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1.
Neurol Res Pract ; 3(1): 25, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33966627

RESUMO

BACKGROUND: All-trans retinoic acid (ATRA) is an acid derivative of vitamin A which is discussed as a promising candidate to ameliorate the disease course of multiple sclerosis (MS) by immunomodulation or even by promoting regeneration in progressive MS. Here we report a patient who significantly improved for MS related disability following administration of chemotherapy including ATRA for mitoxantrone-related acute promyelocytic leukemia and assess the effect of high-dose ATRA in three additional patients with progressive MS. METHODS: Patients with progressive MS who had failed previous therapies were treated with high-dose ATRA. Patients underwent clinical and routine laboratory monitoring. Additionally, PBMCs were analyzed by flow cytometry for lymphocyte subsets. RESULTS: ATRA was well tolerated and no pathological laboratory abnormalities were observed. After initial mild (not statistically significant) improvement of EDSS and mean MSFC z-score, ongoing disease progression was observed. One patient subacutely experienced severe cognitive and motor worsening. Cerebral MRI revealed persistent gadolinium-enhancing lesions. Flow cytometric alterations of peripheral blood naïve, central memory and effector memory CD4 and CD8 T cells, B lymphocytes, plasma cells, memory B cells, plasmablasts and natural killer (NK) cells did not reach statistical significance. CONCLUSIONS: Stand-alone therapy with ATRA did not ameliorate progressive MS in our limited cohort and we did not observe consistent alterations of T and B cell subsets. Intriguingly, application of ATRA may have caused marked disease exacerbation in one patient.

2.
Phys Rev Lett ; 123(11): 110402, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31573233

RESUMO

Quantum coherence is a fundamental feature of quantum mechanics and an underlying requirement for most quantum information tasks. In the resource theory of coherence, incoherent states are diagonal with respect to a fixed orthonormal basis; i.e., they can be seen as arising from a von Neumann measurement. Here, we introduce and study a generalization to a resource theory of coherence defined with respect to the most general quantum measurements, i.e., to arbitrary positive-operator-valued measures (POVMs). We establish POVM-based coherence measures and POVM-incoherent operations that coincide for the case of von Neumann measurements with their counterparts in standard coherence theory. We provide a semidefinite program that allows us to characterize interconversion properties of resource states and exemplify our framework by means of the qubit trine POVM, for which we also show analytical results.

3.
Mol Genet Metab ; 121(3): 206-215, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28583327

RESUMO

3-Hydroxy-3-methylglutaryl-coenzyme A lyase deficiency (HMGCLD) is a rare inborn error of ketone body synthesis and leucine degradation, caused by mutations in the HMGCL gene. In order to obtain a comprehensive view on this disease, we have collected clinical and biochemical data as well as information on HMGCL mutations of 37 patients (35 families) from metabolic centers in Belgium, Germany, The Netherlands, Switzerland, and Turkey. All patients were symptomatic at some stage with 94% presenting with an acute metabolic decompensation. In 50% of the patients, the disorder manifested neonatally, mostly within the first days of life. Only 8% of patients presented after one year of age. Six patients died prior to data collection. Long-term neurological complications were common. Half of the patients had a normal cognitive development while the remainder showed psychomotor deficits. We identified seven novel HMGCL mutations. In agreement with previous reports, no clear genotype-phenotype correlation could be found. This is the largest cohort of HMGCLD patients reported so far, demonstrating that HMGCLD is a potentially life-threatening disease with variable clinical outcome. Our findings suggest that the clinical course of HMGCLD cannot be predicted accurately from HMGCL genotype. The overall outcome in HMGCLD appears limited, thus rendering early diagnosis and strict avoidance of metabolic crises important.


