title: Development of a bone marrow culture for maintenance and growth of normal human B cell precursors.
abstract: The absence of long term bone marrow cultures for studying the growth and differentiation of human B cell precursors (BCP) has placed restrictions on the ability to analyze the early stages of human B cell ontogeny. We now describe a bone marrow-derived adherent cell microenvironment that maintains human BCP for several weeks in vitro. The adherent cells are maintained in a serum-free tissue culture medium, and consist of a predominant population of CD10+ fibroblast-like cells and a minor population of CD10+/nonspecific esterase+ macrophages. Adherent cell cultures seeded with fresh or cryopreserved fetal bone marrow, or purified CD10+/surface IgM- cells, provide a supportive microenvironment for lymphoid cells with a predominant phenotype of CD10+/CD19+/HLA-DR+/surface IgM-. Supplementation of the adherent cell cultures with human IL-7 induces active growth of BCP during the first 14 to 21 days of culture. However, the expansion of these cells does not continue past 21 days, and the cultures undergo a steady decline in BCP. Analysis of adherent cell conditioned medium revealed the presence of an unidentified soluble factor (or factors) that acts in concert with IL-7 to promote the growth of CD10+/surface IgM- cells. This culture system will be useful in elucidating the patterns of gene expression and growth factor requirements that characterize normal human B cell ontogeny, and perturbations of normal B cell ontogeny that lead to immunodeficiency and leukemia.
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis 55455.
authors.forename: M L
authors.initials: ML
authors.lastname: Wolf
authors.forename: J A
authors.initials: JA
authors.lastname: Buckley
authors.forename: A
authors.initials: A
authors.lastname: Goldfarb
authors.forename: C L
authors.initials: CL
authors.lastname: Law
authors.forename: T W
authors.initials: TW
authors.lastname: LeBien
mesh_terms: D015703:Antigens, CD / Q000032:analysis*; D018952:Antigens, CD34; D019011:Antigens, CD7; D000943:Antigens, Differentiation / Q000032:analysis; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D000951:Antigens, Neoplasm / Q000032:analysis; D001402:B-Lymphocytes / Q000166:cytology*; D001854:Bone Marrow Cells; D019013:CD40 Antigens; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D005434:Flow Cytometry; D006801:Humans; D066298:In Vitro Techniques; D015851:Interleukin-7 / Q000494:pharmacology; D015260:Neprilysin; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D063268:Sialic Acid Binding Ig-like Lectin 3
chemical_list: D015703:Antigens, CD; D018952:Antigens, CD34; D019011:Antigens, CD7; D000943:Antigens, Differentiation; D000944:Antigens, Differentiation, B-Lymphocyte; D015214:Antigens, Differentiation, Myelomonocytic; D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; C571163:CD33 protein, human; D019013:CD40 Antigens; D015851:Interleukin-7; D011947:Receptors, Antigen, B-Cell; D063268:Sialic Acid Binding Ig-like Lectin 3; D015260:Neprilysin