Background: Multiple sclerosis (MS) is a neuroinflammatory demyelinating disease characterized by motor deficits and cognitive decline. Many immune aspects of the disease are understood through studies in the experimental autoimmune encephalomyelitis (EAE) model, including the contribution of the NF-κB transcription factor to neuroinflammation. However, the cell-specific roles of NF-κB to EAE and its cognitive comorbidities still needs further investigation.
View Article and Find Full Text PDFSince 2010, the West Nile virus (WNV) has been established in Greece. We describe the epidemiology of diagnosed human WNV infections in Greece with a focus on the 2022 season. During the transmission period, clinicians were sending samples from suspected cases for testing.
View Article and Find Full Text PDFEuro Surveill
July 2023
After the near absence of influenza and other respiratory viruses during the first 2 years of the COVID-19 pandemic, an increased activity of mainly influenza A(H3N2) was detected at the beginning of August 2022 in Greece on three islands. Of 33 cases with respiratory symptoms testing negative for SARS-CoV-2 with rapid antigen tests, 24 were positive for influenza: 20 as A(H3N2) subtype and four as A(H1N1)pdm09 subtype. Phylogenetic analysis of selected samples from both subtypes was performed and they fell into clusters within subclades that included the 2022/23 vaccine strains.
View Article and Find Full Text PDFAutoimmune diseases affecting the CNS not only overcome immune privilege mechanisms that protect neural tissues but also peripheral immune tolerance mechanisms towards self. Together with antigen-specific T cells, myeloid cells are main effector cells in CNS autoimmune diseases such as multiple sclerosis, but the relative contributions of blood-derived monocytes and the tissue resident macrophages to pathology and repair is incompletely understood. Through the study of oxidized mannan-conjugated myelin oligodendrocyte glycoprotein 35-55 (OM-MOG), we show that peripheral maturation of Ly6CCCR2 monocytes to Ly6CMHCIIPD-L1 cells is sufficient to reverse spinal cord inflammation and demyelination in MOG-induced autoimmune encephalomyelitis.
View Article and Find Full Text PDFAutotaxin (ATX; ) is a secreted lysophospholipase D catalyzing the extracellular production of lysophosphatidic acid (LPA), a pleiotropic signaling phospholipid. Genetic and pharmacologic studies have previously established a pathologic role for ATX and LPA signaling in pulmonary injury, inflammation, and fibrosis. Here, increased mRNA levels were detected in immune cells from nasopharyngeal swab samples of COVID-19 patients, and increased ATX serum levels were found in severe COVID-19 patients.
View Article and Find Full Text PDFMeasles virus (MeV) has a negative-sense 15 kb long RNA genome, which is generally conserved. Recent advances in high-throughput sequencing (HTS) and Dual RNA-seq allow the analysis of viral RNA genomes and the discovery of viral infection biomarkers, via the simultaneous characterization of the host transcriptome. However, these host-pathogen interactions remain largely unexplored in MeV infections.
View Article and Find Full Text PDFCNS autoantigens conjugated to oxidized mannan (OM) induce antigen-specific T cell tolerance and protect mice against autoimmune encephalomyelitis (EAE). To investigate whether OM-peptides treat EAE initiated by human MHC class II molecules, we administered OM-conjugated murine myelin oligodendrocyte glycoprotein peptide 35-55 (OM-MOG) to humanized HLA-DR2b transgenic mice (DR2b.Ab°), which are susceptible to MOG-EAE.
View Article and Find Full Text PDFBetween May 2017 and November 2018, Greece has experienced a severe measles outbreak with a total of 3258 cases reported, after reaching its goal of eliminating measles since 2014-2015. In this study, we aimed to investigate the origin and the dispersal patterns of the measles strains that circulated in Greece during this outbreak and to identify possible transmission patterns of measles virus (MeV) in the country. Of the 832 measles suspect cases referred to the National Measles and Rubella Reference Laboratory for MeV RNA detection, 131 randomly selected positive samples, representative of the temporal and spatial distribution of the laboratory-confirmed measles cases in Greece, were processed for genotypic identification by an RT-PCR amplification of a 598 bp fragment containing the 450 bp hypervariable region of the measles virus N gene.
