Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
NeuroRehabilitation ; 35(1): 97-104, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24990009

RESUMO

BACKGROUND: Physical capacity (PC) and quality of life (QoL) are both reduced in multiple sclerosis (MS). OBJECTIVE: Aim of our study was to investigate limitations in PC and QoL in response to the severity of MS. METHODS: The study involved 60 patients (PG) (Expanded Disability Status Scale EDSS 0-3:38, EDSS 3.5-6:22) and 48 healthy controls (CG). Endurance capacity was assessed as peak oxygen uptake (VO2peak) and ventilatory anaerobic threshold (VAT). Maximum force was measured in isokinetic testing. QoL was assessed using the SF-36-questionnaire and HALEMS. RESULTS: Patients with MS showed reduced VO2peak and QoL in comparison with CG. Patients with an EDSS >3 showed reduced VO2peak, and maximum force, however at the VAT there was no significant difference independent of the EDSS. The MS-specific QoL HALEMS and subscales 1, 4, 6, 8 and the physical sum score of the SF-36-questionnaire were evaluated to be better in patients with an EDSS ≤3. CONCLUSIONS: There are limitations within PC in patients with MS in comparison with a healthy CG; within the PG there are notes on a similar aerobic capacity but worsened anaerobic capacity in patients with an EDSS >3. This should be taken into account in future treatment strategies for training therapy.


Assuntos
Tolerância ao Exercício , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/psicologia , Qualidade de Vida/psicologia , Adulto , Avaliação da Deficiência , Ergometria/métodos , Tolerância ao Exercício/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/fisiopatologia , Inquéritos e Questionários
3.
Clin Exp Immunol ; 150(3): 509-17, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17903220

RESUMO

The C77G polymorphism in exon A of the human CD45 gene occurs with low frequency in healthy individuals. An enhanced frequency of C77G individuals has been reported in cohorts of patients suffering from multiple sclerosis, systemic sclerosis, autoimmune hepatitis, hepatitis C and human immunodeficiency virus (HIV)-1. C77G individuals overexpress CD45RA isoforms on activated/memory T cells. We have shown previously that aberrant expression of CD45RA isoforms enhances the intensity of T cell receptor (TCR) signalling. Here we report that the C77G polymorphism also influences the responsiveness of T cells to cytokines and alters their adhesion properties. When stimulated by interleukin (IL)-2, C77G T cells proliferated more strongly than wild-type controls and showed accelerated phosphorylation of Janus kinase (Jak1). Furthermore, C77G T cells exhibited a higher tendency to form homotypic aggregates in culture which could be enhanced significantly by antibody-mediated triggering of the variant CD45RA molecules. These data indicate that the changes in CD45 isoform combination resulting from C77G may not only affect TCR signalling but also cytokine-driven T cell responses and cellular adhesion. Altered immune responsiveness may enhance susceptibility of C77G carriers for certain diseases.


Assuntos
Citocinas/imunologia , Antígenos Comuns de Leucócito/genética , Esclerose Múltipla/imunologia , Linfócitos T/imunologia , Adulto , Adesão Celular/genética , Adesão Celular/imunologia , Diferenciação Celular/imunologia , Proliferação de Células , Células Cultivadas , Células Dendríticas/imunologia , Relação Dose-Resposta Imunológica , Heterozigoto , Humanos , Interleucina-2/imunologia , Antígenos Comuns de Leucócito/sangue , Pessoa de Meia-Idade , Monócitos/imunologia , Esclerose Múltipla/genética , Polimorfismo Genético , Isoformas de Proteínas/sangue , Isoformas de Proteínas/genética
4.
Eur J Neurol ; 13(12): 1359-63, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17116220