Assuntos
Acetil-CoA C-Acetiltransferase/deficiência , Erros Inatos do Metabolismo dos Aminoácidos , Adolescente , Adulto , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/dietoterapia , Erros Inatos do Metabolismo dos Aminoácidos/fisiopatologia , Bélgica , Criança , Pré-Escolar , Ácidos Graxos/metabolismo , Feminino , Estudos de Associação Genética , Alemanha , Humanos , Lactente , Corpos Cetônicos/metabolismo , Leucina/metabolismo , Masculino , Mutação , Países Baixos , Oxo-Ácido-Liases/genética , Avaliação de Resultados da Assistência ao Paciente , Suíça , Turquia , Adulto Jovem
4.
Psychiatr Prax ; 44(2): 105-107, 2017 03.
Artigo em Alemão | MEDLINE | ID: mdl-27618172

RESUMO

Aim Emergency physicians are often confronted with psychiatric emergencies, but are not well trained for it and often feel unable to cope sufficiently with them. The aim of this investigation was to examine whether multisensoric training may improve learning effects in the training of emergency physicians with regard to psychiatric emergencies. Method Participation in a multi-modal, multi-media training program with video case histories and subsequent evaluation by questionnaire. Results 66 emergency physicians assessed their learning effects. 75 % or 73 % rated it as "rather high" or "very high". In particular, in comparison with classical training/self-study 89 % assessed the effects in learning as "rather high" or "very high" . Conclusion This training receives a high level of acceptance. Using videos, learning content may be provided more practice-related. Thus, emergency physicians are able to develop a greater understanding of psychiatric emergencies.


Assuntos
Educação de Pós-Graduação em Medicina , Serviços de Emergência Psiquiátrica , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Psiquiatria/educação , Treinamento por Simulação , Adulto , Currículo , Feminino , Alemanha , Humanos , Masculino , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Multimídia , Instruções Programadas como Assunto , Software , Inquéritos e Questionários , Gravação em Vídeo
5.
J Neuroinflammation ; 13(1): 289, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27832807

RESUMO

BACKGROUND: While exercise effects on the immune system have received increasing attention in recent years, it remains unclear to what extent gender and fluctuations in sex hormones during menstrual cycle influence immunological responses to exercise. METHODS: We investigated mRNA changes induced through exhaustive exercise (half-marathon; pre-exercise and post-exercise [30 min, 3 h, 24 h] on whole blood cultures ± lipopolysaccharide [LPS] [1 h]) with a specific focus on sex differences (men vs women in luteal phase) as an extension of our previous study. RESULTS: Inflammation related signaling pathways, TLRs, cytosolic DNA sensing and RIG-I like receptors were differentially activated between sexes in LPS-stimulated cultures. Genes differentially regulated between sexes included TNIP-1, TNIP-3, IL-6, HIVEP1, CXCL3, CCR3, IL-8, and CD69, revealing a bias towards less anti-inflammatory gene regulation in women compared to men. In addition, several genes relevant to brain function (KMO, DDIT4, VEGFA, IGF1R, IGF2R, and FGD4) showed differential activation between sexes. Some of these genes (e.g., KMO in women, DDIT4 in both sexes) potentially constitute neuroprotective mechanisms. CONCLUSIONS: These data reveal that the exercise-induced change in gene expression might be gender and menstrual cycle phase dependent.


Assuntos
Citocinas/metabolismo , Endotoxinas/farmacologia , Exercício Físico , Expressão Gênica/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adulto , Antropometria , Atletas , Células Cultivadas , Citocinas/genética , Feminino , Perfilação da Expressão Gênica , Hormônios , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Ciclo Menstrual/fisiologia , Fatores Sexuais , Fatores de Tempo
6.
Radiol Res Pract ; 2016: 2187275, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27006830

RESUMO

Flow diverters (FDs) are designed for the endovascular treatment of complex intracranial aneurysm configurations. From February 2009 to March 2013 28 patients (22 females, 6 males) were treated with FD; mean age was 57 years. Data, including aneurysm features, clinical presentation, history of previous bleeding, treatment, and follow-up results, are presented. Early postinterventional neurological deficits (transient: n = 3/enduring: n = 1) appeared in 4/28 patients (14%), and early improvement of neurological symptoms was observed in 7 patients with previous restriction of cranial nerve function. The overall occlusion rate was 20/26 (77%; 59% after 3 months). 77% achieved best results according to O'Kelly-Marotta score grade D with no contrast material filling (70% of those after 3 months). In 4/6 patients who did not achieve grade D, proximal and/or distal stent overlapping ≥5 mm was not guaranteed sufficiently. During follow-up we did not detect any aneurysm recurrence or haemorrhage. In-stent stenosis emerged as the most frequent complication (4/27; 15%) followed by 2 cases of vascular obliteration (AICA/VA). In conclusion endovascular reconstruction using a FD represents a modern and effective treatment in those aneurysms that are not suitable for conventional interventional or surgical treatment. The appearance of severe complications was rare.

