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American Journal of Reproductive... Aug 2020The state of self-renewal and self-maintain of decidual macrophages would be important for immune homeostasis at the maternal-fetal interface. The roles of interleukin...
PROBLEM
The state of self-renewal and self-maintain of decidual macrophages would be important for immune homeostasis at the maternal-fetal interface. The roles of interleukin (IL)-24 derived from decidual stromal cells (DSCs) on decidual macrophages have not been explored.
METHOD OF STUDY
IL-24 expression in DSCs was interfered by lentivirus, and the transcription levels of IL-24 in DSCs were verified by real time (RT)-PCR. The levels of IL-24 receptors were determined by flow cytometry assays. The effect of recombination human IL-24 (rhIL-24) on the differentiation and apoptosis of macrophages was analyzed by flow cytometry in vitro. The viability of macrophages was detected by Cell Counting Kit-8 assays.
RESULTS
The growth of DSCs was not affected obviously only by IL-24 knockdown while the growth of knockdown DSCs was inhibited significantly after co-cultured with decidual macrophages. The levels of IL-24 receptors (IL-20R1 and IL-22R1) were moderately to highly expressed on decidual macrophages and human macrophage cell line U937. The differentiation of decidual macrophages treated by rhIL-24 or co-cultured with IL-24 knockdown DSCs was not affected. Both apoptosis and viability of U937 cells were promoted by rhIL-24. The ratio of Bcl-2/Bax was down-regulated and Ki-67 was up-regulated by IL-24 treatment. The expression of Bcl-2/Bax was up-regulated while Ki-67 was down-regulated in U937 cells after co-cultured by IL-24 knockdown DSCs.
CONCLUSION
IL-24 secreted by DSCs promotes the renewal and homeostasis of decidual macrophages possibly via down-regulating the ratio of Bcl-2/Bax and up-regulating of the expression of Ki-67 in early pregnancy.
Topics: Adult; Apoptosis; Cell Differentiation; Cell Self Renewal; Decidua; Female; Gene Knockdown Techniques; Homeostasis; Humans; Interleukins; Macrophages; Pregnancy; Proto-Oncogene Proteins c-bcl-2; Stromal Cells; U937 Cells; Young Adult; bcl-2-Associated X Protein
PubMed: 32356306
DOI: 10.1111/aji.13261 -
Cytometry. Part B, Clinical Cytometry Nov 2018The purpose of this study was to determine whether immunophenotypic profiles detected by flow cytometry are useful in differentiating chronic myelomonocytic leukemia...
OBJECTIVES
The purpose of this study was to determine whether immunophenotypic profiles detected by flow cytometry are useful in differentiating chronic myelomonocytic leukemia (CMML) from reactive monocytosis, and between CMML subtypes.
METHODS
Eight-color flow cytometry was used to immunophenotype blasts, monocytes, and granulocytes in the bone marrow of 34 patients with CMML and 12 patients with reactive monocytosis.
RESULTS
Bone marrow myeloblast, promonocyte, and monocyte counts by flow cytometry were significantly higher in the CMML group than in the reactive monocytosis group. Myeloblast aberrancies were present in all CMML patients as compared with 2 of 12 (16.7%) reactive monocytosis patients (P < 0.001). The number of blast aberrancies ranged from one to nine (median, four) in CMML patients and 94.1% of CMML cases exhibited ≥ two aberrancies. In contrast, two reactive monocytosis cases showed only one phenotypic abnormality of blasts. Monocyte and granulocyte aberrancies were present in 26 of 34 (76.5%) and in 31 of 34 (91.2%) CMML patients, respectively. Decreased side scatter (SSC) and abnormal CD11b/CD13/CD16 maturation pattern in granulocytes were more frequent in CMML than in reactive monocytosis. No significant differences in antigen expression were detected between the CMML subtypes except that altered CD45/SSC pattern on the blasts was more commonly observed in CMML-0/1 than in CMML-2.
