Macrophage Cells (macrophage + cell)

Distribution by Scientific Domains

Terms modified by Macrophage Cells

  • macrophage cell line

  • Selected Abstracts


    Lycopene Inhibits LPS-Induced Proinflammatory Mediator Inducible Nitric Oxide Synthase in Mouse Macrophage Cells

    JOURNAL OF FOOD SCIENCE, Issue 1 2007
    Mohamed M. Rafi
    ABSTRACT:, Lycopene is a fat-soluble red-orange carotenoid found primarily in tomatoes and tomato-derived products, including tomato sauce, tomato paste, and ketchup, and other dietary sources, including dried apricots, guava, watermelon, papaya, and pink grapefruit. In this study, we have demonstrated the molecular mechanism underlying the anti-inflammatory properties of lycopene using a mouse macrophage cell line (RAW 264.7). Treatment with lycopene (10 ,M) inhibited lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production (40% compared with the control). Western blotting and reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that lycopene treatment decreased LPS-induced inducible nitric oxide synthase (iNOS) protein and mRNA expression in RAW 264.7 cells, respectively. These results suggest that lycopene has anti-inflammatory activity by inhibiting iNOS proteins and mRNA expressions in mouse macrophage cell lines. Furthermore, cyclooxygenase-2 (COX-2) protein and mRNA expression were not affected by treatment with lycopene. [source]


    Intracellular HMGB1 transactivates the human IL1B gene promoter through association with an Ets transcription factor PU.1

    EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2008
    Fumihiko Mouri
    Abstract High mobility group box 1 protein (HMGB1), originally described as a non-histone, DNA binding protein, was recently identified as a late mediator of inflammation via its extracellular release from activated macrophages/monocytes. In the present study, we report that intracellular HMGB1 synergizes with a macrophage/monocyte-specific E26 transformation-specific sequence (Ets) transcription factor PU.1 to transactivate the promoter of the IL1B gene coding a 31-kDa proIL-1, protein. The ,131 to +12 IL1B promoter, which possesses a PU.1 binding motif essential for its transactivation, was induced when HMGB1 expression vector was transfected into murine RAW264.7 macrophage cells. Our glutathione S -transferase-pulldown and coimmunoprecipitation assays demonstrated direct physical interaction of HMGB1 with PU.1. Deletion of the PU.1 winged helix-turn-helix DNA-binding domain inhibited the association of the two proteins. In electrophoretic mobility shift assay using recombinant PU.1 protein, a ternary complex of PU.1, HMGB1 and PU.1-binding element within the IL1B promoter was generated. The importance of PU.1 was further supported by our observation that induction of the IL1B promoter was obtained only after PU.1 expression in PU.1-deficient murine EL4 thymoma cells. Thus, our data raise the possibility of a novel mechanism which sustains and amplifies inflammatory reactions through physical interaction of PU.1 with intracellular HMGB1 in macrophages/monocytes. [source]


    Fluorescent Nanoprobes: Fluorescent Gold Nanoprobe Sensitive to Intracellular Reactive Oxygen Species (Adv. Funct.

    ADVANCED FUNCTIONAL MATERIALS, Issue 12 2009
    Mater.
    On page 1884, H. Lee and co-workers report fluorescent gold nanoprobes sensitive to reactive oxygen species (ROS). Using nanoparticle surface energy transfer between gold nanoparticles and end-dopamine modified fluorescein-hyaluronic acid conjugates, gold nanoprobes are created with extreme sensitivity to intracellular ROS. The cover image shows real time monitoring of intracellular ROS generation within macrophage cells via fluorescence recovery of the nanoprobes. [source]


    Altered immune response to CNS viral infection in mice with a conditional knock-down of macrophage-lineage cells

