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Cytometry. Part a : the Journal of the... Jul 2012Multiple wavelength operation in a flow cytometer is an exciting way for cell analysis based on both fluorescence and optical scattering processing. For example, this...
Multiple wavelength operation in a flow cytometer is an exciting way for cell analysis based on both fluorescence and optical scattering processing. For example, this multiparametric technique is currently used to differentiate blood cells subpopulations. The choice of excitation wavelengths matching fluorochrome spectra (it is currently the opposite) and the use of a broader range of fluorochromes can be made by taking advantage of a filtered supercontinuum white light source. In this study, we first wished to validate the use of a specific triggered supercontinuum laser in a flow cytometer based on white light scattering and electric sizing on human blood cells. Subsequently, to show the various advantages of this attractive system, using scattering effect, electrical detections, and fluorescence analysis, we realized cells sorting based on DNA/RNA stained by thiazole orange. Discrimination of white blood cells is efficiently demonstrated by using a triggered supercontinuum-based flow cytometer operating in a "one cell-one shot" configuration. The discriminated leukocyte populations are monocytes, lymphocytes, granulocytes, immature granulocytes, and cells having a high RNA content (monoblasts, lymphoblasts, and plasma cells). To the best of our knowledge, these results constitute the first practical demonstration of flow cytometry based on triggered supercontinuum illumination. This study is the starting point of a series of new experiments fully exploiting the spectral features of such a laser source. For example, the large flexibility in the choice of the excitation wavelength allows to use a larger number of fluorochromes and to excite them more efficiently. Moreover, this work opens up new research directions in the biophotonics field, such as the combination of coherent Raman spectroscopy and flow cytometry techniques.
Topics: Benzothiazoles; DNA; Flow Cytometry; Fluorescent Dyes; Humans; Lasers; Leukocyte Count; Leukocytes, Mononuclear; Light; Nucleic Acids; Quinolines; RNA; Scattering, Radiation
PubMed: 22573492
DOI: 10.1002/cyto.a.22065 -
Pulsating electromagnetic field stimulation prevents cell death of puromycin treated U937 cell line.Journal of Physiology and Pharmacology... Apr 2010Aim of study was to verify whether pulsating electromagnetic field (PEMF) can affect cancer cells proliferation and death. U937 human lymphoid cell line at densities...
Aim of study was to verify whether pulsating electromagnetic field (PEMF) can affect cancer cells proliferation and death. U937 human lymphoid cell line at densities starting from 1 x 10(6) cells/ml to 0.0625 x 10(6) cells/ml, were exposed to a pulsating magnetic field 50 Hz, 45+/-5 mT three times for 3 h per each stimulation with 24 h intervals. Proliferation has been studied by counting number of cells stimulated and non-stimulated by PEMF during four days of cultivation. Viability of cells was analyzed by APC labeled Annexin V and 7-AAD (7-amino-actinomycin D) dye binding and flow cytometry. Growing densities of cells increase cell death in cultures of U937 cells. PEMF exposition decreased amount of cells only in higher densities. Measurement of Annexin V binding and 7-AAD dye incorporation has shown that density-induced cell death corresponds with decrease of proliferation activity. PEMF potentiated density-induced death both apoptosis and necrosis. The strongest influence of PEMF has been found for 1 x 10(6)cells/ml and 0.5 x 10(6) cells/ml density. To eliminate density effect on cell death, for further studies density 0.25 x 10(6) cells/ml was chosen. Puromycin, a telomerase inhibitor, was used as a cell death inducer at concentration 100 microg/ml. Combined interaction of three doses of puromycin and three fold PEMF interaction resulted in a reduced of apoptosis by 24,7% and necrosis by 13%. PEMF protects U937 cells against puromycin- induced cell death. PEMF effects on the human lymphoid cell line depends upon cell density. Increased density induced cells death and on the other hand prevented cells death induced by puromycin.