RESUMO

Intravenous immunoglobulin (IVIg) is an efficacious treatment for immune-mediated neuropathies like Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating neuropathy (CIDP), and multifocal motor neuropathy (MMN). In the pathogenesis of immune-mediated neuropathies chemokines and their receptors play a crucial role. Using flow cytometry we examined whether IVIg modulates chemokine expression repertoires of T cells and monocytes. The expression of inflammatory chemokine receptors CCR1, CCR2, CCR4, CCR5, CCR6 and CXCR3 was investigated on circulating T-cell subsets, and CCR1, CCR2 and CCR5 on circulating monocytes before and after IVIg treatment in patients with immune-mediated neuropathies (MMN, n = 7; GBS, n = 1; CIDP, n = 2). Furthermore, the homing potential of T cells was analyzed by the expression of CCR7, a chemokine receptor known to be utilized by mature T cells to recirculate into secondary lymphoid organs. In contrast to studies in chronic heart failure, no differences in expression patterns before and after IVIg treatment of any of the investigated chemokine receptors were found. Furthermore, the proportion of CD45RO-positive CD4+ or CD8+ T-cell subsets was not changed by IVIg treatment. Thus, we concluded that modulation of the expression of chemokine receptors on circulating leukocytes by IVIg is not a mode of action in immune-mediated neuropathies.


Assuntos
Doenças Autoimunes do Sistema Nervoso/tratamento farmacológico , Imunoglobulinas Intravenosas/uso terapêutico , Leucócitos Mononucleares/imunologia , Receptores de Quimiocinas/genética , Adulto , Idoso , Doenças Autoimunes do Sistema Nervoso/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/imunologia , Feminino , Citometria de Fluxo , Humanos , Fatores Imunológicos/uso terapêutico , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade
5.
Laryngorhinootologie ; 85(10): 755-9, 2006 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-17031763

RESUMO

A 53-year-old patient with myotonic dystrophy presented to our clinic with progressive bilateral hearing loss. The ENT status and particularly the otological examination were without pathological signs. Pure tone audiograms showed a bilateral moderate to severe sensorineural hearing loss. Routinely performed computed tomography of the temporal bones revealed the rare picture of exostosis of the internal auditory canals and the medial surface of the petrous bones. To our knowledge, this is the first report describing exostosis of the internal auditory canal in a patient with myotonic dystrophy, although at present it remains unclear in how far there is a causal connection between these two pathologies.


Assuntos
Meato Acústico Externo , Exostose , Perda Auditiva Neurossensorial/etiologia , Distrofia Miotônica/complicações , Osso Petroso , Audiometria de Tons Puros , Exostose/complicações , Exostose/diagnóstico por imagem , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Osso Petroso/diagnóstico por imagem , Osso Temporal/diagnóstico por imagem , Tomografia Computadorizada por Raios X
6.
Clin Exp Immunol ; 138(3): 499-506, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15544628

RESUMO

Interferon (IFN)-beta reduces the biological activity of multiple sclerosis (MS), a presumably T cell-mediated autoimmune disease of central nervous system (CNS) myelin. Co-stimulatory molecules are necessary for full T cell activation and differential expression of co-stimulatory molecules on antigen-presenting cells is thought to influence the type of effector T cell response (Th1/Th2). In this study we investigated the effects of IFN-beta on the expression of co-stimulatory molecules on lymphocytes and monocytes as a potential mechanism of action of IFN-beta in MS. Peripheral blood mononuclear cells (PBMCs) were stimulated with IFN-beta in vitro and expression of CD80, CD86, CD40 and HLA was examined by flow cytometry and reverse-transcription polymerase chain reaction. Whereas IFN-beta had no effect on the expression of these molecules on T and B lymphocytes there was a significant increase on monocytes. Correspondingly, the expression of mRNA increased after 6-18 h. This in vitro response was also observed in untreated MS patients and patients receiving treatment with IFN-beta. The increase of co-stimulatory molecules on monocytes was not mediated by interleukin (IL)-10. When IFN-beta-stimulated monocytes were used to stimulate autologous T cells an increased secretion of IL-13 was observed. In biopsies taken from IFN-beta-induced skin reactions after subcutaneous injection increased expression of CD80 mRNA was detected, indicating that IFN-beta also up-regulates this co-stimulatory molecule in vivo. These data provide the background for further studies of IFN-beta-induced changes of co-stimulatory molecules in MS patients.