CONCLUSIONS
CMML has phenotypic aberrancies in monocytes, granulocytes, and more frequently in myeloblasts. Aberrant expression of two or more antigens in myeloblasts by flow cytometry has a high sensitivity (94.1%) and a high specificity (100%) to differentiate CMML from reactive monocytosis. © 2018 International Clinical Cytometry Society.
Topics: Adult; Aged; Aged, 80 and over; Female; Flow Cytometry; Humans; Immunophenotyping; Leukemia, Myelomonocytic, Chronic; Male; Middle Aged; Monocytes; Young Adult
PubMed: 30334354
DOI: 10.1002/cyto.b.21721 -
Scientific Reports Jul 2020Loss of estrogens at menopause is a major cause of osteoporosis and increased fracture risk. Estrogens protect against bone loss by decreasing osteoclast number through...
Loss of estrogens at menopause is a major cause of osteoporosis and increased fracture risk. Estrogens protect against bone loss by decreasing osteoclast number through direct actions on cells of the myeloid lineage. Here, we investigated the molecular mechanism of this effect. We report that 17β-estradiol (E) decreased osteoclast number by promoting the apoptosis of early osteoclast progenitors, but not mature osteoclasts. This effect was abrogated in cells lacking Bak/Bax-two pro-apoptotic members of the Bcl-2 family of proteins required for mitochondrial apoptotic death. FasL has been previously implicated in the pro-apoptotic actions of E. However, we show herein that FasL-deficient mice lose bone mass following ovariectomy indistinguishably from FasL-intact controls, indicating that FasL is not a major contributor to the anti-osteoclastogenic actions of estrogens. Instead, using microarray analysis we have elucidated that ERα-mediated estrogen signaling in osteoclast progenitors decreases "oxidative phosphorylation" and the expression of mitochondria complex I genes. Additionally, E decreased the activity of complex I and oxygen consumption rate. Similar to E, the complex I inhibitor Rotenone decreased osteoclastogenesis by promoting osteoclast progenitor apoptosis via Bak/Bax. These findings demonstrate that estrogens decrease osteoclast number by attenuating respiration, and thereby, promoting mitochondrial apoptotic death of early osteoclast progenitors.
Topics: Adenosine Triphosphate; Animals; Apoptosis; Biomarkers; Bone Density; Bone and Bones; Cell Count; Cell Differentiation; Cells, Cultured; Estrogens; Female; Gene Expression Regulation; Mice; Mice, Knockout; Mitochondria; Monocyte-Macrophage Precursor Cells; Osteoclasts; Osteogenesis; Oxidative Phosphorylation; Signal Transduction
PubMed: 32686739
DOI: 10.1038/s41598-020-68890-7 -
Developmental and Comparative Immunology Aug 2010Recently, it has been reported that Salmonella secrete flagellin in response to host produced lysophospholipids. However, this monomer of the bacterial flagella...
Recently, it has been reported that Salmonella secrete flagellin in response to host produced lysophospholipids. However, this monomer of the bacterial flagella activates Toll-like receptor 5 (TLR5) in the innate immune system. The objective of this study was to examine the role of flagellin expression during infection of species-specific macrophages (MPhi) which either expressed or lacked TLR5. Initially, TLR5-activity was confirmed in bovine MPhi using Salmonella typhimurium derived-flagellin. Within these cells, recombinant FliC induced a potent CXCL8 response when compared to the heterogeneous (FliC/FljB) form of purified flagellin. Furthermore, neither form of flagellin induced nitrite secretion which was subsequently detected after exposing bovine MPhi to LPS in the presence of IFN-gamma. Flagellin enhanced the accumulation of Salmonella enteritidis in TLR5-positive bovine and human MPhi which was independent of adhesion in bovine MPhi. In contrast, murine MPhis which lacked TLR5 were equally susceptible to hosting S. enteritidis, with or without flagellin. However, lack of flagellin in S. typhimurium marginally inhibited bacterial accumulation in bovine MPhi, where FljB and FliC compensated for the lack of each other. This study suggests that flagellin may be inducing TLR5-dependent internalisation mechanisms in Mcapital EF, Cyrillic which vary qualitatively between different species and Salmonella serotypes.