Topics: Antimetabolites, Antineoplastic; Apoptosis; Cell Proliferation; Cell Survival; Electromagnetic Fields; Humans; Lymphoma, Large B-Cell, Diffuse; Necrosis; Puromycin; U937 Cells
PubMed: 20436221
DOI: No ID Found -
Poultry Science Dec 2009This study was conducted to determine effects of methyltestosterone on innate immunity and adaptive immunity against Salmonella Pullorum in dwarf chicks. In vivo... (Randomized Controlled Trial)
Randomized Controlled Trial
This study was conducted to determine effects of methyltestosterone on innate immunity and adaptive immunity against Salmonella Pullorum in dwarf chicks. In vivo experiment, comparisons of pathological sections, viable counts of bacteria, specific antibody levels, and subsets of T lymphocytes were set forth between chicks with or without 10(-7) M methyltestosterone treatment (2 d of age through 21 d of age) and challenged with 5 x 10(8) virulent Salmonella Pullorum (7 d of age), and in vitro experiment, phagocytic and killing abilities, reactive oxygen intermediate production, and reactive nitrogen intermediate production of monocytes-macrophages treated with high (10(-8) M/10(6) cell) or physiological (10(-14) M/10(6) cell) concentration of methyltestosterone were examined after Salmonella Pullorum infection. The results showed that (1) in vivo, administration of methyltestosterone enhanced susceptibility to Salmonella Pullorum infection and depressed cellular immunity against Salmonella Pullorum, whereas it had no effect on humoral immunity in dwarf chicks; (2) in vitro, at high concentration, methyltestosterone reduced (P < 0.05) monocytes-macrophages mediated reactive oxygen intermediate-dependent killing of Salmonella Pullorum, whereas low concentration of methyltestosterone enhanced (P < 0.05) reactive oxygen intermediate-dependent killing of Salmonella Pullorum in male dwarf chicks but not in females; and (3) although challenged with Salmonella Pullorum, phagocytic ability and monocytes-macrophages mediated reactive nitrogen intermediate-dependent killing were not affected by methyltestosterone in vitro. The results indicated that methyltestosterone affected the immune response to Salmonella Pullorum in dwarf chicks by changing monocytes-macrophages mediated reactive oxygen intermediate-dependent killing and cellular immunity, and the effects were dose-dependent; furthermore, the former 2 pathways played important roles in preventing Salmonella Pullorum infection in dwarf chicks, although the mechanism needs further study.
Topics: Administration, Oral; Anabolic Agents; Animals; Chickens; Female; Male; Methyltestosterone; Monocyte-Macrophage Precursor Cells; Nitrogen; Poultry Diseases; Reactive Oxygen Species; Salmonella; Salmonella Infections, Animal
PubMed: 19903952
DOI: 10.3382/ps.2009-00298 -
Clinical Cancer Research : An Official... Apr 2014Recent studies suggested that AKT activation might confer poor prognosis in acute myelogenous leukemia (AML), providing the rationale for therapeutic targeting of this...
PURPOSE
Recent studies suggested that AKT activation might confer poor prognosis in acute myelogenous leukemia (AML), providing the rationale for therapeutic targeting of this signaling pathway. We, therefore, explored the preclinical and clinical anti-AML activity of an oral AKT inhibitor, MK-2206. Experimental Methods: We first studied the effects of MK-2206 in human AML cell lines and primary AML specimens in vitro. Subsequently, we conducted a phase II trial of MK-2206 (200 mg weekly) in adults requiring second salvage therapy for relapsed/refractory AML, and assessed target inhibition via reverse phase protein array (RPPA).
RESULTS
In preclinical studies, MK-2206 dose-dependently inhibited growth and induced apoptosis in AML cell lines and primary AML blasts. We then treated 19 patients with MK-2206 but, among 18 evaluable participants, observed only 1 (95% confidence interval, 0%-17%) response (complete remission with incomplete platelet count recovery), leading to early study termination. The most common grade 3/4 drug-related toxicity was a pruritic rash in 6 of 18 patients. Nevertheless, despite the use of MK-2206 at maximum tolerated doses, RPPA analyses indicated only modest decreases in Ser473 AKT (median 28%; range, 12%-45%) and limited inhibition of downstream targets.
CONCLUSIONS
Although preclinical activity of MK-2206 can be demonstrated, this inhibitor has insufficient clinical antileukemia activity when given alone at tolerated doses, and alternative approaches to block AKT signaling should be explored.
Topics: Acute Disease; Administration, Oral; Adult; Aged; Aged, 80 and over; Apoptosis; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Exanthema; Female; HL-60 Cells; Heterocyclic Compounds, 3-Ring; Humans; Immunoblotting; Leukemia, Myeloid; Male; Middle Aged; Proto-Oncogene Proteins c-akt; Pruritus; Salvage Therapy; Treatment Outcome; U937 Cells
PubMed: 24583795
DOI: 10.1158/1078-0432.CCR-13-1978 -
Cureus Apr 2024Acute pancreatitis is a rare manifestation of acute myeloid leukemia which can be a presentation at the initial diagnosis or during or after the onset of the disease....
