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1.
Clin Gastroenterol Hepatol ; 19(10): 2207-2209.e3, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33068786

RESUMO

The safety and efficacy of tofacitinib in Crohn's disease (CD) has been studied in 2 phase II trials in patients with moderate-to-severe CD with no new safety signals observed, but no significant difference from placebo in the primary efficacy endpoint of clinical response.1-3 However, post hoc analyses and smaller studies have observed clinical and biologic response to tofacitinib in patients with CD.2,4,5 There is a paucity of real-world effectiveness and safety data for tofacitinib in non-Food and Drug Administration label usage in patients with CD and patients with inflammatory bowel disease-unclassified (IBD-U).


Assuntos
Doença de Crohn , Doenças Inflamatórias Intestinais , Doença de Crohn/tratamento farmacológico , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Piperidinas , Pirimidinas/efeitos adversos , Pirróis/efeitos adversos
2.
Clin Gastroenterol Hepatol ; 19(8): 1592-1601.e3, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32629130

RESUMO

BACKGROUND & AIMS: Adverse events (AEs) including reactivation of herpes zoster (HZ) and venous thromboembolism (VTE) have been reported from clinical trials of tofacitinib in ulcerative colitis (UC). We investigated the incidence rates of AEs in a real-world study of UC patients given tofacitinib. METHODS: We collected data from 260 patients with UC in the Tofacitinib Real-world Outcomes in Patients with ulceratIve colitis and Crohn's disease consortium study, performed at 6 medical centers in the United States. Patients were followed up for a median of 6 months (interquartile range, 2.7-11.5 mo). AEs were captured using a standardized data collection instrument before study initiation and at weeks 8, 16, 26, 39, and 52. Serious AEs were defined as life-threatening or resulting in a hospitalization, disability, or discontinuation of therapy. Logistic regression was performed to examine risk factors for AEs. RESULTS: AEs occurred in 41 patients (15.7%); most were infections (N = 13; 5.0%). The incidence rate of any AE was 27.2 (95% CI, 24.4-30.7 per 100 patient-years of follow-up evaluation). Fifteen were serious AEs (36.6% of AEs), and tofacitinib was discontinued for 12 patients (4.6% of cohort). The incidence rates of serious AEs was 10.0 (95% CI, 8.9-11.2 per 100 patient-years of follow-up evaluation). Five patients developed HZ infection and 2 developed VTE (all receiving 10 mg tofacitinib, twice per day). CONCLUSIONS: Real-world safety signals for tofacitinib are similar to those for clinical trials, with AEs reported from almost 16% of patients. HZ infection and VTE occurred in patients receiving 10 mg tofacitinib twice per day. These results support dose de-escalation after induction therapy, to reduce the risk of AEs.


Assuntos
Colite Ulcerativa , Colite Ulcerativa/tratamento farmacológico , Humanos , Piperidinas/efeitos adversos , Pirimidinas/efeitos adversos , Pirróis/efeitos adversos
5.
Cell Host Microbe ; 24(3): 353-363.e5, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30122655

RESUMO

Colonic wound repair is an orchestrated process, beginning with barrier re-establishment and followed by wound channel formation and crypt regeneration. Elevated levels of prostaglandin E2 (PGE2) promote barrier re-establishment; however, we found that persistently elevated PGE2 hinders subsequent repair phases. The bacterial metabolite deoxycholate (DCA) promotes transition through repair phases via PGE2 regulation. During barrier re-establishment, DCA levels are locally diminished in the wound, allowing enhanced PGE2 production and barrier re-establishment. However, during transition to the wound channel formation phase, DCA levels increase to inhibit PGE2 production and promote crypt regeneration. Altering DCA levels via antibiotic treatment enhances PGE2 levels but impairs wound repair, which is rescued with DCA treatment. DCA acts via its receptor, farnesoid X receptor, to inhibit the enzyme cPLA2 required for PGE2 synthesis. Thus, colonic wound repair requires temporally regulated signals from microbial metabolites to coordinate host-associated signaling cascades. VIDEO ABSTRACT.


Assuntos
Bactérias/metabolismo , Colo/lesões , Colo/fisiologia , Ácido Desoxicólico/metabolismo , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/lesões , Cicatrização , Animais , Biópsia , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Hidroxiprostaglandina Desidrogenases/farmacologia , Mucosa Intestinal/fisiologia , Camundongos , Camundongos Knockout , Nitrobenzenos/farmacologia , Cultura Primária de Células , Sulfonamidas/farmacologia , Vancomicina/farmacologia
6.
Science ; 357(6350): 498-502, 2017 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-28774928

RESUMO

The microbiota is known to modulate the host response to influenza infection through as-yet-unclear mechanisms. We hypothesized that components of the microbiota exert effects through type I interferon (IFN), a hypothesis supported by analysis of influenza in a gain-of-function genetic mouse model. Here we show that a microbially associated metabolite, desaminotyrosine (DAT), protects from influenza through augmentation of type I IFN signaling and diminution of lung immunopathology. A specific human-associated gut microbe, Clostridium orbiscindens, produced DAT and rescued antibiotic-treated influenza-infected mice. DAT protected the host by priming the amplification loop of type I IFN signaling. These findings show that specific components of the enteric microbiota have distal effects on responses to lethal infections through modulation of type I IFN.