7.
Neurol Neuroimmunol Neuroinflamm ; 2(6): e177, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26568972

RESUMO

OBJECTIVES: To assess alterations in the composition of peripheral immune cells in acute progressive multifocal leukoencephalopathy (PML). METHODS: Fresh blood samples from 5 patients with acute PML and 10 healthy controls were analyzed by flow cytometry for naive, central memory and effector memory CD4 and CD8 T cells, B lymphocytes, plasma cells, memory B cells, plasma blasts, and natural killer (NK) cells. The frequency of central memory CD4 T cells was determined longitudinally during the course of PML in 2 patients. RESULTS: The frequencies of naive, central memory and effector memory CD8 T cells, B cells, plasma cells, and NK cells were not altered in patients with PML. In contrast, the frequencies of naive CD4 T cells (p = 0.04) and central memory CD4 T cells (p < 0.00001) were reduced and the frequencies of effector memory CD4 T cells were increased (p = 0.01). Longitudinal analysis showed that this pattern was preserved in a patient with fatal PML outcome and restored in one patient who recovered from PML. CONCLUSIONS: These data indicate that PML is associated with reduced frequencies of peripheral central memory helper T cells but not with alterations in the frequencies of cytotoxic T cell populations, B lymphocytes, plasma cells, or NK cells.

8.
BMC Neurol ; 15: 108, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26152311

RESUMO

BACKGROUND: Progressive multifocal leukoencephalopathy is a severe demyelinating disease caused by the polyoma JC virus in patients with reduced immunocompetence. A few cases of progressive multifocal leukoencephalopathy have been reported in patients treated with fumaric acid esters. CASE PRESENTATION: A 53-year-old Caucasian woman reported to our clinic with a first focal epileptic seizure and mild cognitive impairment. Since 1.5 years, she was treated with fumaderm for her psoriasis. During that time, her lymphocyte counts ranged between 450 and 700/µl. Cerebral magnet resonance imaging showed multifocal subcortical T2 hyperintense lesions with partial gadolinium enhancement. She did not have antibodies against human immunodeficiency virus 1 and 2 and cerebrospinal fluid-polymerase chain reaction for viral infections including a sensitive JC-virus polymerase chain reaction were negative. The diagnosis of progressive multifocal leukoencephalopathy was established by histological analysis and detection of JC-virus desoxyribonucleic acid in brain biopsy specimens. Dimethyl fumarate was stopped and Mirtazapin and Mefloquin were initiated. Neurological examination and imaging remained stable. CONCLUSIONS: Progressive multifocal leukoencephalopathy can occur in patients with lymphocyte counts between 450 and 700/µl, produce only faint symptoms and is not excluded by negative JC-virus-polymerase chain reaction in cerebrospinal fluid. The incidence of progressive multifocal leukoencephalopathy may thus be underestimated and a more careful surveillance of patients would be necessary.


Assuntos
Fumarato de Dimetilo/administração & dosagem , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Encéfalo/patologia , Fumarato de Dimetilo/efeitos adversos , Feminino , Humanos , Vírus JC/isolamento & purificação , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
9.
Front Mol Neurosci ; 8: 21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26124703

RESUMO

In recent years, the ubiquitin-editing enzyme A20 has been shown to control a large set of molecular pathways involved in the regulation of protective as well as self-directed immune responses. Here, we assess the current and putative roles of A20 in inflammatory, vascular and degenerative diseases of the central nervous system and explore future directions of research.