Assuntos
Antígenos CD/análise , Antígeno B7-1/análise , Antígenos CD40/análise , Interferon beta/imunologia , Glicoproteínas de Membrana/análise , Monócitos/imunologia , Esclerose Múltipla/imunologia , Adulto , Antígenos CD/imunologia , Linfócitos B/imunologia , Antígeno B7-1/imunologia , Antígeno B7-2 , Antígenos CD40/imunologia , Células Cultivadas , Relação Dose-Resposta Imunológica , Feminino , Antígenos HLA-DR/análise , Antígenos HLA-DR/imunologia , Humanos , Interleucina-10/imunologia , Masculino , Glicoproteínas de Membrana/imunologia , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Linfócitos T , Regulação para Cima/imunologia
7.
Nervenarzt ; 74(10): 850-7, 2003 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-14551688

RESUMO

Accumulation and activation of mononuclear cells (lymphocytes and monocytes) in the CNS is one of the crucial steps in the pathogenesis of multiple sclerosis (MS). Chemokines and their receptors govern physiological and pathological leukocyte trafficking and may also be pertinent in hematogenous leukocyte infiltration of the CNS. Due to broad pharmacological interest in the chemokine system, peptide antagonists and small molecular antagonists are now available for clinical therapeutic trials. For the treatment of MS in particular, the chemokine receptors CCR1, CCR2, CCR5, and CXCR3 are possible targets in a chemokine-based therapeutic approach. In this review, we summarize current knowledge of the roles of chemokines and chemokine receptors in the pathogenesis of MS. Furthermore, options for possible therapeutic intervention through the chemokine system are outlined. Clinical studies in MS patients applying this knowledge are expected soon.


Assuntos
Quimiocinas/antagonistas & inibidores , Esclerose Múltipla/tratamento farmacológico , Receptores de Quimiocinas/antagonistas & inibidores , Animais , Quimiocinas/fisiologia , Humanos , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Esclerose Múltipla/imunologia , Receptores de Quimiocinas/fisiologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
8.
Clin Exp Immunol ; 133(3): 454-60, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12930374

RESUMO

Glatiramer acetate (GA) is effective in the treatment of Multiple Sclerosis (MS) presumably by the induction of an immunoregulatory T-cell response. We have previously shown that GA directly induces the Th2 cytokines IL-13 and IL-5 in T-cells in vitro. In the present study we compared the in vitro response to GA in healthy controls, untreated and GA-treated MS patients and tested whether the induction of IL-13 and IL-5 secretion is also detectable in the serum of 25 MS patients treated with GA. Patients were grouped into clinical responders and nonresponders in order to determine a possible correlation with the immunological response. As a result we found a significant increase of IL-13 in the serum of clinical GA-responders whereas IL-13 was not detectable in controls, untreated MS (P < 0.001) and nonresponders (P = 0.015). Similarly, GA-treatment increased serum levels of IL-5 (P = 0.001). The correlation of serum IL-5 and clinical response was also significant (P = 0.039), however, there was an overlap between the different groups. The selective induction of IL-13 and IL-5 but not IL-4 by GA treatment suggests that the specific biological functions of these cytokines might be important for the therapeutic mechanism of GA. Measurement of serum IL-13 and IL-5 levels is a simple and inexpensive tool for monitoring the response to GA in MS patients.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Interleucina-13/sangue , Interleucina-5/sangue , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/imunologia , Peptídeos/uso terapêutico , Adulto , Análise de Variância , Progressão da Doença , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Acetato de Glatiramer , Humanos , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
9.
J Neuroimmunol ; 119(1): 137-44, 2001 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-11525811

RESUMO

In order to define possible mechanisms of immunomodulation by glatiramer acetate (GA), we investigated the primary in vitro cytokine response of peripheral blood mononuclear cells (PBMCs) and T-cell subpopulations. In PBMCs from healthy subjects and untreated patients with multiple sclerosis (MS) GA-induced T-cell proliferation and mRNA expression/cytokine, secretion of IL-13 and IL-5 but not of IL-10, TGF-beta or IL-12, IL-4 was detected at the mRNA level only. IFN-gamma was induced in a few subjects at very low concentrations. The response to GA was driven by the CD4(+)/CD45RA(+) T-cell subpopulation and was mediated by T-cell receptor (TCR) engagement as determined by anti-TCR blocking antibodies. The findings are compatible with the hypothesis that GA functions as partial or weak TCR-agonist activating naive T cells to produce the Th2 cytokines IL-13 and IL-5.