    GLIA, Issue 2 2006
    Jessica Carmen
    Abstract Neuroadapted Sindbis Virus (NSV) is a neuronotropic virus that causes hindlimb paralysis in susceptible mice and rats. The authors and others have demonstrated that though death of infected motor neurons occurs, bystander death of uninfected neurons also occurs and both contribute to the paralysis that ensues following infection. The authors have previously shown that the treatment of NSV-infected mice with minocycline, an inhibitor that has many functions within the central nervous system (CNS), including inhibiting microglial activation, protects mice from paralysis and death. The authors, therefore, proposed that microglial activation may contribute to bystander death of motor neurons following NSV infection. Here, the authors tested the hypothesis using a conditional knock-out of activated macrophage-lineage cells, including endogenous CNS macrophage cells. Surprisingly, ablation of these cells resulted in more rapid death and similar weakness in the hind limbs of NSV-infected animals compared with that of control animals. Several key chemokines including IL-12 and monocyte chemoattractant protein-1 (MCP-1) did not become elevated in these animals, resulting in decreased infiltration of T lymphocytes into the CNS of the knock-down animals. Either because of the decreased macrophage activation directly or because of the reduced immune cell influx, viral replication persisted longer within the nervous system in knock-down mice than in wild type mice. The authors, therefore, conclude that although macrophage-lineage cells in the CNS may contribute to neurodegeneration in certain situations, they also serve a protective role, such as control of viral replication. © 2006 Wiley-Liss, Inc. [source]


    Heparinized Magnetic Nanoparticles: In-Vitro Assessment for Biomedical Applications,

    ADVANCED FUNCTIONAL MATERIALS, Issue 13 2006
    C. Wuang
    Abstract Superparamagnetic magnetite nanoparticles are of great interest owing to their numerous existing and potential biomedical applications. In this study, superparamagnetic magnetite nanoparticles with average diameters of 6,8,nm have been prepared and surface-functionalized with poly(N -isopropylacrylamide) (poly(NIPAAM)) via a surface-initiated atom-transfer radical polymerization, followed by immobilization of heparin. The success of the various surface-functionalization steps has been ascertained using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The rate of internalization of the as-synthesized and surface-functionalized magnetite nanoparticles by mouse macrophage cells has been investigated. The nanoparticle internalization into the macrophages has been visualized using optical microscopy and quantified by inductively coupled plasma spectroscopy. The effectiveness of the heparinized nanoparticles in preventing thrombosis has been determined using the plasma recalcification time. The results indicate that the above-mentioned surface modifications of the magnetite nanoparticles are effective in delaying phagocytosis and preventing blood clotting in vitro. Such properties can be expected to enable their use in biomedical applications. [source]


    Enhanced Osteoclastogenesis in 4-1BB,Deficient Mice Caused by Reduced Interleukin-10,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2006
    Hyun-Hee Shin PhD
    Abstract Enhanced osteoclastogenesis was observed in bone marrow,derived macrophage cells from 4-1BB,deficient mice than in those from wildtype mice. 4-1BB and 4-1BB ligand interaction may play a role at a certain stage of osteoclast formation through increased level of IL-10, a negative regulator of osteoclastogenesis. Introduction: 4-1BB is an inducible T-cell costimulatory molecule and a member of the TNF receptor family. The expression pattern of 4-1BB and 4-1BB ligand (4-1BBL) has suggested that 4-1BB plays a role not only in various responses related to innate immunity but also in bone metabolism. Materials and Methods: Osteoclast formation was evaluated in bone marrow,derived macrophage cells (BMMs) from wildtype and 4-1BB,deficient (4-1BB,/,) mice. Expression of interleukin-10 (IL-10) during osteoclast formation was analyzed at the mRNA and protein levels. Results: Expression of IL-10 was higher in RANKL-stimulated wildtype BMMs than 4-1BB,/, BMMs. When 4-1BBL was stimulated with 4-1BB,Fc fusion protein, the expression of IL-10 in BMMs increased. Neutralization of IL-10 was not as effective in preventing inhibition by IL-10 of osteoclast differentiation in 4-1BB,/, BMMs as in wildtype BMMs. When IL-10 was added to the culture medium, osteoclast formation was inhibited more efficiently in the 4-1BB,/, BMMs than in the wildtype BMMs. Conclusions: Interaction of 4-1BB and 4-1BBL stimulates IL-10 production through 4-1BBL signaling. 4-1BBL plays a role at a certain stage of osteoclast formation, and IL-10 may mediate this effect. The elevated level of osteoclastogenesis in 4-1BB,/, BMMs may thus be caused, in part, by a lower level of IL-10. [source]


