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41.
Kathrin Pieper Marta Rizzi Matthaios Speletas Cristian R. Smulski Heiko Sic Helene Kraus Ulrich Salzer Gina J. Fiala Wolfgang W. Schamel Vassilios Lougaris Alessandro Plebani Lennart Hammarstrom Mike Recher Anastasios E. Germenis Bodo Grimbacher Klaus Warnatz Antonius G. Rolink Pascal Schneider Luigi D. Notarangelo Hermann Eibel 《The Journal of allergy and clinical immunology》2014
42.
Gijs Kooij Kathrin Kopplin Rosel Blasig Marchel Stuiver Nathalie Koning Gera Goverse Susanne M. A. van der Pol Bert van het Hof Maik Gollasch Joost A. R. Drexhage Arie Reijerkerk Iwan C. Meij Reina Mebius Thomas E. Willnow Dominik Müller Ingolf E. Blasig Helga E. de Vries 《Acta neuropathologica》2014,128(2):267-277
Multiple sclerosis (MS) is a chronic neuro-inflammatory disorder, which is marked by the invasion of the central nervous system by monocyte-derived macrophages and autoreactive T cells across the brain vasculature. Data from experimental animal models recently implied that the passage of leukocytes across the brain vasculature is preceded by their traversal across the blood–cerebrospinal fluid barrier (BCSFB) of the choroid plexus. The correlation between the presence of leukocytes in the CSF of patients suffering from MS and the number of inflammatory lesions as detected by magnetic resonance imaging suggests that inflammation at the choroid plexus contributes to the disease, although in a yet unknown fashion. We here provide first insights into the involvement of the choroid plexus in the onset and severity of the disease and in particular address the role of the tight junction protein claudin-3 (CLDN3) in this process. Detailed analysis of human post-mortem brain tissue revealed a selective loss of CLDN3 at the choroid plexus in MS patients compared to control tissues. Importantly, mice that lack CLDN3 have an impaired BCSFB and experience a more rapid onset and exacerbated clinical signs of experimental autoimmune encephalomyelitis, which coincides with enhanced levels of infiltrated leukocytes in their CSF. Together, this study highlights a profound role for the choroid plexus in the pathogenesis of multiple sclerosis, and implies that CLDN3 may be regarded as a crucial and novel determinant of BCSFB integrity. 相似文献
43.
Willingham SB Volkmer JP Gentles AJ Sahoo D Dalerba P Mitra SS Wang J Contreras-Trujillo H Martin R Cohen JD Lovelace P Scheeren FA Chao MP Weiskopf K Tang C Volkmer AK Naik TJ Storm TA Mosley AR Edris B Schmid SM Sun CK Chua MS Murillo O Rajendran P Cha AC Chin RK Kim D Adorno M Raveh T Tseng D Jaiswal S Enger PØ Steinberg GK Li G So SK Majeti R Harsh GR van de Rijn M Teng NN Sunwoo JB Alizadeh AA Clarke MF Weissman IL 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(17):6662-6667
CD47, a "don't eat me" signal for phagocytic cells, is expressed on the surface of all human solid tumor cells. Analysis of patient tumor and matched adjacent normal (nontumor) tissue revealed that CD47 is overexpressed on cancer cells. CD47 mRNA expression levels correlated with a decreased probability of survival for multiple types of cancer. CD47 is a ligand for SIRPα, a protein expressed on macrophages and dendritic cells. In vitro, blockade of CD47 signaling using targeted monoclonal antibodies enabled macrophage phagocytosis of tumor cells that were otherwise protected. Administration of anti-CD47 antibodies inhibited tumor growth in orthotopic immunodeficient mouse xenotransplantation models established with patient tumor cells and increased the survival of the mice over time. Anti-CD47 antibody therapy initiated on larger tumors inhibited tumor growth and prevented or treated metastasis, but initiation of the therapy on smaller tumors was potentially curative. The safety and efficacy of targeting CD47 was further tested and validated in immune competent hosts using an orthotopic mouse breast cancer model. These results suggest all human solid tumor cells require CD47 expression to suppress phagocytic innate immune surveillance and elimination. These data, taken together with similar findings with other human neoplasms, show that CD47 is a commonly expressed molecule on all cancers, its function to block phagocytosis is known, and blockade of its function leads to tumor cell phagocytosis and elimination. CD47 is therefore a validated target for cancer therapies. 相似文献
44.
