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Haematologica Dec 2014CXC chemokine receptor 4 (CXCR4) is an essential regulator for homing and maintenance of hematopoietic stem cells within the bone marrow niches. Analysis of clinical... (Comparative Study)
Comparative Study
CXC chemokine receptor 4 (CXCR4) is an essential regulator for homing and maintenance of hematopoietic stem cells within the bone marrow niches. Analysis of clinical implications of bone marrow CXCR4 expression in patients with acute myeloid leukemia showed not only higher CXCR4 expression was an independent poor prognostic factor, irrespective of age, white blood cell counts, cytogenetics, and mutation status of NPM1/FLT3-ITD and CEBPA, but also showed CXCR4 expression was inversely associated with mutations of CEBPA, a gene encoding transcription factor C/EBPα. Patients with wild-type CEBPA had significantly higher CXCR4 expression than those with mutated CEBPA. We hypothesized that CEBPA might influence the expression of CXCR4. To test this hypothesis, we first examined endogenous CXCR4 expression in 293T and K562 cells over-expressing wild-type C/EBPα p42 and demonstrated that CXCR4 levels were increased in these cells, whilst the expression of the N-terminal mutant, C/EBPα p30, diminished CXCR4 transcription. We further showed p42 was bound to the CXCR4 promoter by the chromatin immunoprecipitation assays. Induction of p42 in the inducible K562-C/EBPα cell lines increased the chemotactic migration. Moreover, decreased expression of C/EBPα by RNA interference decreased levels of CXCR4 protein expression in U937 cells, thereby abrogating CXCR4-mediated chemotaxis. Our results provide, for the first time, evidence that C/EBPα indeed regulates the activation of CXCR4, which is critical for the homing and engraftment of acute myeloid leukemia cells, while p30 mutant impairs CXCR4 expression.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Blotting, Western; Bone Marrow; CCAAT-Enhancer-Binding Proteins; Case-Control Studies; Chemotaxis; Cohort Studies; Female; Flow Cytometry; Follow-Up Studies; Gene Expression Regulation, Neoplastic; Hematopoietic Stem Cells; Humans; K562 Cells; Leukemia, Myeloid, Acute; Male; Middle Aged; Mutation; Neoplasm Recurrence, Local; Neoplasm Staging; Nucleophosmin; Prognosis; Promoter Regions, Genetic; RNA, Messenger; RNA, Small Interfering; Real-Time Polymerase Chain Reaction; Receptors, CXCR4; Reverse Transcriptase Polymerase Chain Reaction; Survival Rate; U937 Cells; Young Adult
PubMed: 25193961
DOI: 10.3324/haematol.2014.107821 -
International Journal of Radiation... Aug 2015Radiation-induced heart disease (RIHD) is a delayed effect of radiotherapy for cancers of the chest, such as breast, esophageal, and lung. Kinins are small peptides with...
PURPOSE
Radiation-induced heart disease (RIHD) is a delayed effect of radiotherapy for cancers of the chest, such as breast, esophageal, and lung. Kinins are small peptides with cardioprotective properties. We previously used a rat model that lacks the precursor kininogen to demonstrate that kinins are involved in RIHD. Here, we examined the role of the kinin B2 receptor (B2R) in early radiation-induced signaling in the heart.
MATERIALS AND METHODS
Male Brown Norway rats received the B2R-selective antagonist HOE-140 (icatibant) via osmotic minipump from 5 days before until 4 weeks after 21 Gy local heart irradiation. At 4 weeks, signaling events were measured in left ventricular homogenates and nuclear extracts using western blotting and real-time polymerase chain reaction. Numbers of CD68-positive (monocytes/macrophages), CD2-positive (T-lymphocytes), and mast cells were measured using immunohistochemistry.
RESULTS
Radiation-induced c-Jun phosphorylation and nuclear translocation were enhanced by HOE-140. HOE-140 did not modify endothelial nitric oxide synthase (eNOS) phosphorylation or alter numbers of CD2-positive or mast cells, but enhanced CD68-positive cell counts in irradiated hearts.
CONCLUSIONS
B2R signaling may regulate monocyte/macrophage infiltration and c-Jun signals in the irradiated heart. Although eNOS is a main target for kinins, the B2R may not regulate eNOS phosphorylation in response to radiation.
Topics: Animals; Heart; Heart Diseases; Male; Myocardium; Radiation Dosage; Radiation Injuries; Radiotherapy; Rats; Receptor, Bradykinin B2
PubMed: 25955317
DOI: 10.3109/09553002.2015.1047041 -
British Journal of Experimental... Oct 1979The deposition of quartz in the pulmonary alveoli creates a major demand for macrophages to replace those destroyed, but local proliferation of monocytes appeared to be...