    Effect of High Pressure Pasteurization on Bacterial Load and Bioactivity of Echinacea Purpurea

    JOURNAL OF FOOD SCIENCE, Issue 7 2010
    Xiu-Min Chen
    Abstract:, High hydrostatic pressure (HHP) technology was applied to organic Echinacea purpurea (E. purpurea) roots and flowers to determine the feasibility of using this technology for cold herb pasteurization, to produce microbiologically safe and shelf-stable products for the natural health products (NHPs) industry. HHP significantly (P < 0.01) reduced microbial contamination in both roots and flowers without affecting the phytochemical retention of chicoric and chlorogenic acids, and total alkamide contents. The antioxidant activity of E. purpurea methanol-derived extracts, evaluated in both chemical (2,2,-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) [ABTS] and oxygen radical absorption capacity [ORAC] assay) and in cell culture models (RAW264, 7 macrophage, H2O2 -induced intracellular oxidation, and lipopolysaccharide [LPS]-induced nitric oxide production), was not adversely affected by the application of HHP at both 2 and 5 min at 600 mPa. Furthermore, HHP did not affect the capacity of E. purpurea extracts to suppress nitric oxide production in LPS-activated macrophage cells. Therefore, our results show that HHP is an effective pasteurization process treatment to reduce microbial-contamination load while not adversely altering chemical and bioactive function of active constituents present in organic E. purpurea. Practical Application:, Our study reports for the first time, the effectiveness of using high hydrostatic pressure (HHP) technology pressure to pasteurize E. purpurea root and flower, and the comparative retention of bioactive phytochemicals. Therefore, this technique can be used in food and natural health product industries to produce high-quality, microbiologically safe, and shelf-stable products. [source]


    Real-time monitoring of the membrane-binding and insertion properties of the cholesterol-dependent cytolysin anthrolysin O from Bacillus anthracis,

    JOURNAL OF MOLECULAR RECOGNITION, Issue 4 2006
    Simon Cocklin
    Abstract Bacillus anthracis has recently been shown to secrete a potently hemolytic/cytolytic protein that has been designated anthrolysin O (ALO). In this work, we initiated a study of this potential anthrax virulence factor in an effort to understand the membrane,binding properties of this protein. Recombinant anthrolysin O (rALO35,512) and two N-terminally truncated versions of ALO (rALO390,512 and rALO403,512) from B. anthracis were overproduced in Escherichia coli and purified to homogeneity. The role of cholesterol in the cytolytic activity of ALO was probed in cellular cholesterol depletion assays using mouse and human macrophage-like lines, and also Drosophila Schneider 2 cells. Challenging the macrophage cells with rALO35,512, but not rALO390,512 or rALO403,512, resulted in cell death by lysis, with this cytolysis being abolished by depletion of the membrane cholesterol. Drosophila cells, which contain ergosterol as their major membrane sterol, were resistant to rALO-mediated cytolysis. In order to determine the molecular mechanism of this resistance, the interaction of rALO with model membranes comprised of POPC alone, or with a variety of structurally similar sterols including ergosterol, was probed using Biacore. Both rALO35,512 and rALO403,512 demonstrated robust binding to model membranes composed of POPC and cholesterol, with amount of protein bound proportional to the cholesterol content. Ergosterol supported greatly reduced binding of both rALO35,512 and rALO403,512, whereas other sterols tested did not support binding. The rALO403,512,membrane interaction demonstrated an equilibrium dissociation constant (KD) in the low nanomolar range, whereas rALO35,512 exhibited complex kinetics likely due to the multiple events involved in pore formation. These results establish the pivotal role of cholesterol in the action of rALO. The biosensor method developed to measure ALO recognition of cholesterol in a membrane environment could be extended to provide a platform for the screening of inhibitors of other membrane-binding proteins and peptides. Copyright© 2006 John Wiley & Sons, Ltd. [source]