Acute pancreatitis is a rare manifestation of acute myeloid leukemia which can be a presentation at the initial diagnosis or during or after the onset of the disease. Acute myeloid leukemia occurs due to the abnormal proliferation of undifferentiated hematopoietic stem cells in the bone marrow which alter the normal hematopoiesis. We report the case of a 32-year-old male admitted with a one-month history of fever and backache, followed by 15 days of blackish stool discoloration and two days of abdominal pain and reduced urine output. On clinical examination, he was hypoxic with respiratory distress with epigastric tenderness. Blood investigations and imaging were consistent with acute pancreatitis. A complete blood count with peripheral smear showed severe normocytic normochromic anemia and an increased myeloid series containing 50% myeloblasts and 30% monoblasts. Additionally, some cells displayed cytoplasmic vacuolations, with a reticulocyte count of 2%. These findings were suggestive of acute myeloid leukemia M5. Due to the poor Glasgow Coma Scale (GCS), he was intubated and placed on mechanical ventilation. Unfortunately, he did not improve despite treatment and succumbed to the illness.
PubMed: 38803787
DOI: 10.7759/cureus.59108 -
Respiration; International Review of... 2011Pseudomonas aeruginosa is a cause of infections of the lower respiratory tract among patients with chronic lung disorders. It is questionable whether virulence of this... (Comparative Study)
Comparative Study
BACKGROUND
Pseudomonas aeruginosa is a cause of infections of the lower respiratory tract among patients with chronic lung disorders. It is questionable whether virulence of this species may be influenced by multidrug resistance (MDR).
OBJECTIVES
To define the impact of MDR in experimental lung infection.
METHODS
Experimental empyema was induced in rabbits by MDR (group A, n = 16) and by susceptible isolates (group B, n = 10). Pleural fluid was sampled for quantitative culture and estimation of cell apoptosis and of tumor necrosis factor-alpha (TNFα) and malondialdehyde (MDA). Survival was recorded. Cytokine production was stimulated in U937 monocytes by samples of pleural fluid. Whole blood of rabbits was incubated with the isolates; induction of apoptosis was assessed.
RESULTS
Survival of group A was prolonged compared to group B. This was accompanied by lower bacterial counts of the inoculated pathogens in pleural fluid and in the lungs of group A compared with group B. Early apoptosis of neutrophils of pleural fluid of group A was lower compared with group B. Pleural fluid concentrations of TNFα and MDA did not differ between the groups. Cytokine production by U937 monocytes after stimulation with pleural fluid was greater in group B than in group A. The susceptible isolate induced apoptosis of neutrophils in vitro at a greater rate than the MDR isolate.
CONCLUSIONS
Experimental empyema by susceptible P. aeruginosa is accompanied by greater mortality compared with MDR P. aeruginosa. This phenomenon may be attributed to the different growth pattern of the pathogens or to their interaction with the innate immune system.
Topics: Animals; Bacterial Load; Cytokines; Disease Susceptibility; Drug Resistance, Multiple, Bacterial; Empyema; Humans; Immunity, Innate; Lung; Male; Malondialdehyde; Monocytes; Neutrophils; Pleural Effusion; Pseudomonas Infections; Pseudomonas aeruginosa; Rabbits; Species Specificity; Survival Rate; Tumor Necrosis Factor-alpha; U937 Cells; Virulence
PubMed: 21525725
DOI: 10.1159/000326893 -
International Immunopharmacology Jun 2024Patients with diabetes are particularly susceptible to Legionella pneumophila (LP) infection, but the exact pathogenesis of LP infection in diabetic patients is still...
BACKGROUND
Patients with diabetes are particularly susceptible to Legionella pneumophila (LP) infection, but the exact pathogenesis of LP infection in diabetic patients is still not fully understood. Herein, we investigated the effect of diabetes on immune function during LP infection in vitro and in vivo.