10.
Eur J Radiol ; 83(12): 2190-2195, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25241049

RESUMO

BACKGROUND AND PURPOSE: Treatment of symptomatic intracranial atherosclerotic disease by angioplasty and stenting (PTAS) is limited by a high rate of periinterventional strokes. We performed a detailed analysis of these strokes at our center in order to identify strategies to reduce the risk of periinterventional complications. METHODS: Case records and imaging data of 80 patients with a symptomatic 70-99% stenosis of a major intracranial artery treated with PTAS between July 2007 and December 2013 were reviewed. All patients had a sufficient response to aspirin and clopidogrel. Periinterventional strokes were categorized as either ischemic (perforator territory, distal embolic or delayed stent thrombosis) or hemorrhagic (intraparenchymal, subarachnoid). RESULTS: Periinterventional complications occurred in 6/80 (7.5%) patients, consisting of 2 ischemic strokes (2.5%, both perforator territory), 3 hemorrhagic strokes (3.8%, 2 intraparenchymal due to reperfusion injury, 1 subarachnoid due to vessel rupture) and one death (1.3%) unrelated to stroke. All strokes occurred within 24h after PTAS. CONCLUSION: Our retrospective data analysis suggests that the risk of periinterventional stroke after PTAS of symptomatic intracranial atherosclerotic disease might be reduced by sufficient antiplatelet therapy and optimized management of patients with high risk for reperfusion injury or perforator strokes, including selection of a stenting device adapted to individual vessel morphology.


Assuntos
Angioplastia/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Arteriosclerose Intracraniana/terapia , Traumatismo por Reperfusão/prevenção & controle , Stents/efeitos adversos , Acidente Vascular Cerebral/prevenção & controle , Idoso , Aspirina/uso terapêutico , Clopidogrel , Complicações do Diabetes/complicações , Feminino , Humanos , Hiperlipidemias/complicações , Hipertensão/complicações , Arteriosclerose Intracraniana/complicações , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Traumatismo por Reperfusão/etiologia , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico
11.
J Immunol ; 193(3): 1035-46, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24973441

RESUMO

CD1d-restricted NKT cells can be divided into two groups: type I NKT cells use a semi-invariant TCR, whereas type II express a relatively diverse set of TCRs. A major subset of type II NKT cells recognizes myelin-derived sulfatides and is selectively enriched in the CNS tissue during experimental autoimmune encephalomyelitis (EAE). We have shown that activation of sulfatide-reactive type II NKT cells by sulfatide prevents induction of EAE. In this article, we have addressed the mechanism of regulation, as well as whether a single immunodominant form of synthetic sulfatide can treat ongoing chronic and relapsing EAE in SJL/J mice. We have shown that the activation of sulfatide-reactive type II NKT cells leads to a significant reduction in the frequency and effector function of myelin proteolipid proteins 139-151/I-A(s)-tetramer(+) cells in lymphoid and CNS tissues. In addition, type I NKT cells and dendritic cells (DCs) in the periphery, as well as CNS-resident microglia, are inactivated after sulfatide administration, and mice deficient in type I NKT cells are not protected from disease. Moreover, tolerized DCs from sulfatide-treated animals can adoptively transfer protection into naive mice. Treatment of SJL/J mice with a synthetic cis-tetracosenoyl sulfatide, but not α-galactosylceramide, reverses ongoing chronic and relapsing EAE. Our data highlight a novel immune-regulatory pathway involving NKT subset interactions leading to inactivation of type I NKT cells, DCs, and microglial cells in suppression of autoimmunity. Because CD1 molecules are nonpolymorphic, the sulfatide-mediated immune-regulatory pathway can be targeted for development of non-HLA-dependent therapeutic approaches to T cell-mediated autoimmune diseases.