Topics: Animals; Cattle; Colony Count, Microbial; Flagellin; Humans; Immunity, Innate; Immunization; Interleukin-8; Lipopolysaccharides; Macrophages; Salmonella Infections; Salmonella enteritidis; Salmonella typhimurium; Species Specificity; Toll-Like Receptor 5; Tumor Necrosis Factor-alpha; U937 Cells
PubMed: 20188752
DOI: 10.1016/j.dci.2010.02.008 -
Contrast Media & Molecular Imaging Nov 2016Cellular MRI, which visualizes magnetically labelled cells (cells*), is an active research field for in vivo cell therapy and tracking. The simultaneous relaxation rate...
Cellular MRI, which visualizes magnetically labelled cells (cells*), is an active research field for in vivo cell therapy and tracking. The simultaneous relaxation rate measurements (R *, R , R ) are the basis of a quantitative cellular MRI method proposed here. U937 cells were labelled with Molday ION Rhodamine B, a bi-functional superparamagnetic and fluorescent nanoparticle (U937*). U937* viability and proliferation were not affected in vitro. In vitro relaxometry was performed in a cell concentration range of [2.5 × 10 -10 ] cells/mL. These measurements show the existence of complementary cell concentration intervals where these rates vary linearly. The juxtaposition of these intervals delineates a wide cell concentration range over which one of the relaxation rates in a voxel of an in vivo image can be converted into an absolute cell concentration. The linear regime was found at high concentrations for R in the range of [10 - 2 × 10 ] cells/mL, at intermediate concentrations for R in [2.5 × 10 - 5 × 10 ] cells/mL and at low concentrations for R * in [8 × 10 - 5 × 10 ] cells/mL. In vivo relaxometry was performed in a longitudinal study, with labelled U937 cells injected into a U87 glioma mouse model. Using in vitro data, maps of in vivo U937* concentrations were obtained by converting one of the in vivo relaxation rates to cell concentration maps. MRI results were compared with the corresponding optical images of the same brains, showing the usefulness of our method to accurately follow therapeutic cell biodistribution in a longitudinal study. Results also demonstrate that the method quantifies a large range of magnetically labelled cells*. Copyright © 2016 John Wiley & Sons, Ltd.
Topics: Animals; Brain; Cell Count; Cell Movement; Cell Transplantation; Fluorescence; Glioma; Heterografts; Humans; Magnetic Resonance Imaging; Magnetics; Mice; U937 Cells
PubMed: 27766757
DOI: 10.1002/cmmi.1715 -
Acta Haematologica 1975Monocytopoiesis was analyzed in patients with severe, acute inflammations induced by surgical interventions as well as in others with mild, chronic inflammations in...
Monocytopoiesis was analyzed in patients with severe, acute inflammations induced by surgical interventions as well as in others with mild, chronic inflammations in connection with gastric or duodenal ulcers. The state of acute inflammation was assumed to be associated with a high and steeply rising monocyte demand as opposed to the constant and relatively small monocyte recruitment in chronic inflammation. In chronic mild inflammatory reactions DNA synthesis activity of promonocytes was increased by a factor of about two; the promonocyte pool was normal. In patients who underwent surgical operations changes in the following parameters were observed during the first 15 h after start of surgery: (1) average increase in 3H-TDR labelling index by 38%; (2) average enlargement of promonocyte pool by 34%, (3) and relase of immature cells from the bone marrow into the blood. Increase in DNA synthesis activity as well as expansion of the promonocyte pool causes an enhanced monocyte production rate. The 'shift to the left' in monocyte egress is equivalent to a reduced stem-cell-to-blood transit time. These variations permit short-term adaptation of monocytopoiesis to varying demands.