    Bis-(3-hydroxyphenyl) diselenide inhibits LPS-stimulated iNOS and COX-2 expression in RAW 264.7 macrophage cells through the NF- kB inactivation

    JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2009
    Kyung-Min Shin
    Abstract Objectives Previously, we reported that diaryl diselenide compounds have strong inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophages. In this study, we investigated the molecular mechanisms underlying NO suppression and prostaglandin E2 (PGE2) production by diaryl diselenide compounds, bis-(2-hydroxyphenyl) diselenide (DSE-A), bis-(3-hydroxyphenyl) diselenide (DSE-B), bis-(4-hydroxyphenyl) diselenide (DSE-C), dipyridyl diselenide (DSE-D) and diphenyl diselenide (DSE-E). Methods The effect of these compounds on NO suppression and PGE2 production was investigated in RAW 264.7 macrophages. Key findings Our data indicate that of the above, DSE-B most potently inhibits NO and PGE2 production, and that it also significantly reduces the releases of tumour necrosis factor (TNF)-,, interleukin(IL)-1, and IL-6. Consistent with these observations, DSE-B also reduced the protein levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), and the mRNA levels of iNOS, COX-2, TNF-,, IL-1, and IL-6. Furthermore, DSE-B inhibited LPS-induced nuclear factor-,B (NF-,B) activation, which was associated with the prevention of the inhibitor ,B-, (I,B-,) degradation and a subsequent reduction in nuclear p65 protein levels. Conclusions Taken together, our data suggest that the anti-inflammatory properties of DSE-B are due to reduction in the expression of iNOS, COX-2, TNF-,, IL-1, and IL-6 through the down-regulation of NF-,B binding activity. [source]


    Anti-angiogenic, antinociceptive and anti-inflammatory activities of Lonicera japonica extract

    JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2008
    Hye-Jung Yoo
    This study aimed to elucidate some novel pharmacological activities of Lonicera japonica (Caprifoliaceae), which is widely used in Oriental folk medicine. The ethanolic extract of L. japonica (LJ) dose dependently inhibited chick chorioallantoic membrane angiogenesis. The antinociceptive activity of LJ was assessed using the acetic acid-induced constriction model in mice. LJ showed anti-inflammatory activity in two in-vivo models: the vascular permeability and air pouch models. LJ suppressed the production of nitric oxide via down-regulation of inducible nitric oxide synthase in lipopolysaccharide-stimulated RAW264.7 macrophage cells. However, LJ was unable to suppress induction of cyclooxygenase-2 in the stimulated macrophage cells. LJ decreased the reactive oxygen species level in the stimulated macrophage cells. In brief, the flowers of L. japonica possess potent anti-angiogenic and antinociceptive activities, in addition to anti-inflammatory activity, which partly supports its therapeutic efficacy. [source]


    Radical scavenging and anti-inflammatory activity of extracts from Opuntia humifusa Raf.

    JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 1 2006
    J. Y. Cho
    Opuntia humifusa Raf. (O. humifusa Raf.) is a member of the Cactaceae family. To determine the antioxidative and anti-inflammatory effects of this herb, various solvent fractions (methanol, hexane, chloroform, ethyl acetate, butanol, and water) prepared from the leaves of cacti were tested using DPPH (2,2-diphenyl-l-picrylhydrazyl radical) and xanthine oxidase assays, and nitric oxide (NO)-producing macrophage cells. We found that O. humifusa Raf. displayed potent antioxidative and anti-inflammatory activity. Thus, all solvent fractions, except for the water layer, showed potent scavenging effects. The scavenging effect of the ethyl acetate fraction was higher than that of the other fractions, with IC50 values of 3.6 and 48.2 ,g mL,1. According to activity-guided fractionation, one of the active radical scavenging principles in the ethyl acetate fraction was found to be quercetin. In contrast, only two fractions (chloroform and ethyl acetate) significantly suppressed nitric oxide production from the lipopolysaccharide (LPS)-activated RAW264.7 cells. In addition, chloroform and ethyl acetate fractions significantly blocked the expression of inducible nitric oxide synthetase (iNOS) and interleukin-6 (IL-6) from the RAW264.7 cells stimulated by LPS. Moreover, ethyl acetate fractions significantly blocked the expression of IL-1, from the RAW264.7 cells stimulated by LPS. Therefore, the results suggested that O. humifusa Raf. may modulate radical-induced toxicity via both direct scavenging activity and the inhibition of reactive species generation, and the modulation of the expression of inflammatory cytokines. Finally, O. humifusa Raf. may be useful as a functional food or drug against reactive species-mediated disease. [source]


