title: Identification of immature and mature myeloma cells in the bone marrow of human myelomas.
abstract: With regard to the expression of adhesion molecules, human myeloma cells freshly isolated from bone marrow were heterogeneous. By two-color analysis with anti-VLA-5 antibody (PE staining) and FITC-labeled anti-CD38 antibody, we found all myeloma cells located at CD38-strong positive (CD38++) fraction and identified two subpopulations among these myeloma cells: CD38++ VLA-5-(VLA-5-) myeloma cells and CD38++ VLA-5+ (VLA-5+) myeloma cells. To clarify the biologic character of these two subpopulations, the morphology, in vitro proliferative activity and in vitro M-protein secretion were examined in each fraction isolated by the purification procedure or a cell sorter. Morphologic examination showed that VLA-5- myeloma cells were mostly immature or plasmablastic and VLA-5+ cells were mature myeloma cells. Furthermore, VLA-5- myeloma cells proliferated markedly in vitro and responded to interleukin 6 (IL-6), a growth factor for myeloma cells, while VLA-5+ myeloma cells showed very low uptakes of 3H-thymidine and no responses to IL-6 but secreted higher amounts of M-protein (immunoglobulin) in vitro significantly. Therefore, we could clarify here heterogeneity of human myeloma cells in the bone marrow with regard to the expression of VLA-5, one of integrin adhesion molecules; VLA-5- myeloma cells were proliferative immature cells and VLA-5+ cells were mature myeloma cells.
authors.affiliation: Department of Internal Medicine, Research Institute for Nuclear Medicine and Biology, Hiroshima University, Japan.
authors.forename: M M
authors.initials: MM
authors.lastname: Kawano
authors.forename: N
authors.initials: N
authors.lastname: Huang
authors.forename: H
authors.initials: H
authors.lastname: Harada
authors.forename: Y
authors.initials: Y
authors.lastname: Harada
authors.forename: A
authors.initials: A
authors.lastname: Sakai
authors.forename: H
authors.initials: H
authors.lastname: Tanaka
authors.forename: K
authors.initials: K
authors.lastname: Iwato
authors.forename: A
authors.initials: A
authors.lastname: Kuramoto
mesh_terms: D036541:ADP-ribosyl Cyclase; D051997:ADP-ribosyl Cyclase 1; D015703:Antigens, CD / Q000032:analysis; D000943:Antigens, Differentiation / Q000032:analysis; D001483:Base Sequence; D001853:Bone Marrow / Q000473:pathology*; D002455:Cell Division; D002999:Clone Cells / Q000473:pathology; D004273:DNA, Neoplasm / Q000032:analysis; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D016130:Immunophenotyping; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D009101:Multiple Myeloma / Q000235:genetics / Q000276:immunology / Q000473:pathology*; D010950:Plasma Cells / Q000276:immunology / Q000473:pathology; D016133:Polymerase Chain Reaction; D017469:Receptors, Fibronectin / Q000032:analysis; D016029:Receptors, Very Late Antigen / Q000032:analysis
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D004273:DNA, Neoplasm; D007074:Immunoglobulin G; D008562:Membrane Glycoproteins; D017469:Receptors, Fibronectin; D016029:Receptors, Very Late Antigen; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D051997:ADP-ribosyl Cyclase 1