title: A novel cell surface molecule on early B-lineage cells.
abstract: B cells and their antibody-secreting progeny represent one of several differentiation pathways that haematopoietic stem cells (HSC) may enter. Cells representing intermediate stages between HSC and B cells have been identified in mammalian haematopoietic tissues and studied intensively over the past decade. This population of early B-lineage cells, termed pre-B, is characterized by cellular proliferation and an orderly cascade of immunoglobulin gene rearrangements, a combination of events leading to the generation of clonally diverse B cells which then migrate to peripheral lymphoid tissues. It remains to be determined what elements determine the polyclonal growth of pre-B cells, how immunoglobulin gene rearrangements are regulated, and what happens to pre-B cells undergoing 'non-productive' immunoglobulin gene rearrangements. These issues could be resolved more easily if early B-lineage cells could be identified precisely and isolated. Here, we describe a cell surface glycoprotein that is selectively expressed by pre-B and newly formed B cells in murine haematopoietic tissues. The molecule, a homodimer formed by disulphide-linked chains of relative molecular mass (Mr) 140,000, is identified by a mouse monoclonal alloantibody called BP-1.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface / Q000032:analysis*; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D001854:Bone Marrow Cells; D002454:Cell Differentiation; D002469:Cell Separation; D005434:Flow Cytometry; D007519:Isoantigens / Q000032:analysis*; D008099:Liver / Q000166:cytology; D051379:Mice; D008815:Mice, Inbred Strains; D009115:Muridae; D013154:Spleen / Q000166:cytology; D013950:Thymus Gland / Q000166:cytology
chemical_list: D000911:Antibodies, Monoclonal; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface; D007519:Isoantigens