    Enhanced protection by melatonin and meloxicam combination in experimental infection by Trypanosoma cruzi

    PARASITE IMMUNOLOGY, Issue 4 2010
    L. G. R. OLIVEIRA
    Summary The aim of this study was to evaluate a possible synergism between melatonin and meloxicam in up-regulating the immune response in male Wistar rats infected with Trypanosoma cruzi during immunosuppression phenomenon, which characterizes the acute phase of the Chagas' disease. Male Wistar rats were infected with the Y strain of T. cruzi. Experiments were performed on 7, 14 and 21 days post-infection. Several immunological parameters were evaluated including ,-interferon (IFN-,), interleukin-2 (IL-2), nitric oxide (NO) and prostaglandin E2 (PGE2). The combined treatment with melatonin and meloxicam significantly enhanced the release of IL-2 and INF-, into animals' serum, when compared with the infected control groups during the course of infection. Furthermore, the blockade of PGE2 synthesis and the increased release of NO by macrophage cells from T. cruzi -infected animals contributed to regulate the production of Th1 subset cytokines significantly reducing the parasitaemia in animals treated with the combination of both substances. Therefore, our results suggest that the association of melatonin and meloxicam was more effective in protecting animals against the harmful actions of T. cruzi infection as compared with the treatments of meloxicam or melatonin alone. [source]


    In vitro induction of nitric oxide synthase in astrocytes and microglia by Trypanosoma brucei brucei

    PARASITE IMMUNOLOGY, Issue 1 2000
    Murielle Girard
    In stage II human african trypanosomiasis (HAT), which is characterized by central nervous system (CNS) involvement, neurones and oligodendrocytes might be targets of dysimmune processes. Nitric oxide (NO) production by peripheral macrophages is documented in HAT. We studied the production of NO by murine astrocytes and microglia cocultured with Trypanosoma brucei(T. b.) brucei AnTat 1.9. Purified astrocytes or microglia from mouse brains were cocultured with T. b. brucei, and in some instances with interferon (IFN)-,, which is known to be released during the disease and also to be a growth factor for trypanosomes. Inducible NO synthase (iNOS) expression was studied by indirect immunofluorescence and reverse transcriptase-polymerase chain reaction. NO production was determined by measuring nitrite generation in culture. Detection of iNOS in astrocytes and microglia in the presence of T. b. brucei, was closely associated with nitrite production and was strongly enhanced by the addition of IFN-, to the culture medium. The stimulation of iNOS activity required parasite,cell contact and likely occurred at the transcriptional level. This study demonstrates the induction of iNOS in CNS-related macrophage cells in the presence of trypanosomes and its potentiation by IFN-,. [source]


