266 research outputs found

    amda 2 13 a major update for automated cross platform microarray data analysis

    Get PDF
    Microarray platforms require analytical pipelines with modules for data pre-processing including data normalization, statistical analysis for identification of differentially expressed genes, cluster analysis, and functional annotation. We previously developed the Automated Microarray Data Analysis (AMDA, version 2.3.5) pipeline to process Affymetrix 3′ IVT GeneChips. The availability of newer technologies that demand open-source tools for microarray data analysis has impelled us to develop an updated multi-platform version, AMDA 2.13. It includes additional quality control metrics, annotation-driven (annotation grade of Affymetrix NetAffx) and signal-driven (Inter-Quartile Range) gene filtering, and approaches to experimental design. To enhance understanding of biological data, differentially expressed genes have been mapped into KEGG pathways. Finally, a more stable and user-friendly interface was designed to integrate the requirements for different platforms. AMDA 2.13 allows the analysis of Affymetrix..

    Antibodies to myelin oligodendrocyte glycoprotein in idiopathic optic neuritis

    Get PDF
    Objectives: To investigate the differences of clinical features, cerebrospinal fluid (CSF), MRI findings and response to steroid therapies between patients with optic neuritis (ON) who have myelin oligodendrocyte glycoprotein (MOG) antibodies and those who have seronegative ON. Setting: We recruited participants in the department of neurology and ophthalmology in our hospital in Japan. Methods: We retrospectively evaluated the clinical features and response to steroid therapies of patients with ON. Sera from patients were tested for antibodies to MOG and aquaporin-4 (AQP4) with a cell-based assay. Participants: Between April 2009 and March 2014, we enrolled serial 57 patients with ON (27 males, 30 females; age range 16-84 years) who ophthalmologists had diagnosed as having or suspected to have ON with acute visual impairment and declined critical flicker frequency, abnormal findings of brain MRI, optical coherence tomography and fluorescein fundus angiography at their onset or recurrence. We excluded those patients who fulfilled the diagnostic criteria of neuromyelitis optica (NMO)/NMO spectrum disorders (NMOSD), MS McDonald\u27s criteria, and so on. Finally we defined 29 patients with idiopathic ON (14 males, 15 females, age range 16-84 years). Results: 27.6% (8/29) were positive for MOG antibodies and 3.4% (1/29) were positive for AQP4. Among the eight patients with MOG antibodies, five had optic pain (p=0.001) and three had prodromal infection (p=0.179). Three of the eight MOG-positive patients showed significantly high CSF levels of myelin basic protein (p=0.021) and none were positive for oligoclonal band in CSF. On MRIs, seven MOG-positive patients showed high signal intensity on optic nerve, three had a cerebral lesion and one had a spinal cord lesion. Seven of the eight MOG-positive patients had a good response to steroid therapy. Conclusions: Although not proving primary pathogenicity of anti-MOG antibodies, the present results indicate that the measurement of MOG antibodies is useful in diagnosing and treating ON

    Defining the role of NG2-expressing cells in experimental models of multiple sclerosis. A biofunctional analysis of the neurovascular unit in wild type and NG2 null mice

    Get PDF
    During experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis associated with blood-brain barrier (BBB) disruption, oligodendrocyte precursor cells (OPCs) overexpress proteoglycan nerve/glial antigen 2 (NG2), proliferate, and make contacts with the microvessel wall. To explore whether OPCs may actually be recruited within the neurovascular unit (NVU), de facto intervening in its cellular and molecular composition, we quantified by immunoconfocal morphometry the presence of OPCs in contact with brain microvessels, during postnatal cerebral cortex vascularization at postnatal day 6, in wildtype (WT) and NG2 knock-out (NG2KO) mice, and in the cortex of adult naive and EAE-affected WT and NG2KO mice. As observed in WT mice during postnatal development, a higher number of juxtavascular and perivascular OPCs was revealed in adult WT mice during EAE compared to adult naive WT mice. In EAE-affected mice, OPCs were mostly associated with microvessels that showed altered claudin-5 and occludin tight junction (TJ) staining patterns and barrier leakage. In contrast, EAE-affected NG2KO mice, which did not show any significant increase in vessel-associated OPCs, seemed to retain better preserved TJs and BBB integrity. As expected, absence of NG2, in both OPCs and pericytes, led to a reduced content of vessel basal lamina molecules, laminin, collagen VI, and collagen IV. In addition, analysis of the major ligand/receptor systems known to promote OPC proliferation and migration indicated that vascular endothelial growth factor A (VEGF-A), platelet-derived growth factor-AA (PDGF-AA), and the transforming growth factor-beta (TGF-beta) were the molecules most likely involved in proliferation and recruitment of vascular OPCs during EAE. These results were confirmed by real time-PCR that showed Fgf2, Pdgfa and Tgfb expression on isolated cerebral cortex microvessels and by dual RNAscope-immunohistochemistry/ in situ hybridization (IHC/ISH), which detected Vegfa and Vegfr2 transcripts on cerebral cortex sections. Overall, this study suggests that vascular OPCs, in virtue of their developmental arrangement and response to neuroinflammation and growth factors, could be integrated among the classical NVU cell components. Moreover, the synchronized activation of vascular OPCs and pericytes during both BBB development and dysfunction, points to NG2 as a key regulator of vascular interactions

    Characterization of mouse spinal cord vascular network by means of synchrotron radiation X-ray phase contrast tomography