Assuntos
Anergia Clonal/imunologia , Células Dendríticas/imunologia , Encefalomielite Autoimune Experimental/imunologia , Células T Matadoras Naturais/imunologia , Sulfoglicoesfingolipídeos/administração & dosagem , Transferência Adotiva/métodos , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Bovinos , Anergia Clonal/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/patologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Feminino , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/imunologia , Esclerose Múltipla Recidivante-Remitente/patologia , Proteína Proteolipídica de Mielina/administração & dosagem , Proteína Proteolipídica de Mielina/uso terapêutico , Células T Matadoras Naturais/efeitos dos fármacos , Células T Matadoras Naturais/patologia
12.
J Magn Reson Imaging ; 40(2): 334-40, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24470284

RESUMO

PURPOSE: Diffusion magnetic resonance imaging (MRI) is commonly used in acute stroke, but not considered diagnostic in ischemic optic neuropathy. This study evaluates the presence of diffusion restriction in patients with acute visual loss by analyzing diffusion-weighted images (DWI). MATERIALS AND METHODS: A retrospective study of all patients who clinically presented with acute visual loss and who underwent MRI with DWI between January 2011 and May 2012 were evaluated. Patients with suspected brainstem ischemia were used as a control group. Two neuroradiologists evaluated the DWI for the presence of diffusion restriction within the optic nerve. RESULTS: In all, 34 patients with acute visual deficit and 32 controls were evaluated. In all five cases of acute optic ischemia, diffusion restriction with reduced apparent diffusion coefficient was present. In 2/25 patients with clinically defined optic neuritis, a diffusion restriction was present. No diffusion restriction was seen in the control cases or in cases with other causes for an acute visual deficit. CONCLUSION: DWI can identify ischemic lesions of the optic nerve. As in acute multiple sclerosis lesions, optic neuritis can also present in rare circumstances with diffusion restriction and can therefore not be ruled out solely by DWI MRI.


Assuntos
Imagem de Tensor de Difusão/métodos , Nervo Óptico/patologia , Neuropatia Óptica Isquêmica/patologia , Transtornos da Visão/patologia , Substância Branca/patologia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuropatia Óptica Isquêmica/complicações , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Transtornos da Visão/etiologia
13.
J Neuroinflammation ; 10: 117, 2013 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-24053338

RESUMO

Neural stem/progenitor cells (NSPCs) have the ability to migrate into the central nervous system (CNS) to replace damaged cells. In inflammatory CNS disease, cytokine transduced neural stem cells may be used as vehicles to specifically reduce inflammation and promote cell replacement. In this study, we used NSPCs overexpressing IL-10, an immunomodulatory cytokine, in an animal model for CNS inflammation and multiple sclerosis (MS). Intravenous injection of IL-10 transduced neural stem/progenitor cells (NSPC(IL-10)) suppressed myelin oligodendrocyte glycoprotein aa 35-55 (MOG35-55)- induced experimental autoimmune encephalomyelitis (EAE) and, following intravenous injection, NSPC(IL-10) migrated to peripheral lymphoid organs and into the CNS. NSPC(IL-10 )suppressed antigen-specific proliferation and proinflammatory cytokine production of lymph node cells obtained from MOG35-55 peptide immunized mice. In this model, IL-10 producing NSPCs act via a peripheral immunosuppressive effect to attenuate EAE.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Interleucina-10/imunologia , Células-Tronco Neurais/imunologia , Células-Tronco Neurais/transplante , Transplante de Células-Tronco/métodos , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução Genética
15.
Brain Behav Immun ; 25(1): 120-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20837133

RESUMO

The role of regulatory T cell populations within the CNS in the regulation of CNS-autoimmunity is controversial. We show that during recovery from relapsing remitting experimental autoimmune encephalomyelitis, regulatory T cells accumulate within the CNS that express high levels of CD62L. These CD62L(high) Treg cells express increased amounts of CTLA-4, ICOS and TGF-ß and are more potent than CD62L(low) Treg cells in suppressing proliferation and inducing apoptosis in effector T cells. CD62L(high) Treg cells thus represent a population of Treg cells that display superior immunosuppressive properties and accumulate in the CNS during recovery from CNS-autoimmunity.