Assuntos
Adjuvantes Imunológicos/farmacologia , Interleucina-13/sangue , Interleucina-5/sangue , Esclerose Múltipla Recidivante-Remitente/sangue , Peptídeos/farmacologia , Linfócitos T/metabolismo , Adulto , Divisão Celular/efeitos dos fármacos , Feminino , Acetato de Glatiramer , Humanos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Linfócitos T/citologia
11.
Neurology ; 54(1): 193-9, 2000 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-10636147

RESUMO

OBJECTIVE: To correlate Mx protein (Mx) levels in lysed blood leukocytes with the clinical response to interferon (IFN) beta-1b (IFNbeta-1b) in relapsing-remitting MS (RR-MS) patients for monitoring treatment. BACKGROUND: Intracellular Mx expression is exclusively induced by the type I IFNs (IFN-alpha, -beta, and -omega) or by viruses and is strongly increased under IFN treatment. Quantitative determination of Mx allows objective assessment of biological effects of IFN. METHODS: Mx protein levels were measured in blood leukocyte lysates from IFNbeta-1b-treated RR-MS patients by ELISA and correlated to clinical parameters, including relapse rate and clinical deterioration. RESULTS: In stable IFNbeta-1b-treated MS patients, Mx levels were significantly increased compared to patients with or without immunosuppressive treatment. In IFN-1b-treated MS patients during relapse, Mx levels were significantly lower than during stable phases of the disease. Mean values of Mx (MVMx) over time of treatment in patients with a reduction of relapse rate were significantly higher than in patients without response. CONCLUSION: Mx levels in lysed blood cells may represent a useful surrogate marker for IFNbeta-1b activity corresponding to the clinical response during treatment of MS.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Proteínas de Ligação ao GTP , Interferon beta/uso terapêutico , Leucócitos/metabolismo , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Proteínas/análise , Adjuvantes Imunológicos/efeitos adversos , Adulto , Anticorpos/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interferon beta-1a , Interferon beta-1b , Interferon beta/efeitos adversos , Interferon beta/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas de Resistência a Myxovirus
12.
J Leukoc Biol ; 66(6): 945-52, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10614776

RESUMO

Polymorphonuclear neutrophils (PMN) are part of the innate immune system and are first-line effector cells in acute inflammatory responses. On activation PMNs secrete cytokines and oxygen metabolites that might be involved in the regulation of the acquired immune response. We show here that peripheral blood PMNs constitutively express a B7-1-like molecule as detected by immunostaining with several B7-1 antibodies. Reverse transcriptase-polymerase chain reaction using three sets of primers spanning different regions of B7-1 indicate dissimilarities at the mRNA level. B7-1 mRNA is expressed in bone marrow cells and lipopolysaccharide (LPS)-stimulated but not in unstimulated PMNs. The B7-1-like molecule is localized to the cytoplasmic granules and translocated to the cell surface after stimulation with LPS or interleukin-12 in some donors. Binding of CTLA4-Ig suggests that the B7-1-like molecule can interact with functional B7 ligand and might be important in the immunobiology of PMNs.


Assuntos
Antígeno B7-1/biossíntese , Neutrófilos/metabolismo , Anticorpos Monoclonais , Antígenos CD/biossíntese , Antígenos CD/sangue , Antígenos CD/líquido cefalorraquidiano , Antígenos CD/genética , Antígenos de Superfície/biossíntese , Antígeno B7-1/sangue , Antígeno B7-1/líquido cefalorraquidiano , Antígeno B7-1/genética , Antígeno B7-2 , Células Cultivadas , Humanos , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/líquido cefalorraquidiano , Glicoproteínas de Membrana/genética , Meningites Bacterianas/sangue , Meningites Bacterianas/líquido cefalorraquidiano , Meningites Bacterianas/imunologia , Meningites Bacterianas/metabolismo , Ativação de Neutrófilo/imunologia , Neutrófilos/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/metabolismo , Coloração e Rotulagem/métodos
13.
Diagn Cytopathol ; 21(5): 313-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10527476