Assuntos
Clostridium perfringens/metabolismo , Microbioma Gastrointestinal/imunologia , Interferon Tipo I/imunologia , Infecções por Orthomyxoviridae/imunologia , Fenilpropionatos/imunologia , Animais , Linhagem Celular , Proteínas de Ligação ao GTP/genética , Interações Hospedeiro-Patógeno/imunologia , Pulmão/imunologia , Camundongos , Camundongos Knockout , Fenilpropionatos/metabolismo , Transdução de Sinais
7.
J Gastrointestin Liver Dis ; 26(2): 183-187, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28617889

RESUMO

BACKGROUND: Non-Langerhans histiocytosis is a group of inflammatory lymphoproliferative disorders originating from non-clonal expansion of hematopoietic stem cells into cytokine-secreting dendritic cells or macrophages. Erdheim-Chester Disease (ECD) is a rare type of non-Langerhans cell histiocytosis characterized by tissue inflammation and injury caused by macrophage infiltration and histologic findings of foamy histiocytes. Often ECD involves the skeleton, retroperitoneum and the orbits. This is the first report documenting ECD manifesting as segmental colitis and causing cytokine-release syndrome. CASE PRESENTATION: A 68-year old woman presented with persistent fever without infectious etiology and hematochezia. Endoscopy showed segmental colitis and pathology revealed infiltration of large foamy histiocytes CD3-/CD20-/CD68+/CD163+/S100- consistent with ECD. The patient was empirically treated with steroids but continued to have fever and developed progressive distributive shock. CONCLUSION: This case report describes the differential diagnosis of infectious and immune-mediated inflammatory and rheumatologic segmental colitis. Non-Langerhans histiocytosis and ECD are rare causes of gastrointestinal inflammation. Prompt diagnosis is imperative for the appropriate treatment to prevent hemodynamic compromise due to distributive shock or gastrointestinal bleeding. Importantly, gastrointestinal ECD might exhibit poor response to steroid treatment and other potential treatments including chemotherapy, and biologic treatments targeting IL-1 and TNF-alpha signalling should be considered.


Assuntos
Colite/etiologia , Colo/imunologia , Citocinas/imunologia , Doença de Erdheim-Chester/complicações , Histiócitos/imunologia , Idoso , Biópsia , Colite/diagnóstico , Colite/tratamento farmacológico , Colite/imunologia , Colo/efeitos dos fármacos , Colo/patologia , Colonografia Tomográfica Computadorizada , Colonoscopia , Doença de Erdheim-Chester/diagnóstico , Doença de Erdheim-Chester/tratamento farmacológico , Doença de Erdheim-Chester/imunologia , Feminino , Histiócitos/efeitos dos fármacos , Histiócitos/patologia , Humanos , Esteroides/uso terapêutico , Resultado do Tratamento
8.
Clin Exp Gastroenterol ; 9: 125-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27274301

RESUMO

Ulcerative colitis (UC) is an immune-mediated disease of the colon that is characterized by diffuse and continuous inflammation contiguous from the rectum. Half of UC patients have inflammation limited to the distal colon (proctitis or proctosigmoiditis) that primarily causes symptoms of bloody diarrhea and urgency. Mild-to-moderate distal UC can be effectively treated with topical formulations (rectal suppositories, enemas, or foam) of mesalamine or steroids to reduce mucosal inflammation and alleviate symptoms. Enemas or foam formulations adequately reach up to the splenic flexure, have a minimal side-effect profile, and induce remission alone or in combination with systemic immunosuppressive therapy. Herein, we compare the efficacy, cost, patient tolerance, and side-effect profiles of steroid and mesalamine rectal formulations in distal UC. Patients with distal mild-to-moderate UC have a remission rate of approximately 75% (NNT =2) after treatment for 6 weeks with mesalamine enemas. Rectal budesonide foam induces remission in 41.2% of patients with mild-to-moderate active distal UC compared to 24% of patient treated with placebo (NNT =5). However, rectal budesonide has better patient tolerance profile compared to enema formulations. Despite its favorable efficacy, safety, and cost profiles, patients and physicians significantly underuse topical treatments for treating distal colitis. This necessitates improved patient education and physician familiarity regarding the indications, effectiveness, and potential financial and tolerability barriers in using rectal formulations.