    Features of chronic allograft rejection on rat small intestine transplantation

    PEDIATRIC TRANSPLANTATION, Issue 2 2007
    Hao Ma
    Abstract:, The aim of this study was to develop a model of chronic rejection of the entire small intestine transplantation and to analyze the features of chronic rejection. Allogenic small bowel transplantation was performed in a rat combination of Lewis to F344. Intestines were procured at the 60th and the 90th day after operation. We compared the semiquantitative score of histological parameters. The immunological components involved in the chronic rejection process were evaluated by immunohistochemical staining and the cytokine levels in grafts. The significant characteristics of the allograft on histology were changes of villous architecture, interstitial fibrosis, leukocyte infiltration, and obliterative arteriopathy. Allografts on the 60th day post-transplantation had more score in inflammatory events, while the grafts on the 90th day after operation had more values in ischemia/fibrotic events. The number of infiltrating CD4, CD8 and macrophage cells in allografts progressively decreased over time. The level of intrgraft cytokines such as IL-6, TNF- , and IL-10 in the 90th day after transplantation also decreased compared with that in the 60th day. These data suggested that in the early stage (POD 60), there were more active and intense inflammatory events; later (POD 90) allografts manifested less inflammation and more arterial obliteration and fibrosis. [source]


    Review article: Is obesity an inflammatory illness?

    BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 10 2006
    Role of low-grade inflammation, macrophage infiltration in human white adipose tissue
    There are at least two scientific evidences of human obesity as a chronic inflammatory illness: first, the well-described moderate increase of inflammatory factors in the circulation in obese subjects, and second, the recent identification of macrophage cells infiltrating the white adipose tissue (WAT). These observations led to a revision of the physiopathology of obesity and its co-morbidities. It has been suggested that the ,low-grade' inflammatory state associates with metabolic and cardiovascular complications of obesity. Weight loss is able to improve this inflammatory state by both significantly decreasing circulating inflammatory molecules and macrophage cell infiltration in WAT depots. However, the mechanisms of WAT macrophage recruitment into the adipose tissue and their role in obesity complications have not been defined. This review aims to point out the knowledge on inflammatory cytokines associated with obesity and focuses on macrophage infiltration in human WAT, discussing their recruitment and role. The interactions of macrophages with adipocytes will certainly be the subject of intense investigations in the future. [source]


    Omega-3 polyunsaturated fatty acids ameliorate the severity of ileitis in the senescence accelerated mice (SAM)P1/Yit mice model

    CLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2009
    H. Matsunaga
    Summary Clinical studies using omega-3 polyunsaturated fatty acids (,3-PUFA) to Crohn's disease (CD) are conflicting. Beneficial effects of dietary ,3-PUFA intake in various experimental inflammatory bowel disease (IBD) models have been reported. However, animal models of large intestinal inflammation have been used in all previous studies, and the effect of ,3 fat in an animal model of small intestinal inflammation has not been reported. We hypothesized that the effects of ,3 fat are different between large and small intestine. The aim of this study was to determine whether the direct effect of ,3 fat is beneficial for small intestinal inflammation. Senescence accelerated mice (SAM)P1/Yit mice showed remarkable inflammation of the terminal ileum spontaneously. The numbers of F4/80-positive monocyte,macrophage cells as well as ,7-integrin-positive lymphocytes in the intestinal mucosa were increased significantly compared with those in the control mice (AKR-J mice). The area of mucosal addressin cell adhesion molecule-1 (MAdCAM-1)-positive vessels was also increased. The degree of expression levels of monocyte chemoattractant protein-1 (MCP-1), interleukin (IL)-6 and interferon (IFN)-, mRNA were increased significantly compared with those in the control mice. The feeding of two different kinds of ,3 fat (fish-oil-rich and perilla-oil-rich diets) for 16 weeks to SAMP1/Yit mice ameliorated inflammation of the terminal ileum significantly. In both the ,3-fat-rich diet groups, enhanced infiltration of F4/80-positive monocytes/macrophages in intestinal mucosa of SAMP1/Yit mice cells and the increased levels of MCP-1, IL-6 and IFN-, mRNA expression were ameliorated significantly compared with those in the control diet group. The results suggest that ,3 fat is beneficial for small intestinal inflammation by inhibition of monocyte recruitment to inflamed intestinal mucosa. [source]


    Myelin transcription factor 1 (Myt1) expression in demyelinated lesions of rodent and human CNS