RESUMO

The examination of cerebrospinal fluid (CSF) continues to play an important role in the diagnosis of inflammatory diseases of the central nervous system (CNS). Immunocytochemistry and flow cytometry are the most commonly used methods for analysis of surface markers on CSF cells. We here compared these methods in the examination of CSF cells from a total of 68 patients with acute and chronic inflammatory CNS diseases. Expression of costimulatory molecules CD80 (B7-1) and CD86 (B7-2) as activation markers that are present at low density on the cell surface was analyzed in comparison to CD22 (B-cells) and CD4 (T-cell subset), that show high staining intensities. For CD22 and CD4, the results obtained with both methods were similar and reliable. Using flow cytometry, CD80 expression was detected in 6% of CSF cells in patients with chronic inflammatory CNS disease, as compared to 2% using immunocytochemistry, where the reliability of the data was found to be higher. We conclude that for examination of low-density surface markers on CSF cells, particularly with low cell counts, immunocytochemistry may be more reliable.


Assuntos
Antígenos de Superfície/biossíntese , Doenças do Sistema Nervoso Central/patologia , Líquido Cefalorraquidiano/citologia , Citometria de Fluxo , Imuno-Histoquímica , Antígenos CD/biossíntese , Doenças do Sistema Nervoso Central/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia
14.
J Neuroimmunol ; 96(1): 112-20, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10227430

RESUMO

The aberrant expression of B7 costimulatory molecules is involved in the pathogenesis of autoimmune diseases and overexpression of B7-1 was found in inflammatory multiple sclerosis (MS) lesions. We here report that costimulatory molecules B7-1 and B7-2 are expressed on cerebrospinal fluid (CSF) monocytes and B-lymphocytes from patients with MS, optic neuritis (ON) and other inflammatory central nervous system (CNS) diseases. In patients with ON but not MS, increased expression of B7-2 was detected as compared to non-inflammatory controls. The expression of B7-1 in MS and ON patients correlates with disease duration but not with relapses in patients with MS indicating a role in early disease but not as a reliable marker of disease activity at later stages of MS.


Assuntos
Antígenos CD/análise , Antígeno B7-1/análise , Líquido Cefalorraquidiano/citologia , Glicoproteínas de Membrana/análise , Esclerose Múltipla/imunologia , Neurite Óptica/imunologia , Antígenos CD/imunologia , Linfócitos B/química , Linfócitos B/imunologia , Antígeno B7-1/imunologia , Antígeno B7-2 , Líquido Cefalorraquidiano/imunologia , Humanos , Imuno-Histoquímica , Glicoproteínas de Membrana/imunologia , Microscopia Confocal , Monócitos/química , Monócitos/imunologia , Esclerose Múltipla/líquido cefalorraquidiano , Neurite Óptica/líquido cefalorraquidiano
15.
J Neuroimmunol ; 91(1-2): 1-9, 1998 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-9846813

RESUMO

The objective of this study was to determine whether autoreactive T cells in patients with multiple sclerosis (MS) are polarized and committed in their differentiation to a stable cytokine phenotype or whether the cytokine secretion can be altered. We examined the cytokines secreted by myelin basic protein (MBP) as compared to tetanus toxoid-reactive (TT) T cells in 12 patients with relapsing remitting MS (RR-MS), 9 patients with chronic progressive MS (CP-MS), and 14 normal individuals. A total of 5094 short term T cell lines to MBP and TT were generated in the presence of growth conditions promoting Th1 (IL-12/alpha-IL-4 mAb) or Th2 (IL-4/alpha-IL-12 mAb) cytokine secretion. Antigen-specific cytokine secretion from normals and MS patients could be shifted to a Th1 or Th2 type phenotype depending upon culture conditions, indicating that the phenotype of MBP reactive T cells can be altered even in longstanding chronic progressive MS. There were no significant differences in the cytokine patterns secreted by MBP reactive T cells in patients with MS as compared to normal individuals. However, CP-MS patients tended to have fewer MBP reactive T cells secreting IL-4 when cultured with IL-12/anti-IL-4 mAb and more IFN-gamma secreting MBP reactive T cells when cultured with IL-4/anti-IL-12 mAb as compared to both normal controls and RR-MS, suggesting that cells from these patients might be more polarized or that fewer undifferentiated MBP-reactive cells are present in these individuals. The most striking observation was that in contrast to the RR-MS patients and normal controls, almost none of the MBP reactive T cells secreting cytokines in CP-MS incorporated 3[H]thymidine. This may be due to chronic in vivo stimulation in the presence of IL-12, or because these T cells may have entered a terminally differentiated state. Nonetheless, the ability to alter the cytokine secretion of autoreactive T cell lines even in longstanding autoimmune disease indicates that cytokine therapy might have therapeutic benefits by switching the function of myelin reactive T cells such that they are non-pathogenic.