    Get PDF
    High resolution Synchrotron-based X-ray Phase Contrast Tomography (XPCT) allows the simultaneous detection of three dimensional neuronal and vascular networks without using contrast agents or invasive casting preparation. We show and discuss the different features observed in reconstructed XPCT volumes of the ex vivo mouse spinal cord in the lumbo-sacral region, including motor neurons and blood vessels. We report the application of an intensity-based segmentation method to detect and quantitatively characterize the modification in the vascular networks in terms of reduction in experimental visibility. In particular, we apply our approach to the case of the experimental autoimmune encephalomyelitis (EAE), i.e. human multiple sclerosis animal model

    Immunolocalization of CCL2-expressing cells in EAE and EAE-MSC cerebral cortex

    Get PDF
    The chemokine CCL2 has been considered as a mediator of inflammation in different diseases of the central nervous system, including experimental autoimmune encephalomyelitis (EAE), where the chemokine mediates extravasation of mononuclear leukocytes and loss of microvessel barrier function [1]. Previous studies have demonstrated that cellular sources of CCL2 during both EAE and multiple sclerosis (MS) are astrocytes and microvessel endothelial cells (ECs). Initially, we have demonstrated that in a MOG-induced model of EAE in C57BL/6 mice, 6 hrs after the intravenous treatment with bone marrow derived mesenchymal stem cells (MSCs) [2], the junctional staining patter of blood-brain barrier (BBB) microvessels and their functional effectiveness to permeability tracers seem to be restored. We have subsequently analysed, in the same experimental models, EAE and EAE-MSC mice, expression and immunolocalization of chemokine CCL2 by double immmunolabelling with cell-specific markers: endothelial PECAM-1 (CD31), OPCs (oligodendrocyte precursor cells) proteoglycan NG2, astrocytic GFAP, and Iba1 for microglia cells. Surprisingly, in the adopted model of cerebral cortex EAE, astrocytes and ECs do not show any detectable CCL2 expression, instead a strong staining is observed on activated parenchymal and perivascular microglia. Astrogliosis, microglia activation, and CCL2 overexpression appearing strongly reduced in EAE mice after MSC treatment. These observations identify microglia cells as the major source of CCL2 in EAE mice, whose barrier is damaged, and suggest the downregulation of the chemokine in perivascular microglia as a possible mechanism involved in BBB protection after MSC administration

    BBB-endothelial tight junction response to mesenchymal stem cells in a model of MOG EAE

    Get PDF
    Experimental autoimmune encephalomyelitis (EAE), an induced autoimmune disease of the central nervous system, simulates the main histopathological and clinical aspects of multiple sclerosis including the impairment of the blood-brain barrier (BBB). In several experimental models of human neurodegenerative diseases, the intravenous (iv) injection of bone marrow-derived mesenchymal stem cells (MSCs) ameliorates clinical symptoms and histopathological features [1,2]. On the basis of these data, we have analyzed the status of BBB tight junctions (TJs) of cerebral cortex microvessels in a model of MOG-EAE with iv injection of MSCs (EAE-MSC). The observations were carried out on EAE-MSC mice sacrificed at 6-24 hrs and 10 days after MSCs iv injection. The expression of endothelial TJ proteins, claudin-5 and occludin, was analyzed in healthy, EAE, and EAE-MSC mice by immunofluorescence confocal microscopy, together with the evaluation of barrier function by FITC-Dextran, as an exogenous permeability tracer. The results demonstrate that unlike EAE animals, characterized by an interrupted junctional staining and a barrier leakage, EAE-MSC mice show together with attenuate disease symptoms, a continuous, control- like claudin-5 and occludin junctional pattern and a functionally recovered barrier efficiency. Overall, these findings suggest that during EAE, the neuroprotective effect of the injected MSCs includes a reparative BBB response that in turn may contribute to the reduction of the inflammatory infiltrates and to the significant amelioration of the disease

    Dysregulation of regulatory CD56bright NK cells/T cells interactions in multiple sclerosis

    Get PDF
    Recent evidence has shown that CD56bright NK cells, a subset of NK cells abundant in lymph nodes, may have an immunoregulatory function. In multiple sclerosis (MS), expansion of CD56bright NK cells has been associated to successful response to different treatments and to remission of disease during pregnancy; how whether they exert immunoregulation in physiologic conditions and whether this is impaired in MS is not known. We dissected the immunoregulatory role of CD56bright NK cells function in healthy subjects (HS) and compared it with that of untreated MS subjects or patients with clinically isolated syndrome suggestive of MS (CIS). We found that CD56bright NK cells from HS acquire, upon inflammatory cues, the capability of suppressing autologous CD4+T cell proliferation through direct cytotoxicity requiring engagement of natural cytotoxicity receptors (NCRs) and secretion of granzyme B. CD56bright NK cells from patients with MS/CIS did not differ in frequency and share a similar phenotype but displayed a significantly lower ability to inhibit autologous T cell proliferation. This impairment was not related to deficient expression of NCRs or granzyme B by CD56bright NK cells, but to increased HLA-E expression on T cells from MS/CIS subjects, which could enhance the inhibitory effect mediated by NKG2A that is homogeneously expressed on CD56bright NK cells. The defect in controlling autologous T cells by CD56bright NK cells in MS/CIS might contribute to the excess of autoimmune response that is associated to disease development
    corecore