Topics: Acute Disease; Adult; Cell Nucleus; Chronic Disease; DNA; Duodenal Ulcer; Hematopoiesis; Humans; Inflammation; Leukocyte Count; Middle Aged; Monocytes; Postoperative Complications; Stomach Ulcer
PubMed: 812318
DOI: 10.1159/000208094 -
Molecular Medicine Reports Sep 2015Neutrophil elastase (NE) is an early myeloid-specific serine protease, which is predominantly produced by promyelocytes. A previous study demonstrated that NE has an...
Neutrophil elastase (NE) is an early myeloid-specific serine protease, which is predominantly produced by promyelocytes. A previous study demonstrated that NE has an important role in the development of acute promyelocytic leukemia (APL). The process of APL was shown to be accelerated in animals that expressed abundant NE, whereas NE‑deficient mice were protected from APL development; thus suggesting an important role for NE in the development of APL. The present study aimed to investigate the effects and possible mechanisms of NE. Up- and downregulation of NE in various leukemia cell lines was conducted in order to explore its significance in the occurrence and procession of leukemia, with the aim of identifying novel targeted therapeutic drugs for the treatment of leukemia. NE was overexpressed in cells following infection with an adenovirus, and Cell Counting kit‑8 and flow cytometry results demonstrated that cell proliferation was promoted, and cell apoptosis was inhibited, as compared with the untreated cells. NE was downregulated in the cells by both RNA interference and treatment with GW311616A, a specific inhibitor of NE, following which cell growth was shown to be inhibited and apoptosis was induced. These results suggested that NE may promote the development of APL, therefore, NE may be a therapeutic target and its inhibitor GW311616A may be a potential therapeutic drug for leukemia. Furthermore, the apoptosis‑associated protein B‑cell lymphoma 2 (Bcl‑2)‑associated X protein was significantly increased, whereas Bcl‑2 was markedly decreased in the cells with downregulated NE. Further experiments revealed that the probable apoptosis‑associated signaling pathway was the phosphoinositide 3‑kinase/AKT pathway. The present study is the first, to the best of our knowledge, to demonstrate that GW311616A, a specific NE inhibitor, may act as a potential targeted drug for leukemia, which may have a profound impact on the future of leukemia-targeted therapy.
Topics: Apoptosis; Cell Line, Tumor; Cell Proliferation; Down-Regulation; Humans; K562 Cells; Leukemia, Promyelocytic, Acute; Leukocyte Elastase; Phosphatidylinositol 3-Kinases; Piperidines; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; RNA Interference; RNA, Small Interfering; Signal Transduction; U937 Cells; Up-Regulation; bcl-2-Associated X Protein
PubMed: 26081156
DOI: 10.3892/mmr.2015.3946 -
Journal of Microbiology (Seoul, Korea) Aug 2019Low-density lipoprotein (LDL) was recently reported to be an opsonin, enhancing the phagocytosis of group A Streptococcus (GAS) by human monocytic leukemia U937 cells...
Low-density lipoprotein (LDL) was recently reported to be an opsonin, enhancing the phagocytosis of group A Streptococcus (GAS) by human monocytic leukemia U937 cells due to the binding of LDL to some GAS strains. We postulated that LDL might also promote the opsonophagocytosis of Pseudomonas aeruginosa by U937 cells since this bacterium interacts with LDL. In this study, P. aeruginosa (CMCC10104), U937 cells, and human LDL were used in phagocytosis assays to test our hypothesis. Escherichia coli strain BL21, which does not interact with LDL, was used as a negative control. Colony counting and fluorescence microscopy were used to determine the bacterial quantity in the opsonophagocytosis assays. After incubation of U937 cells and P. aeruginosa with LDL (100 µg/ml) for 15 and 30 min, phagocytosis was observed to be increased by 22.71% and 32.90%, respectively, compared to that seen in the LDL-free group. However, LDL did not increase the phagocytosis of E. coli by U937 cells. In addition, we identified CD36 as a major opsonin receptor on U937 cells, since an anti-CD36 monoclonal antibody, but not an anti-CD4 monoclonal antibody, almost completely abolished the opsonophagocytosis of P. aeruginosa by U937 cells.