10.
Glia ; 63(10): 1753-71, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25919645

RESUMO

We have previously described reduced myelination and corresponding myelin basic protein (MBP) expression in the central nervous system of Src homology 2 domain-containing protein tyrosine phosphatase 1 (SHP-1) deficient motheaten (me/me) mice compared with normal littermate controls. Deficiency in myelin and MBP expression in both brains and spinal cords of motheaten mice correlated with reduced MBP mRNA expression levels in vivo and in purified oligodendrocytes in vitro. Therefore, SHP-1 activity seems to be a critical regulator of oligodendrocyte gene expression and function. Consistent with this role, this study demonstrates that oligodendrocytes of motheaten mice and SHP-1-depleted N20.1 cells produce higher levels of reactive oxygen species (ROS) and exhibit corresponding markers of increased oxidative stress. In agreement with these findings, we demonstrate that increased production of ROS coincides with ROS-induced signaling pathways known to affect myelin gene expression in oligodendrocytes. Antioxidant treatment of SHP-1-deficient oligodendrocytes reversed the pathological changes in these cells, with increased myelin protein gene expression and decreased expression of nuclear factor (erythroid-2)-related factor 2 (Nrf2) responsive gene, heme oxygenase-1 (HO-1). Furthermore, we demonstrate that SHP-1 is expressed in human white matter oligodendrocytes, and there is a subset of multiple sclerosis subjects that demonstrate a deficiency of SHP-1 in normal-appearing white matter. These studies reveal critical pathways controlled by SHP-1 in oligodendrocytes that relate to susceptibility of SHP-1-deficient mice to both developmental defects in myelination and to inflammatory demyelinating diseases.


Assuntos
Sistema Nervoso Central/patologia , Regulação da Expressão Gênica/genética , Esclerose Múltipla/patologia , Oligodendroglia/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Animais Recém-Nascidos , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Camundongos , Camundongos Transgênicos , Esclerose Múltipla/genética , Proteínas da Mielina/genética , Proteínas da Mielina/metabolismo , NF-kappa B/metabolismo , Carbonilação Proteica/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética
11.
Biol Chem ; 395(9): 1063-73, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25153387

RESUMO

Recent studies provide a functional link between kallikrein 6 (Klk6) and the development and progression of disease in patients with multiple sclerosis (MS) and in its murine models. To evaluate the involvement of additional kallikrein family members, we compared Klk6 expression with four other kallikreins (Klk1, Klk7, Klk8, and Klk10) in the brain and spinal cord of mice infected with Theiler's murine encephalomyelitis virus, an experimental model of progressive MS. The robust upregulation of Klk6 and Klk8 in the brain during the acute phase of viral encephalitis and in the spinal cord during disease development and progression points to their participation in inflammation, demyelination, and progressive axon degeneration. More limited changes in Klk1, Klk7, and Klk10 were also observed. In addition, Klk1, Klk6, and Klk10 were dynamically regulated in T cells in vitro as a recall response to viral antigen and in activated monocytes, pointing to their activities in the development of adaptive and innate immune function. Together, these results point to overlapping and unique roles for multiple kallikreins in the development and progression of virus-mediated central nervous system inflammatory demyelinating disease, including activities in the development of the adaptive and innate immune response, in demyelination, and in progressive axon degeneration.


Assuntos
Imunidade Adaptativa/genética , Perfilação da Expressão Gênica , Imunidade Inata/genética , Calicreínas/genética , Esclerose Múltipla/imunologia , Esclerose Múltipla/virologia , Theilovirus/fisiologia , Animais , Encéfalo/patologia , Proteínas do Capsídeo/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Calicreínas/metabolismo , Ativação Linfocitária/genética , Camundongos , Monócitos/metabolismo , Esclerose Múltipla/genética , Medula Espinal/patologia , Baço/patologia , Linfócitos T/metabolismo , Fatores de Tempo , Transcrição Gênica
12.
Exp Mol Pathol ; 96(3): 393-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24768588