Assuntos
Citocinas/imunologia , Esclerose Múltipla/imunologia , Proteína Básica da Mielina/imunologia , Linfócitos T/imunologia , Anticorpos Monoclonais , Especificidade de Anticorpos , Divisão Celular/imunologia , Células Cultivadas , Humanos , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-12/imunologia , Interleucina-4/imunologia , Linfócitos T/citologia
16.
J Neuroimmunol ; 76(1-2): 132-8, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9184642

RESUMO

Human microglia constitute the primary residential antigen presenting cells (APCs) in the central nervous system (CNS) and have the capacity of activating myelin reactive T-cells. T-cell activation requires two signals: first is the interaction of the T-cell receptor with the MHC-antigen complex and, secondly, contact of the CD28/CTLA4 T-cell surface molecules with the B7 family of costimulatory molecules on the APCs. We have previously shown high expression of B7.1 in early multiple sclerosis (MS) plaques, suggesting that acute T-cell-mediated CNS inflammation may require local B7.1 upregulation. We have now examined the expression of B7.1 and B7.2 costimulatory molecules on resting ex-vivo human microglia isolated directly from biopsy specimens. We found constitutive expression of B7.2 but not B7.1 on resting microglia, suggesting that B7.2 expression may lead to downregulation of pro-inflammatory Th1 T-cell responses in the normal brain.


Assuntos
Autoimunidade , Antígeno B7-1/análise , Encéfalo/imunologia , Microglia/imunologia , Adolescente , Células Cultivadas , Pré-Escolar , Feminino , Humanos , Masculino
17.
Blood ; 89(9): 3303-14, 1997 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9129036

RESUMO

Human T-cell leukemia virus type I (HTLV-I)-infected T cells expanded in vitro by single-cell cloning provide a unique system for investigating virus-cell interactions in nonimmortalized T cells. By analysis of clones generated randomly from the blood of virus carriers, we confirm that CD4 T cells are the major reservoir of HTLV-I in vivo and show that most infected cells contain a single integrated provirus. Contrary to the situation in HTLV-I immortalized cell lines, the HTLV-I provirus was found to be transcriptionally silent in a high proportion of randomly generated T-cell clones and could not be reactivated by mitogenic stimulation. The spontaneous proliferation previously documented in HTLV-I-infected T-cell clones was not observed in silently infected cells, and therefore correlates directly with the expression of tax and other viral genes. The only cytokine mRNA found to be significantly elevated in the virus-producing clones was interleukin-6; however, receptor-blocking experiments argue against a role for IL-6 in the virus-induced cell proliferation. We observed a striking variation in the ability of individual HTLV-I-producing clones to immortalize fresh peripheral blood lymphocytes. This ability did not correlate with the levels of viral mRNA expression, gag p24 production, spontaneous proliferation, or tax-transactivation, possibly suggesting a role for host cell factors as determinants of viral infectivity or immortalization. Studies to elucidate the basis of this phenotypic heterogeneity should enhance our understanding of viral spread and pathogenesis.


