title: PB76: a novel surface glycoprotein preferentially expressed on mouse pre-B cells and plasma cells detected by the monoclonal antibody G-5-2.
abstract: A monoclonal antibody (mAb) G-5-2 was isolated which binds to transformed as well as normal cells of the B lineage but not to cells of the T cell, myeloid lineages nor to fibroblasts. mAb G-5-2 reacts with pre-B and plasma cell-transformed lines, and it preferentially recognizes normal pre-B cells from fetal liver and bone marrow as well as plasma cells from spleen of mice. G-5-2+ fetal liver cells isolated by cell sorter express mRNA for mu heavy chain Ig gene and generate in vitro antibody-producing cells when co-cultured with lipopolysaccharide and rat thymocyte filler cells. During development the frequency and staining intensity of G-5-2+ cells in fetal liver from normal mice increases from 1% G-5-2+ cells at day 14 to approximately 7% positive cells at day 18 of gestation. Several strains or normal mice contain comparable numbers of G-5-2+ cells as well as B-220+ and BP-1+ B cell precursors in the fetal liver. Mice carrying the xid mutation have 3-4-fold less G-5-2+ as well as B-220+ and BP-1+ cells in the fetal liver, suggesting that the effects of the xid mutation may be manifested from early stages of B cell development. Fetal liver cells from mice carrying the scid mutation were found to contain normal numbers of G-5-2+ as well as B-220+ and BP-1+ pre-B cells. These results indicate that differentiation from progenitors to pre-B cells in scid mice may occur normally; the scid mutation would thus appear to affect the process of rearrangement and expression of the Ig genes in the developing pre-B cells. mAb G-5-2 precipitates a 76-kDa glycoprotein from surface-radiolabeled pre-B cells and plasma cells. Taken together, these results indicate that G-5-2 mAb recognizes a novel B cell lineage-specific surface molecule called PB76 which is preferentially expressed by pre-B cells and plasma cells.
authors.affiliation: Basel Institute for Immunology, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Strasser
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology*; D001402:B-Lymphocytes / Q000145:classification / Q000166:cytology / Q000276:immunology*; D002454:Cell Differentiation; D002460:Cell Line; D002469:Cell Separation; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins / Q000276:immunology*; D008099:Liver / Q000166:cytology; D051379:Mice; D008970:Molecular Weight; D010950:Plasma Cells / Q000276:immunology*; D013154:Spleen / Q000166:cytology
chemical_list: D000911:Antibodies, Monoclonal; D000944:Antigens, Differentiation, B-Lymphocyte; D006023:Glycoproteins