopoietic Cell Growth Factors; D011518:Proto-Oncogene Proteins; D019089:Stem Cell Factor; D019009:Proto-Oncogene Proteins c-kit