METHODS
The time course of LP infection in macrophages under normal and high-glucose (HG) conditions was examined in vitro. Western blot was used to determine nucleotide-binding oligomerization domain 1 (NOD1), kinase 1/2 (ERK1/2), mitogen-activated protein kinase p38 (MAPK p38), and c-Jun N-terminal kinases (JNK). Enzyme-linked immunosorbent assay (ELISA) was used to assess the secretion of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Cell Counting Kit-8 (CCK8) assay assessed U937 cell viability after treating cells with different concentrations of high sugar medium and ML130 (NOD1 inhibitor). For the in vivo study, normal and streptozocin-induced diabetic guinea pigs were infected with LP for 6, 24, and 72 h, after which NOD1, MAPK-related signals, TNF-α, and IL-6 expression in lung tissues were assessed using immunohistochemistry, western blot, and RT-PCR.
RESULTS
HG attenuated the upregulation of NOD1 expression and reduced TNF-α and IL-6 secretion caused by LP compared with LP-infected cells exposed to normal glucose levels (all p < 0.05). In diabetic guinea pigs, HG inhibited the upregulation of NOD1 expression in lung tissues and the activation of p38, ERK1/2, and cJNK caused by LP infection compared to control pigs (all p < 0.05).
CONCLUSION
HG attenuates the response of macrophages to LP infection by inhibiting NOD1 upregulation and the activation of MAPK signaling.
Topics: Nod1 Signaling Adaptor Protein; Animals; Humans; Macrophages; Legionella pneumophila; Glucose; Guinea Pigs; Male; Interleukin-6; Legionnaires' Disease; Diabetes Mellitus, Experimental; MAP Kinase Signaling System; U937 Cells; Tumor Necrosis Factor-alpha; Mice
PubMed: 38749333
DOI: 10.1016/j.intimp.2024.112254 -
Biological & Pharmaceutical Bulletin Jul 2007Beta-sitosterol is the main dietary phytosterol found in plants and has been shown to inhibit proliferation and induce apoptosis in human solid tumors such as colon and...
Beta-sitosterol is the main dietary phytosterol found in plants and has been shown to inhibit proliferation and induce apoptosis in human solid tumors such as colon and breast cancers. However, the mechanism by which beta-sitosterol induces apoptosis is not completely understood in leukemic cells. This study investigated the mechanism of apoptosis induced by beta-sitosterol in human leukemic U937 cells. beta-Sitosterol induced cytotoxicity and apoptosis in U937 cells in a concentration dependent manner, as measured by hemocytometer counts, fluorescence microscopy, agarose gel electrophoresis, and flow cytometry analysis. The increase in apoptosis induced by beta-sitosterol was associated with down-regulation of Bcl-2, degradation of poly-(ADP-ribose) polymerase (PARP) and phospholipase C (PLC)-gamma1 protein, and activation of caspase-3. beta-Sitosterol induced apoptosis was not associated with changes in the expression of Bcl-xL, Bax, or inhibitor of apoptosis proteins (IAPs). z-DEVD-fmk, a caspase-3 specific inhibitor, blocked caspase-3 activation and PARP degradation, and significantly attenuated beta-sitosterol-induced apoptosis. This suggests that caspase-3 activation is partially essential for beta-sitosterol-induced apoptosis. Bcl-2 overexpression also significantly blocked caspase-3 activation and the decrease in PARP cleavage by beta-sitosterol, and effectively attenuated the apoptotic response to beta-sitosterol. These results show that beta-sitosterol potently induces apoptosis in U937 cells and that beta-sitosterol-induced apoptosis is related to the selective activation of caspase-3 and induction of Bax/Bcl-2 ratio.
Topics: Apoptosis; Caspase 3; Caspase Inhibitors; Cell Proliferation; Enzyme Activation; Humans; Proto-Oncogene Proteins c-bcl-2; Sitosterols; U937 Cells; bcl-2-Associated X Protein
PubMed: 17603173
DOI: 10.1248/bpb.30.1317 -
Zhonghua Xue Ye Xue Za Zhi = Zhonghua... May 2023To investigate the effect of the AML1-ETO (AE) fusion gene on the biological function of U937 leukemia cells by establishing a leukemia cell model that induces AE...