Assuntos
Sistema Nervoso Central/citologia , Sistema Nervoso Central/imunologia , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Terapia de Imunossupressão , Selectina L/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Animais , Anexina A5/metabolismo , Antígenos CD/biossíntese , Apoptose/efeitos dos fármacos , Antígeno CTLA-4 , Caspase 3/metabolismo , Feminino , Citometria de Fluxo , Imunização , Ligante Coestimulador de Linfócitos T Induzíveis , Camundongos , Proteína Proteolipídica de Mielina/imunologia , Fragmentos de Peptídeos/imunologia , Proteínas/genética , Proteínas/metabolismo , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/genética
16.
BMC Neurol ; 10: 76, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20809972

RESUMO

BACKGROUND: Allogeneic and autologous haematopoietic stem cell transplantation are established treatment options for haematological malignancies and may possibly be employed to treat a range of genetic and autoimmune diseases. CASE PRESENTATION: We report two patients who developed an acute myelitis within their thoracic spinal cord after allogeneic stem cell transplantation. Myelitis in these patients was not related to graft versus host disease or immune reconstitution and was responsive to intravenous methylprednisolone and cyclophosphamide. CONCLUSIONS: Myelitis is a possibly disabling consequence of haematopoietic stem cell transplantation.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Mielite/etiologia , Mielite/patologia , Idoso , Humanos , Leucemia/cirurgia , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Mielite/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Recidiva , Vértebras Torácicas
17.
Brain Behav Immun ; 23(6): 861-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19362139

RESUMO

Inflammation within the Central Nervous System (CNS) is largely controlled by the balance between CNS-specific effector and regulatory T lymphocytes. To suppress CNS-inflammation in an antigen-specific manner, CNS-specific effector and regulatory T cells thus have to be differentially regulated. We employed recombinant peptide/MHC class II tetramers to assess CNS-specific effector and regulatory T cells during the specific suppression of myelin proteolipid protein aa139-151 (PLP139-151)-induced experimental autoimmune encephalomyelitis (EAE) by intravenous injection of recombinant invariant chains (Ii) in which the CLIP region has been replaced by the PLP139-151 epitope (Ii-PLP139-151). Injection of Ii-PLP139-151 induced apoptosis in CNS-specific effector T cells. In contrast, the proportion of specific regulatory T cells was increased and these cells expressed larger amounts of molecules that mediate regulatory T cell function including transforming growth factor beta and the inducible costimulator (ICOS). Consequently, regulatory T cells from Ii-treated mice were more potent than regulatory T cells from control-treated animals in suppressing effector T cell proliferation. These data demonstrate that effector T cells and regulatory T cells directed against the same CNS-antigen can be differentially regulated in vivo to suppress CNS-autoimmunity. Recombinant Ii induce apoptosis in CNS-specific effector T cells and provoke qualitative changes in specific regulatory T cells that enhance their immunosuppressive properties.


Assuntos
Sistema Nervoso Central/citologia , Sistema Nervoso Central/imunologia , Tolerância Imunológica/fisiologia , Proteínas Recombinantes/farmacologia , Linfócitos T Reguladores/imunologia , Linfócitos T/imunologia , Transferência Adotiva , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Caspase 3/biossíntese , Caspase 3/genética , Encefalomielite Autoimune Experimental/imunologia , Citometria de Fluxo , Genes MHC da Classe II/imunologia , Linfonodos/citologia , Linfonodos/efeitos dos fármacos , Camundongos , Proteínas Recombinantes/química , Células Th2/imunologia
18.
Immunol Cell Biol ; 85(8): 575-81, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17592494

RESUMO

In addition to their immunostimulatory capacity, dendritic cells (DCs) play a crucial role in central and peripheral tolerance mechanisms. In the absence of an infection, immature DCs constantly take up, process and present self-antigens to specific T cells, which leads to the induction of T-cell anergy or deletion. In recent years, several additional mechanisms have been identified by which DCs constantly downregulate immune responses to maintain immunological tolerance. Among these are the complex interactions between several DC subtypes and different types of regulatory T cells. In this review, we summarize recent key findings and concepts in this field.


