title: Immature B cells in bone marrow express Fas/FasL.
abstract: Negative selection is a process by which autoreactive lymphocytes are eliminated from the developing antigen receptor repertoire. The mechanisms regulating negative selection of immature B lymphocytes in the bone marrow are poorly elucidated. Human bone marrow cells were examined in order to investigate the presence of the members of the Fas (APO-1/CD95) system. Here we demonstrate the expression of Fas in immature B lymphocytes (CD10/CD19+/CD40+/sIg+), and the presence of Fas natural ligand (FasL) in CD19+ bone marrow cells. The observed expression of apoptosis-related molecules might indicate how negative selection of autoreactive B cells can occur in human bone marrow.
authors.affiliation: Department of Immunotechnology, Lund University, Lund, Sweden.
authors.forename: N
authors.initials: N
authors.lastname: Nilsson
authors.forename: S
authors.initials: S
authors.lastname: Ingvarsson
authors.forename: C A
authors.initials: CA
authors.lastname: Borrebaeck
mesh_terms: D018941:Antigens, CD19 / Q000096:biosynthesis; D017209:Apoptosis / Q000276:immunology; D016175:B-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D001854:Bone Marrow Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D002454:Cell Differentiation / Q000276:immunology; D002461:Cell Line, Transformed; D053222:Fas Ligand Protein; D006801:Humans; D008024:Ligands; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000276:immunology / Q000378:metabolism; D011947:Receptors, Antigen, B-Cell / Q000096:biosynthesis; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000276:immunology; D019014:fas Receptor / Q000096:biosynthesis* / Q000378:metabolism
chemical_list: D018941:Antigens, CD19; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008024:Ligands; D008562:Membrane Glycoproteins; D011947:Receptors, Antigen, B-Cell; D019014:fas Receptor