Topics: Antibodies, Monoclonal; Escherichia coli; Humans; Lipoproteins, LDL; Opsonin Proteins; Phagocytosis; Pseudomonas aeruginosa; U937 Cells
PubMed: 31089970
DOI: 10.1007/s12275-019-8413-3 -
Inflammation Apr 2015In previous studies, selenium (Se) was reported to play critical roles in anti-inflammatory activities. Nevertheless, limited information could be obtained during...
In previous studies, selenium (Se) was reported to play critical roles in anti-inflammatory activities. Nevertheless, limited information could be obtained during inflammation about selenomethionine (SeMet) in U937 human macrophage cells. The purpose of this study was to investigate the effects of SeMet on the inflammatory responses to lipopolysaccharide (LPS)-induced U937 macrophage cells and the signaling pathways targeted. U937 cells were pretreated with SeMet (1 μM) and subsequently induced with LPS (1 μg/ml) for 24 h. In the cell counting kit-8 assay (CCK-8), SeMet significantly inhibits the proliferation of U937 cells. SeMet also inhibited the production of nitric oxide (NO) and prostaglandin E2 (PGE2) stimulated by LPS. In the Western blot assay and real-time polymerase chain reaction (RT-PCR), SeMet significantly reduced protein expression and production of inducible NO synthase (iNOS), tumor necrosis factor-alpha (TNF-α), and COX-2 in U937 cells. Furthermore, SeMet markedly suppressed the LPS-mediated activation of nuclear factor-kappa B (NF-κB) by blocking the degradation of inhibitor-κB proteins (IκBα) and lessening the translocations of P50 subunit content of NF-κB in the nucleus. These findings suggested the anti-inflammatory activity of SeMet in U937 cells; indicating that SeMet might be a potential treatment for inflammation therapy.
Topics: Anti-Inflammatory Agents; Cell Survival; Dose-Response Relationship, Drug; Humans; Lipopolysaccharides; NF-kappa B; Selenomethionine; Signal Transduction; U937 Cells
PubMed: 25145772
DOI: 10.1007/s10753-014-9984-0 -
Rheumatology International Jun 2002The anti-inflammatory action of low-dose methoxetrate (MTX) in the treatment of rheumatoid arthritis (RA) appears to be partially impaired by folate supplementation....
OBJECTIVE
The anti-inflammatory action of low-dose methoxetrate (MTX) in the treatment of rheumatoid arthritis (RA) appears to be partially impaired by folate supplementation. Here we investigated whether a folate excess impairs monocyte differentiation, a putative anti-inflammatory action of low-dose MTX.
METHODS
Monocyte differentiation of U937 promonocytic cells was assessed by CD11b and CD14 immunostaining and fluorescent absorbent cell sorting (FACS) analysis. Cell proliferation and viability were determined by cell counts and trypan-blue staining, respectively. Nuclear apoptosis was assessed by 7-actinomycin staining. Cells were treated with 10(-10)-10(-6) M MTX in the presence or absence of folinic acid. Exposure to 1,25-OH-vitamine D(3) and TGF-beta served as a positive control of monocyte differentiation in U937 cells.
RESULTS
Low-dose MTX-induced monocyte differentiation was marginal when compared with 1,25-OH-D(3) + TGF-beta treatment. Low-dose MTX inhibited cell proliferation, induced apoptosis, and reduced cell viability. All the antiproliferative, cytotoxic, and monocyte differentiating effects of MTX were completely reversed by folinic acid.
CONCLUSIONS
Monocyte differentiation is part of the folate-dependent MTX actions.
Topics: Antirheumatic Agents; Apoptosis; CD11 Antigens; Calcitriol; Cell Differentiation; Cell Division; Cell Survival; Dose-Response Relationship, Drug; Drug Antagonism; Flow Cytometry; Humans; Leucovorin; Lipopolysaccharide Receptors; Methotrexate; Monocytes; Stem Cells; Tumor Cells, Cultured
PubMed: 12070677
DOI: 10.1007/s00296-002-0188-9