Assuntos
Autoimunidade/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica/imunologia , Linfócitos T Reguladores/imunologia , Animais , Antígeno B7-1/imunologia , Humanos , Timo/citologia , Timo/imunologia
19.
Prog Neuropsychopharmacol Biol Psychiatry ; 31(1): 301-3, 2007 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-17011097

RESUMO

Simple and complex auditory phantom-perceptions such as tinnitus and musical hallucinations occur predominantly in elderly subjects and are often associated with hearing impairment. Isolated verbal hallucinations without other psychotic features are rare. It has been shown that an intravenous (i.v.) injection of lidocaine can transiently suppress tinnitus. Here we present the case of a 74 year old left-handed women with severely distressing, continuous verbal auditory hallucinations without other psychotic features. I.v. injections of 100 mg lidocaine but not saline resulted in substantial transient suppressions of the hallucinations for several hours. Using [(15)O]H(2)O positron-emission tomography (PET) decreased regional cerebral blood flow associated with reduced perception of voices was found in the right angular and supramarginal gyrus, right inferior frontal gyrus, orbitofronal cortex and in major parts of the cingulate cortex. These data suggest to further investigate the clinical relevance of i.v. lidocaine in patients with therapy-resistant verbal hallucinations, support the notion of common pathophysiological mechanisms in different forms of auditory phantom-perception and demonstrate the feasibility of a new strategy for imaging studies on auditory hallucinations.


Assuntos
Anestésicos Locais/farmacologia , Circulação Cerebrovascular/efeitos dos fármacos , Alucinações/tratamento farmacológico , Alucinações/psicologia , Lidocaína/farmacologia , Idoso , Anestésicos Locais/administração & dosagem , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Feminino , Alucinações/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Injeções Intravenosas , Lidocaína/administração & dosagem , Tomografia por Emissão de Pósitrons , Escalas de Graduação Psiquiátrica
20.
J Immunol ; 177(7): 4384-90, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16982873

RESUMO

The prerequisites of peripheral activation of self-specific CD4(+) T cells that determine the development of autoimmunity are incompletely understood. SJL mice immunized with myelin proteolipid protein (PLP) 139-151 developed experimental autoimmune encephalomyelitis (EAE) when pertussis toxin (PT) was injected at the time of immunization but not when injected 6 days later, indicating that PT-induced alterations of the peripheral immune response lead to the development of autoimmunity. Further analysis using IA(s)/PLP(139-151) tetramers revealed that PT did not change effector T cell activation or regulatory T cell numbers but enhanced IFN-gamma production by self-specific CD4(+) T cells. In addition, PT promoted the generation of CD4(+)CD62L(low) effector T cells in vivo. Upon adoptive transfer, these cells were more potent than CD4(+)CD62L(high) cells in inducing autoimmunity in recipient mice. The generation of this population was paralleled by higher expression of the costimulatory molecules CD80, CD86, and B7-DC, but not B7-RP, PD-1, and B7-H1 on CD11c(+)CD4(+) dendritic cells whereas CD11c(+)CD8alpha(+) dendritic cells were not altered. Collectively, these data demonstrate the induction of autoimmunity by specific in vivo expansion of CD4(+)CD62L(low) cells and indicate that CD4(+)CD62L(low) effector T cells and CD11c(+)CD4(+) dendritic cells may be attractive targets for immune interventions to treat autoimmune diseases.


Assuntos
Autoimunidade , Linfócitos T CD4-Positivos/imunologia , Encefalomielite Autoimune Experimental/imunologia , Tolerância Imunológica , Selectina L/metabolismo , Adjuvantes Imunológicos , Transferência Adotiva , Animais , Antígeno B7-1/imunologia , Antígeno B7-1/metabolismo , Antígeno B7-2/imunologia , Antígeno B7-2/metabolismo , Antígeno CD11c/imunologia , Antígeno CD11c/metabolismo , Linfócitos T CD4-Positivos/citologia , Diferenciação Celular/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Citometria de Fluxo , Selectina L/imunologia , Ativação Linfocitária/imunologia , Camundongos , Proteína Proteolipídica de Mielina/imunologia , Fragmentos de Peptídeos/imunologia , Toxina Pertussis/imunologia , Proteína 2 Ligante de Morte Celular Programada 1
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