A monoclonal antibody to exfoliated surface vesicles that recognizes a membrane-associated erythroid burst-promoting activity.
A monoclonal antibody (MoAb) recognizing a membrane-associated erythroid burst-promoting factor was prepared by immunizing BALB/c mice with plasma membrane-derived vesicles exfoliated from lymphocytes under serum-free conditions. Hybrids secreting antibody reactive with lymphocyte plasma membranes were formally cloned and IgG was purified from monoclonal supernatants or from BALB/c mouse ascites fluid. Two clones (D3-E4 and D3-G9) were found to suppress burst forming unit-erythroid (BFU-E) proliferation when added directly to serum-free human marrow culture. Inhibition to a level of 100% was observed in a dose-dependent fashion over a wide range of antibody concentrations (0-200 micrograms/mL). Neither antibody altered the proliferation of colony forming unit-granulocyte macrophage (CFU-GM) or colony forming unit-granulocyte-erythroid-monocyte-megakaryocyte (CFU-GEMM) progenitor cells in human bone marrow culture. The D3-E4 clone was found to produce an IgG1 antibody which adsorbs an erythroid burst-promoting activity (BPA) from supernatants of, and octylglucoside extracts of shed vesicles present in, serum-free, lymphocyte conditioned medium (LCM), and which recognizes a vesicular protein of Mr approximate 30,000 on immunoblots of membrane proteins electrophoresed on sodium dodecyl sulfate (SDS)/polyacrylamide and transferred to nitrocellulose. In contrast, the D3-G9 clone was found to produce an IgG1 cytotoxic antibody. These antibodies will be important to the study of cell-cell and growth factor-cell interactions in vitro.
Department of Medicine, St Elizabeth's Hospital, Boston, MA 02135.
N
N
Dainiak
G
G
Warren
D
D
Sutter
S
S
Kreczko
D
D
Howard
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000502:physiology; D000954:Antigens, Surface / Q000276:immunology* / Q000302:isolation & purification; D001854:Bone Marrow Cells; D003114:Colony-Forming Units Assay; D004920:Erythropoiesis; D005260:Female; D006131:Growth Inhibitors / Q000502:physiology; D006412:Hematopoietic Stem Cells / Q000276:immunology; D006801:Humans; D007166:Immunosuppressive Agents; D008222:Lymphokines / Q000276:immunology* / Q000302:isolation & purification; D008562:Membrane Glycoproteins / Q000276:immunology* / Q000302:isolation & purification; D051379:Mice; D008807:Mice, Inbred BALB C; D019714:Tissue Inhibitor of Metalloproteinases
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D006131:Growth Inhibitors; D007166:Immunosuppressive Agents; D008222:Lymphokines; D008562:Membrane Glycoproteins; D019714:Tissue Inhibitor of Metalloproteinases