The deposition of quartz in the pulmonary alveoli creates a major demand for macrophages to replace those destroyed, but local proliferation of monocytes appeared to be minimal and the role of systemic recruitment was therefore explored. Injected silica and lipids stimulated the phagocytic function of the mononuclear phagocytic system (MPS), whilst inhaled silica provoked lipid accumulation in the lung, thus suggesting that lipid might also induce a proliferative response in the marrow. Using marrow cultures, cells of the rat MPS were identified by size and phagocytic capacity for latex microspheres, and then subjected to kinetic analysis in litter-mate pairs by single and double labelling autoradiography, under normal conditions and after administration of lipid extracted from rat lungs consolidated by silica-induced alveolar lipo-proteinosis. Treatment of the results by a new device facilitated distinction of promonocytes from monocytes and thus afforded a more precise means of assessing MPS kinetics. The duration of DNA synthesis and the cell-cycle time of promonocytes were reduced and the rate of entry into DNA synthesis increased as a result of i.v. injection of lung lipid. These findings support the involvement of systemic recruitment of monocytes from the marrow by a positive feed-back mechanism when a powerful irritant persists in the lungs and the results are discussed in the overall context of silicotic fibrogenesis.
Topics: Animals; Bone Marrow Cells; Cell Count; Feedback; Kinetics; Lipids; Macrophages; Male; Mitosis; Phagocytosis; Pulmonary Alveoli; Rats; Silicosis
PubMed: 518823
DOI: No ID Found -
Respiratory Research Mar 2013Marked accumulation of alveolar macrophages (AM) conferred by apoptosis resistance has been implicated in pathogenesis of chronic obstructive pulmonary disease (COPD)....
BACKGROUND
Marked accumulation of alveolar macrophages (AM) conferred by apoptosis resistance has been implicated in pathogenesis of chronic obstructive pulmonary disease (COPD). Apoptosis inhibitor of macrophage (AIM), has been shown to be produced by mature tissue macrophages and AIM demonstrates anti-apoptotic property against multiple apoptosis-inducing stimuli. Accordingly, we attempt to determine if AIM is expressed in AM and whether AIM is involved in the regulation of apoptosis in the setting of cigarette smoke extract (CSE) exposure.
METHODS
Immunohistochemical evaluations of AIM were performed. Immunostaining was assessed by counting total and positively staining AM numbers in each case (n = 5 in control, n = 5 in non-COPD smoker, n = 5 in COPD). AM were isolated from bronchoalveolar lavage fluid (BALF). The changes of AIM expression levels in response to CSE exposure in AM were evaluated. Knock-down of anti-apoptotic Bcl-xL was mediated by siRNA transfection. U937 monocyte-macrophage cell line was used to explore the anti-apoptotic properties of AIM.
RESULTS
The numbers of AM and AIM-positive AM were significantly increased in COPD lungs. AIM expression was demonstrated at both mRNA and protein levels in isolated AM, which was enhanced in response to CSE exposure. AIM significantly increased Bcl-xL expression levels in AM and Bcl-xL was involved in a part of anti-apoptotic mechanisms of AIM in U937 cells in the setting of CSE exposure.
CONCLUSIONS
These results suggest that AIM expression in association with cigarette smoking may be involved in accumulation of AM in COPD.
Topics: Aged; Antigens, CD; Antigens, Differentiation, T-Lymphocyte; Apoptosis Regulatory Proteins; Bronchoalveolar Lavage Fluid; Cells, Cultured; Female; Gene Expression Regulation; HEK293 Cells; Humans; Lectins, C-Type; Macrophages, Alveolar; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive; U937 Cells
PubMed: 23497247
DOI: 10.1186/1465-9921-14-30 -
The Anatomical Record Nov 1997Milky spots in the human greater omentum are preformed specific accumulations of primarily macrophages within the stroma of the greater omentum. To obtain a better...
BACKGROUND
Milky spots in the human greater omentum are preformed specific accumulations of primarily macrophages within the stroma of the greater omentum. To obtain a better understanding of milky spots in the human greater omentum, the development and the earliest forms of milky spots in the human greater omentum were studied, with special attention to the macrophage population.
METHODS
Specimens of human greater omentum were obtained from fetuses of 20 to 40 weeks gestation and one newborn three days old (n = 6). Using mature macrophages (RFD 7), activated macrophages (RFD 1), B-lymphocytes (CD 22), and T-lymphocytes (CD 2), and immunoperoxydase labeling, the percentage of these cells in developing milky spots and the development of milky spots were studied by light microscopy. A time-dependent increase in the percentage of positive staining cells and the size of clusters was analyzed using the non-parametric Spearman rank correlation test.
RESULTS
Small accumulations of cells with about 50% monocytes/macrophages were present at 20 weeks of gestation. With increasing gestational age the number of clusters of cells increased significantly (P < 0.01) as well as their size (P < 0.01). Starting at 29 weeks, vascularized clusters of cells were seen; true milky spots were present at 35 weeks. A significant (P < 0.05) increase in the percentage of mature macrophages was found in developing milky spots, whereas no activated macrophages were seen. The percentage of B-lymphocytes and T-lymphocytes found in the clusters of cells and milky spots increased significantly (P < 0.05) but did not exceed 10% of the total number of cells.
CONCLUSIONS
From our data it can be concluded that milky spots are specific structures in the greater omentum formed between the 20th and 35th week of gestation. Further, we concluded that immature cells (promonocytes) mature locally in developing milky spots.
Topics: Cell Aggregation; Cell Count; Embryo, Mammalian; Embryonic and Fetal Development; Humans; Immunohistochemistry; Lymphocytes; Macrophages; Omentum; Staining and Labeling
PubMed: 9372174
DOI: 10.1002/(SICI)1097-0185(199711)249:3<399::AID-AR11>3.0.CO;2-J -
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 -
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