    GLIA, Issue 7 2007
    Adam C. Vana
    Abstract Myelin transcription factor 1 (Myt1) is a zinc-finger DNA binding protein that influences developing oligodendrocyte progenitor (OP) cell proliferation, differentiation, and myelin gene transcription in vitro. The potential of Myt1 to play a role in OP responses leading to remyelination was examined using murine hepatitis virus strain A59 (MHV) to induce spinal cord demyelination and potential relevance to human pathology was evaluated in multiple sclerosis (MS) lesions. In MHV-infected mice, the density of Myt1 expressing cells markedly increased in lesioned areas of spinal cord white matter. Myt1 expressing cells proliferated most extensively during active demyelination and subsequently accumulated to maximal levels during early remyelination. Cells with nuclear Myt1 immunoreactivity were mainly OP cells, identified by co-localization with platelet-derived growth factor alpha receptor, with additional phenotypes being either oligodendrocytes or neural stem cells, identified by CC1 antigen and Musashi1, respectively. The density of OP cells expressing Myt1 was significantly increased in white matter of MHV-infected mice during demyelination and early remyelination then as remyelination advanced the values returned to levels comparable to PBS-injected control mice. In MHV lesions, Myt1 was not expressed in astrocytes, lymphocytes, or macrophage/microglial cells. MS lesions demonstrated increased Myt1 expression in both the periplaque white matter adjacent to lesions and within early remyelinating lesions. These results suggesta potential role for Myt1 in the regeneration of oligodendrocyte lineage cells in response to demyelination. © 2007 Wiley-Liss, Inc. [source]


    Proteomic identification of an upregulated isoform of annexin A3 in the rat brain following reversible cerebral ischemia

    GLIA, Issue 16 2007
    Heike Junker
    Abstract We used proteomics to identify regulated proteins following cerebral ischemia in a rat model. Young rats were subjected to reversible middle cerebral artery (MCA) occlusion and proteins were extracted from the peri-infarcted and the corresponding contralateral area at days 3 and 14 postischemia. Proteins were analyzed by two-dimensional polyacrylamide gel electrophoresis followed by mass spectrometry. We report for the first time that an isoform of annexin A3 (ANXA3) was among the upregulated proteins in the postischemic rat brain. The results were confirmed by real-time PCR and by western blotting. Double- and triple-immunostaining with neuronal and microglia/macrophagic markers demonstrated that ANXA3 is produced by resting microglia in control tissue and by activated microglial/macrophage cells in the infarcted area. 3D-images of the infarcted area suggest that ANXA3 is associated with a phagocytic phenotype. Our study identifies ANXA3 as a novel marker of brain microglia, which should be of substantial value in future studies of microglial cells and its role in the postischemic brain. © 2007 Wiley-Liss, Inc. [source]


    Neurotrophin Receptor-like Proteins in the Bovine (Bos taurus) Lymphoid Organs, with Special Reference to Thymus and Spleen

    ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2001
    M. B. Levanti
    Increasing evidence suggests that neurotrophins could regulate immune functions acting directly or indirectly on immunocompetent cells. The indirect pathway involves stromal cells of the primary and secondary lymphoid organs. In the present study the occurrence of Trk proteins (TrkA, TrkB and TrkC), regarded as the high-affinity signal-transducing receptors for neurotrophins, was investigated in cow lymphoid organs using immunohistochemistry. The thymus and spleen of both fetal and adult animals, and the palatine tonsils, lymph nodes and Peyer's patches of adult animals, were analysed. Unidentified cells displaying TrkA-like immunoreactivity were found in the fetal thymus, whereas those expressing this protein in the adult gland were identified as epithelial cells. In the spleen, immunoreactive TrkA was observed in cells of the white pulp. TrkB immunoreactivity in both fetal and adult thymus and spleen was localized in monocyte/macrophage cells. As a rule, TrkC was absent from the thymus and the spleen independent of the animal's age. Different types of stromal cells, but never the lymphocytes themselves, displayed TrkA, TrkB, or TrkC immunoreactivity in the other lymphoid organs analysed. As in other vertebrate species, Trk proteins in the lymphoid organs of the cow were localized in the stromal, non-lymphoid cells, thus suggesting that neurotrophins might regulate the immune function acting indirectly on lymphocytes. [source]