L McHedlishvili V Mazurov KS Grassme K Goehler B Robl A Tazaki K Roensch A Duemmler EM Tanaka 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(34):E2258-E2266
We show that after tail amputation in Ambystoma mexicanum (Axolotl) the correct number and spacing of dorsal root ganglia are regenerated. By transplantation of spinal cord tissue and nonclonal neurospheres, we show that the central spinal cord represents a source of peripheral nervous system cells. Interestingly, melanophores migrate from preexisting precursors in the skin. Finally, we demonstrate that implantation of a clonally derived spinal cord neurosphere can result in reconstitution of all examined cell types in the regenerating central spinal cord, suggesting derivation of a cell with spinal cord stem cell properties. 相似文献
45.
B Sierra AB Pérez M Alvarez G García K Vogt E Aguirre K Schmolke HD Volk MG Guzmán 《The American journal of tropical medicine and hygiene》2012,87(3):538-547
Abstract. Secondary heterologous dengue infection is a risk factor for severe disease manifestations because of the immune-enhancement phenomenon. Succeeding clinical infections are seldom reported, and the clinical course of tertiary and quaternary dengue infections is not clear. Cuba represents a unique environment to study tertiary/quaternary dengue infections in a population with known clinical and serologic dengue markers and no dengue endemicity. We took advantage of this exceptional epidemiologic condition to study the effect of primary, secondary, tertiary, and quaternary dengue infection exposure on the expression of pro-inflammatory and regulatory cytokines, critical in dengue infection pathogenesis, by using a dengue infection ex vivo model. Whereas secondary exposure induced a high cytokine response, we found a significantly lower expression of tumor necrosis factor-α, interferon-γ, interleukin-10, and tumor growth factor-β after tertiary and quaternary infectious challenge. Significant differences in expression of the cytokines were seen between the dengue immune profiles, suggesting that the sequence in which the immune system encounters serotypes may be important in determining the nature of the immune response to subsequent infections. 相似文献
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48.
We have identified a population of normal mouse LN cells, termed LN lymphoid progenitor (LNLP), resembling common lymphoid progenitor (CLP) in the bone marrow. LNLPs lack lineage markers and express CD127, low levels of CD117 (c-Kit), and Sca-1, but lack fms-related tyrosine kinase 3. They efficiently differentiate in vitro into natural killer (NK) cells and T cells, but not mature B cells. LNLPs injected into nonirradiated lymphopenic mice that have no LN develop into mostly splenic T cells with low numbers of NK cells and B cells. When injected into irradiated mice, they generate NK cells and T cells, but not B cells, in the LN. By contrast, bone marrow CLPs develop into mostly B cells with very small numbers of T and NK cells in recipients' spleen and LN. LNLPs have NK and T-cell potentials, but little B-cell potential, and they can develop into NK cells within the LN of normal mice, but their contribution to the T-cell lineage is unknown. 相似文献
49.
Posterior alien hand syndrome is a new addition to a poorly understood group of movement disorders. Historically, anatomical lesions causing uncontrolled limb movement and a feeling of foreignness were found to be located in the corpus callosum or frontal lobe. Recent case reports, however, demonstrate the typical symptoms of alien hand syndrome with lesions located in the parietal/occipital lobes. Disturbance of normal function in these regions tends to produce less complex motor activity, such as hand levitation, along with a sensory component characterized by feeling of estrangement. We discuss a patient who presented with unusual symptoms following an outpatient procedure and was found to have posterior alien hand syndrome. 相似文献
50.
Maria Wostrack Nora Sandow Peter Vajkoczy Bawarjan Schatlo Philippe Bijlenga Karl Schaller Victoria Kehl Kathrin Harmening Florian Ringel Yu-Mi Ryang Benjamin Friedrich Michael Stoffel Bernhard Meyer 《Acta neurochirurgica》2013,155(4):579-586