3-Monochloropropane-1,2-diol (3-MCPD) fatty acid esters are process contaminants mainly formed during the refinement of vegetable oils. Gastrointestinal hydrolysis yields free 3-MCPD, which is resorbed into the body. In long-term rat studies, 3-MCPD caused renal and testicular neoplasms.
View Article and Find Full Text PDFBackground And Aims: Previous trials on acupuncture in alcohol addiction were in outpatients and focused on relapse prevention. Rates of dropout were high and interpretation of results difficult. We compared auricular laser and needle acupuncture with sham laser stimulation in reducing the duration of alcohol withdrawal.
View Article and Find Full Text PDFThe effects of recombinant thrombopoietin (TPO) alone and in combination with erythropoietin (EPO) and early-acting cytokines such as interleukin 3 (IL-3), stem cell factor (SCF) and GM-CSF on highly purified mobilized human CD34+ progenitor cells were studied in a serum-depleted culture system. Eight leukapheresis samples were cultured for seven days and analyzed; aliquots were replated and re-evaluated on day 12. Three-color flow cytometry was used together with morphologic analysis to determine proliferation and megakaryocytic or erythroid maturation.
View Article and Find Full Text PDFWe report our observations with the cell line LW/SO, which was recently derived from the bone marrow of a patient with acute myeloid leukemia. Based on the morphological and histochemical examination, the leukemic cells were classified primarily as FAB type M4. However, 2 years later, in relapse, the cells changed their morphology and were hence specified as FAB type M2 (slightly positive for acid phosphatase and Sudan black).
View Article and Find Full Text PDFObjective: To study the regulation of granulocyte macrophage colony stimulating factor (GM-CSF) production by human articular chondrocytes which may contribute to the local GM-CSF production encountered in rheumatoid joints. This growth factor induces human macrophages to migrate and proliferate, improves their accessory function and increases the expression of HLA-DR antigens on macrophages and macrophage-like synoviocytes.
Methods: GM-CSF was assayed by ELISA and a bioassay in cell and organ culture supernatants from human articular chondrocytes, by in situ hybridization, Northern blot analysis and affinity chromatography.
The GM/SO cell line bears a high level of stem cell factor receptors (SCF-R) i.e. c-kit protein, and therefore constitutes a potential model for studying the regulation of this crucial receptor on myeloid cells.
View Article and Find Full Text PDFBy employing a monoclonal antibody against the stem cell factor receptor (SCF-R), c-kit oncogene product, we analysed in flow cytometric technique the density of SCF-R on GM/SO cells which were incubated under various culture conditions. These experiments revealed that there is an inverse correlation between the SCF-R density on the cells and the doses of granulocyte-macrophage colony-stimulating factor (GM-CSF) in culture medium; the lower the dose, the higher the density of SCF-R on the cells. More detailed analyses showed that, in contrast to SCF which rapidly downregulates its own receptor, GM-CSF does not alter the measurable level of SCF-R in an exposition period of 60 minutes, which suggests that the internalization or shedding of the receptor is not the mechanism of action.
View Article and Find Full Text PDFTo evaluate the effect of colony-stimulating factors and interferon gamma on the oxidative burst capacity of neutrophils in chronic granulomatous disease (CGD) we studied the neutrophils of a patient with variant CGD both from peripheral blood and from bone marrow culture on day 7 and 14. The results revealed that preincubation of peripheral neutrophils for 24 h in medium containing recombinant human granulocyte colony-stimulating factor (rhG-CSF), recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF), and recombinant human interferon gamma (rhIFN-gamma) alone or in combination did not improve the maximal oxidative burst activity measured by MTT assay. The colonies of this patient formed in agar assay were either composed of predominantly nitroblue tetrazolium (NBT)-positive cells or completely unable to reduce NBT.
View Article and Find Full Text PDFBased on the granulocyte-macrophage colony-stimulating factor (GM-CSF) dependency of a newly established human myeloid cell line GM/SO, we developed a highly specific and sensitive bioassay for human GM-CSF. The presence of bioactive GM-CSF could be determined by measuring the formazan concentration produced from MTT by the cells that survived and proliferated in the presence of either natural or recombinant human GM-CSF. With this assay we were able to quantify the level of GM-CSF in two human sera as well as in conditioned media from human bladder cell carcinoma cell line 5637, a human fibroblast line, and phytohemagglutinin-stimulated peripheral blood mononuclear cells.
View Article and Find Full Text PDFA new human myeloid cell line has been established recently from the bone marrow cells of a patient with chronic myelogenous leukemia in blast crisis. The active proliferation and survival of the cells in RPMI 1640 medium containing fetal calf serum are clearly dependent on the presence of either natural or recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF). Despite permanent culturing in rhGM-CSF (100 U/mL), the cells do not differentiate and bear the myelomonocytic surface markers CD34, CD13, CD36, as well as HLA-DR, but not CD3, CD7, CD10, CD11b, CD14, CD20, or CD42b.
View Article and Find Full Text PDFBy making use of the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) reducing ability of stimulated human neutrophils, we developed an alternative method to quantify the adherence of neutrophils in vitro. After discarding non-adherent neutrophils, the adherent cells were exposed to MTT solution containing 10 ng/ml phorbol 12-myristate 13-acetone (PMA). Subsequently, MTT reduced by this simultaneous stimulation was measured optically and used to calculate percent of adhesion.
View Article and Find Full Text PDFThe colorimetric assay previously described by Mosmann for the measurement of cell viability and proliferation has been modified for the assessment of the functional state of human polymorphnuclear cells (PMNs). The ability of PMNs to reduce the tetrazolium salt MTT to formazan reflects directly the degree of stimulation induced by various agents. The underlying mechanism of MTT-reduction to formazan seems to be similar to that of nitroblue tetrazolium (NBT)-reduction.
View Article and Find Full Text PDFNatural killer cell cytotoxic factor (NKCF), a cytotoxic factor contributing to human natural killer cell-mediated cytotoxicity, was generated from lymphocyte-conditioned medium using various stimuli. Crude NKCF activity was concentrated, and partially purified by ammonium sulfate precipitation and gel filtration. NKCF activities eluted as two molecular weight peaks, corresponding to Mr 33,000-43,000 (pool I) and approximately Mr 5,000 (pool II).
View Article and Find Full Text PDFHuman pluripotent colony stimulating factor (Pluripoietin) was shown to act synergistically with human pluripotent alpha-like colony-stimulating activity (Pluripoietin-alpha) supporting the proliferation and differentiation of human CFU-GM progenitor cells in vitro, increasing colony size and numbers. In addition, Pluripoietin enhanced cytotoxic activity of mature human neutrophil granulocytes in an antibody-dependent cellular cytotoxicity assay. Biological activities of Pluripoietin known so far suggest great potentials for clinical use.
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