To investigate the effect of the AML1-ETO (AE) fusion gene on the biological function of U937 leukemia cells by establishing a leukemia cell model that induces AE fusion gene expression. The doxycycline (Dox) -dependent expression of the AE fusion gene in the U937 cell line (U937-AE) were established using a lentivirus vector system. The Cell Counting Kit 8 methods, including the PI and sidanilide induction, were used to detect cell proliferation, cell cycle-induced differentiation assays, respectively. The effect of the AE fusion gene on the biological function of U937-AE cells was preliminarily explored using transcriptome sequencing and metabonomic sequencing. ①The Dox-dependent Tet-on regulatory system was successfully constructed to regulate the stable AE fusion gene expression in U937-AE cells. ②Cell proliferation slowed down and the cell proliferation rate with AE expression (3.47±0.07) was lower than AE non-expression (3.86 ± 0.05) after inducing the AE fusion gene expression for 24 h (<0.05). The proportion of cells in the G(0)/G(1) phase in the cell cycle increased, with AE expression [ (63.45±3.10) %) ] was higher than AE non-expression [ (41.36± 9.56) %] (<0.05). The proportion of cells expressing CD13 and CD14 decreased with the expression of AE. The AE negative group is significantly higher than the AE positive group (<0.05). ③The enrichment analysis of the transcriptome sequencing gene set revealed significantly enriched quiescence, nuclear factor kappa-light-chain-enhancer of activated B cells, interferon-α/γ, and other inflammatory response and immune regulation signals after AE expression. ④Disorder of fatty acid metabolism of U937-AE cells occurred under the influence of AE. The concentration of the medium and short-chain fatty acid acylcarnitine metabolites decreased in cells with AE expressing, propionyl L-carnitine, wherein those with AE expression (0.46±0.13) were lower than those with AE non-expression (1.00±0.27) (<0.05). The metabolite concentration of some long-chain fatty acid acylcarnitine increased in cells with AE expressing tetradecanoyl carnitine, wherein those with AE expression (1.26±0.01) were higher than those with AE non-expression (1.00±0.05) (<0.05) . This study successfully established a leukemia cell model that can induce AE expression. The AE expression blocked the cell cycle and inhibited cell differentiation. The gene sets related to the inflammatory reactions was significantly enriched in U937-AE cells that express AE, and fatty acid metabolism was disordered.
Topics: Humans; U937 Cells; RUNX1 Translocation Partner 1 Protein; Leukemia; Core Binding Factor Alpha 2 Subunit; Oncogene Proteins, Fusion; Leukemia, Myeloid, Acute
PubMed: 37550185
DOI: 10.3760/cma.j.issn.0253-2727.2023.05.003 -
Cancer Immunology, Immunotherapy : CII Mar 2012Severe immune suppression is frequent in late-stage tumor patients and promotes tumor immune evasion and subsequent tumor progression. Regulatory T cells (Treg) are... (Clinical Trial)
Clinical Trial
Severe immune suppression is frequent in late-stage tumor patients and promotes tumor immune evasion and subsequent tumor progression. Regulatory T cells (Treg) are major suppressors of anti-tumor immune responses. Therefore, targeting of Treg has become a key goal of anti-tumor therapy. Several preclinical and clinical observations suggest that Treg can be depleted by cyclophosphamide. Over a period of 3 months, we investigated the effect of metronomic low-dose cyclophosphamide on Treg numbers, suppressive capacity and proliferation on endogenous anti-tumor T-cell responses and on their correlation to clinical outcome in 12 patients with treatment-refractory metastasized breast cancer who received single-agent 50 mg cyclophosphamide p.o. daily. Cyclophosphamide treatment initially caused a significant reduction in circulating Treg by more than 40% (P = 0.002). However, Treg numbers completely recovered during the treatment due to increased proliferative activity and maintained their suppressive capacity. Treg depletion coincided with a strong increase in breast tumor-reactive T cells (P = 0.03) that remained at high levels during the whole period. Numbers of tumor-reactive T cells but not of Treg correlated with disease stabilization (P = 0.03) and overall survival (P = 0.027). We conclude that metronomic low-dose cyclophosphamide only transiently reduces Treg but induces stable tumor-specific T-cell responses, which correlate with improved clinical outcome in advanced-stage breast cancer patients.
Topics: Adult; Aged; Antineoplastic Agents, Alkylating; Breast Neoplasms; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Cyclophosphamide; Dose-Response Relationship, Drug; Female; Humans; Interferon-gamma; Lymphocyte Count; Middle Aged; Neoplasm Metastasis; Survival Analysis; T-Lymphocytes, Cytotoxic; T-Lymphocytes, Regulatory; Time Factors; Treatment Outcome; U937 Cells
PubMed: 21915801
DOI: 10.1007/s00262-011-1106-3