View Article and Find Full Text PDFCurrent virus detection methods often take significant time or can be limited in sensitivity and specificity. The increasing frequency and magnitude of viral outbreaks in recent decades has resulted in an urgent need for diagnostic methods that are facile, sensitive, rapid and inexpensive. Here, we describe and characterise a novel, calcium-mediated interaction of the surface of enveloped viruses with DNA, that can be used for the functionalisation of intact virus particles via chemical groups attached to the DNA.
View Article and Find Full Text PDFMesenchymal stem cells (MSC) provide therapeutic effects in experimental CNS disease models and show promise as cell-based therapies for humans, but their modes of action are not well understood. We previously show that MSC protect rodent neurons against glutamate excitotoxicity in vitro, and in vivo in an epilepsy model. Neuroprotection is associated with reduced NMDA glutamate receptor (NMDAR) subunit expression and neuronal glutamate-induced calcium (Ca) responses, and increased expression of stem cell-associated genes.
View Article and Find Full Text PDFAnti-DNA cell-penetrating autoantibodies have been extensively studied in autoimmune but not in normal sera. We investigated herein the presence and properties of cell-penetrating antibodies (CPAbs) in intravenous immunoglobulin (IVIg), a blood product of pooled normal human IgG. IVIg cell penetration was observed into various cell lines, as well as cells from several organs of mice injected intravenously with IVIg therapeutic dose.
View Article and Find Full Text PDFAlthough interferon-β is used as first-line therapy for multiple sclerosis, the cell type-specific activity of type I interferons in multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis, remains obscure. In this study, we have elucidated the in vivo immunomodulatory role of type I interferon signaling in T cells during experimental autoimmune encephalomyelitis by use of a novel transgenic mouse, carrying a cd2-ifnar1 transgene on a interferon-α/β receptor 1 null genetic background, thus allowing expression of the interferon-α/β receptor 1 and hence, a functional type I interferon receptor exclusively on T cells. These transgenic mice exhibited milder experimental autoimmune encephalomyelitis with reduced T cell infiltration, demyelination, and axonal damage in the central nervous system.
View Article and Find Full Text PDFExperimental autoimmune encephalomyelitis (EAE) is a valuable model for studying immunopathology in multiple sclerosis (MS) and for exploring the interface between autoimmune responses and CNS tissue that ultimately leads to lesion development. In this study, we measured gene expression in mouse spinal cord during myelin oligodendrocyte gp35-55 peptide-induced EAE, using quantitative RT-PCR, to identify gene markers that monitor individual hallmark pathological processes. We defined a small panel of genes whose longitudinal expression patterns provided insight into the timing, interrelationships, and mechanisms of individual disease processes and the efficacy of therapeutics for the treatment of MS.
View Article and Find Full Text PDFMultiple antigenic peptide (MAP) systems are dendrimeric structures bearing multiple copies of identical or different peptide epitopes, and they have been demonstrated to show enhanced immunogenicity. Herein, we report the direct (divergent) and indirect (convergent) synthesis, using contemporary synthetic approaches, of a di-branched antigenic peptide (di-BAP) containing the immunodominant epitope MBP(83-99), which is implicated in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). The direct synthesis (di-BAP 1) was performed using microwave irradiation.
View Article and Find Full Text PDFTumor necrosis factor (TNF)- and TNF receptor I (TNFRI)-deficient mice are resistant to initiation and show delayed resolution of disease in paradigms of autoimmune disease, but the contribution of TNF/TNFRI signaling to T-cell activation and effector responses has not been determined. In this study, we investigated the role of TNFRI in T-cell receptor (TCR)-mediated T-cell activation in vitro and in vivo using CD3(+)-enriched primary T cells and mice deficient in TNFRI. Following TCR engagement, TNFRI knockout (KO) T cells showed significantly delayed proliferation, cell division, upregulation of interleukin 2 (IL-2) and IL-2 receptor alpha chain (CD25) mRNA and cell-surface expression of CD25 compared with wild-type (WT) cells.
View Article and Find Full Text PDFWe developed inducible and constitutive expression systems of Ha-RasV12 in HEK 293 cells to examine early oncogenic RasV12 signaling. Inducible expression of oncogenic Ras-triggered growth arrest, early senescence, and later apoptosis. Gene expression profile analysis revealed early Ras proliferation and cell cycle genes like c-fos, cyclin E, cdk2, cell-cell contact, and signaling like integrin a6, MEK5, and free radical signaling genes, like proline oxidase.
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