Assuntos
Transformação Celular Viral , Citocinas/biossíntese , Vírus Linfotrópico T Tipo 1 Humano/genética , Southern Blotting , Divisão Celular , Linhagem Celular Transformada , Células Clonais , Primers do DNA , Produtos do Gene gag/biossíntese , Rearranjo Gênico do Linfócito T , Humanos , Fenótipo , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , Linfócitos T , Transcrição Gênica
18.
J Immunol ; 157(3): 1127-31, 1996 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8757617

RESUMO

A clear differentiation of Th1 and Th2 cytokine-secreting subsets in humans has not yet been defined. To further examine cytokine-directed differentiation of human T cell responses to both exogenous and autoantigens, we generated 346 short term T cell lines at limiting dilutions from six normal individuals to tetanus toxoid and myelin basic protein in the presence of IL-2 with or without the addition of IL-12 and anti-IL-4 mAb. T cell lines were examined for [3H]thymidine incorporation and cytokine secretion of IFN-gamma, IL-4, and IL-10. After culture in the presence of IL-12 and anti-IL-4 mAb, the predominant T cell response to Ag stimulation was simultaneous secretion of IL-10 and IFN-gamma. The concomitant secretion of IL-10 and IFN-gamma by T cells was confirmed by stimulating lines in the absence of APCs with plate-bound anti-CD3 mAb after two rounds of Ag-specific stimulation. Moreover, IL-12 enhanced IL-10 and IFN-gamma production in a myelin basic protein-reactive T cell clone, demonstrating that a differentiated T cell clone could be induced to secrete both cytokines. The addition of a neutralizing anti-IFN-gamma Ab to cultures with IL-12 and anti-IL-4 mAb during the generation of tetanus toxoid-reactive lines had no effect on the induction of IL-10 and IFN-gamma secretion, indicating that IL-12 and not IFN-gamma was responsible for the induction of this subset of T cells. Thus, in human T cells, IL-12 induces concomitant secretion of IL-10 and IFN-gamma.


Assuntos
Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-12/farmacologia , Células Th1/metabolismo , Células Th2/metabolismo , Adulto , Anticorpos Monoclonais , Humanos , Interleucina-4/metabolismo , Pessoa de Meia-Idade , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos
20.
J Exp Med ; 182(6): 1985-96, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-7500044

RESUMO

Resting autoreactive T cells are present in the circulation of normal individuals without pathologic consequences. In autoimmune animal models, stimulation of these self-reactive T cells in the presence of costimulatory molecules B7-1 results in T cell-mediated autoimmune disease, whereas B7-2 stimulation generates regulatory autoreactive T cells that abrogate disease severity. Thus, reactivation in the brain of myelin-autoreactive T cells by antigen with costimulatory molecules may be a critical event in the pathophysiology of multiple sclerosis (MS), a putative autoimmune disease of central nervous system (CNS) myelin. We investigated the expression of cytokines and costimulatory molecules in a panel of 41 histologically characterized CNS specimens from 15 MS and 10 control cases using semiquantitative reverse transcriptase-polymerase chain reaction and immunocytochemistry. In four cases, vascular CNS infarcts with inflammation were compared with MS plaques from the same brain. We observed increased expression of B7-1 and interleukin (IL) 12p40 in acute MS plaques, particularly from early disease cases but not in inflammatory infarcts. B7-1 staining was localized predominantly to the lymphocytes in perivenular inflammatory cuffs but not the parenchyma. In contrast, B7-2 was expressed predominantly on macrophages both in MS lesions of varied time duration and in inflammatory infarcts. These findings indicate that an early event in the initiation of MS involves upregulation of B7-1 and IL-12, resulting in conditions that maximally stimulate T cell activation and induction of T helper 1-type immune responses.


Assuntos
Antígenos CD/metabolismo , Antígeno B7-1/metabolismo , Encéfalo/imunologia , Interleucina-12/metabolismo , Glicoproteínas de Membrana/metabolismo , Esclerose Múltipla/imunologia , Adulto , Idoso , Antígeno B7-2 , Sequência de Bases , Encéfalo/patologia , Criança , Primers do DNA/química , Feminino , Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Imunofenotipagem , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Esclerose Múltipla/patologia , RNA Mensageiro/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA