title: Analysis of T-cell-derived factors with the use of B-prolymphocytic leukemia cells.
abstract: Mononuclear cells of five patients with B-prolymphocytic leukemia were tested for their functional capacities in vitro after stimulation. Leukemic B cells from these patients have a mature phenotypic marker profile and can be obtained in high numbers from peripheral blood. B cells of all five patients proliferated in response to phorbol myristate acetate. In one patient, this proliferation was strongly enhanced by the addition of T-cell-conditioned medium. Conditioned medium by itself or interleukin 2 in the presence or absence of the phorbol ester was not active. This enabled us to develop an assay for a B-cell growth factor different from interleukin 2. Next to their proliferative capacities, we found that malignant B cells of three of the five patients secreted large amounts of IgM when stimulated with pokeweed mitogen or interleukin 2 in the presence of allogeneic T cells. In the absence of these allogeneic cells, neither pokeweed mitogen nor interleukin 2 had any effect. However, T-cell-conditioned medium as well as the supernatants of two T-cell hybridomas induced strong IgM production in the absence of T cells. Thus, neoplastic B cells of some patients with B-prolymphocytic leukemia can be stimulated to proliferation and differentiation in vitro and can be used as an assay and model system to study the effect of T cells and/or T-cell factors in human B-cell activation.
authors.affiliation: Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam.
authors.forename: R W
authors.initials: RW
authors.lastname: Sauerwein
authors.forename: W G
authors.initials: WG
authors.lastname: van der Meer
authors.forename: T
authors.initials: T
authors.lastname: Logtenberg
authors.forename: L A
authors.initials: LA
authors.lastname: Aarden
mesh_terms: D000368:Aged; D000912:Antibodies, Neoplasm / Q000378:metabolism; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis; D000951:Antigens, Neoplasm / Q000032:analysis; D001402:B-Lymphocytes / Q000187:drug effects*; D002454:Cell Differentiation / Q000187:drug effects; D003470:Culture Media / Q000032:analysis; D006801:Humans; D007075:Immunoglobulin M / Q000378:metabolism; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4; D007378:Interleukins / Q000302:isolation & purification / Q000494:pharmacology*; D007945:Leukemia, Lymphoid / Q000473:pathology*; D007963:Leukocytes, Mononuclear / Q000187:drug effects*; D008213:Lymphocyte Activation / Q000187:drug effects; D010641:Phenotype; D013601:T-Lymphocytes / Q000032:analysis*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D000912:Antibodies, Neoplasm; D000944:Antigens, Differentiation, B-Lymphocyte; D000951:Antigens, Neoplasm; D003470:Culture Media; D007075:Immunoglobulin M; D007376:Interleukin-2; D007378:Interleukins; D015847:Interleukin-4; D013755:Tetradecanoylphorbol Acetate