RESUMO

Sarcoidosis is an immune-mediated multisystem disease characterized by the formation of non-caseating granulomas. The pathogenesis of sarcoidosis is unclear, with proposed infectious or environmental antigens triggering an aberrant immune response in susceptible hosts. Multiple pro-inflammatory signaling pathways have been implicated in mediating macrophage activation and granuloma formation in sarcoidosis, including IFN-γ/STAT-1, IL-6/STAT-3, and NF-κB. It is difficult to distinguish sarcoidosis from other granulomatous diseases or assess disease severity and treatment response with histopathology alone. Therefore, development of improved diagnostic tools is imperative. Herein, we describe an efficient and reliable technique to classify granulomatous disease through selected gene expression and identify novel genes and cytokine pathways contributing to the pathogenesis of sarcoidosis. We quantified the expression of twenty selected mRNAs extracted from formalin-fixed paraffin embedded (FFPE) tissue (n = 38) of normal lung, suture granulomas, sarcoid granulomas, and fungal granulomas. Utilizing quantitative real-time RT-PCR we analyzed the expression of several genes, including IL-6, COX-2, MCP-1, IFN-γ, T-bet, IRF-1, Nox2, IL-33, and eotaxin-1 and revealed differential regulation between suture, sarcoidosis, and fungal granulomas. This is the first study demonstrating that quantification of target gene expression in FFPE tissue biopsies is a potentially effective diagnostic and research tool in sarcoidosis.


Assuntos
Marcadores Genéticos , Granuloma/genética , Sarcoidose/diagnóstico , Sarcoidose/genética , Transcriptoma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiocina CCL11/genética , Quimiocina CCL11/metabolismo , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Criança , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Feminino , Expressão Gênica , Granuloma/imunologia , Granuloma/patologia , Humanos , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-33 , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , NADPH Oxidase 2 , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Sarcoidose/imunologia , Sarcoidose/patologia , Manejo de Espécimes , Regulação para Cima , Adulto Jovem
13.
Inflamm Bowel Dis ; 18(12): 2342-56, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22467146

RESUMO

BACKGROUND: Cytokine signaling pathways play a central role in the pathogenesis of inflammatory bowel disease (IBD). Ulcerative colitis (UC) and Crohn's disease (CD) have unique as well as overlapping phenotypes, susceptibility genes, and gene expression profiles. This study aimed to delineate patterns within cytokine signaling pathways in colonic mucosa of UC and CD patients, explore molecular diagnostic markers, and identify novel immune mediators in IBD pathogenesis. METHODS: We quantified 70 selected immune genes that are important in IBD signaling from formalin-fixed, paraffin-embedded (FFPE) colon biopsy samples from normal control subjects and UC and CD patients having either severe colitis or quiescent disease (n = 98 subjects). We utilized and validated a new modified real-time reverse-transcription polymerase chain reaction (RT-PCR) technique for gene quantification. RESULTS: Expression levels of signaling molecules including IL-6/10/12/13/17/23/33, STAT1/3/6, T-bet, GATA3, Foxp3, SOCS1/3, and downstream inflammatory mediators such as chemokines CCL-2/11/17/20, oxidative stress inducers, proteases, and mucosal genes were differentially regulated between UC and CD and between active and quiescent disease. We also document the possible role of novel genes in IBD, including SHP-1, IRF-1,TARC, Eotaxin, NOX2, arginase I, and ADAM 8. CONCLUSIONS: This comprehensive approach to quantifying gene expression provides insights into the pathogenesis of IBD by elucidating distinct immune signaling networks in CD and UC. Furthermore, this is the first study demonstrating that gene expression profiling in FFPE colon biopsies might be a practical and effective tool in the diagnosis and prognosis of IBD and may help identify molecular markers that can predict and monitor response to individualized therapeutic treatments.


Assuntos
Colite Ulcerativa/etiologia , Doença de Crohn/etiologia , Citocinas/fisiologia , Transdução de Sinais/imunologia , Adulto , Biomarcadores/metabolismo , Quimiocinas/fisiologia , Colite Ulcerativa/imunologia , Colo/imunologia , Doença de Crohn/imunologia , Feminino , Genes/imunologia , Humanos , Mucosa Intestinal/imunologia , Masculino , Estresse Oxidativo/imunologia , Estresse Oxidativo/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/fisiologia
14.
Clin Immunol ; 142(3): 308-19, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22189043

RESUMO

Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system (CNS). Here we document for the first time that the cytokine IL-33 is upregulated in both the periphery and the CNS of MS patients. Plasma IL-33 was elevated in MS patients compared to normal subjects and a three-month treatment of MS patients with interferon ß-1a resulted in a significant decrease of IL-33 levels. Similarly, stimulated cultured lymphocytes and macrophages from MS patients had elevated IL-33 levels compared to normal subjects. In parallel, the transcription factor NF-κB that mediates IL-33 transcription was also elevated in leukocytes of MS patients. IL-33 was elevated in normal-appearing white matter and plaque areas from MS brains and astrocytes were identified as an important source of IL-33 expression in the CNS. In summary, IL-33 levels are elevated in the periphery and CNS of MS patients, implicating IL-33 in the pathogenesis of MS.


Assuntos
Sistema Nervoso Central/imunologia , Interleucinas/imunologia , Linfócitos/imunologia , Esclerose Múltipla/imunologia , Adulto , Células Cultivadas , Feminino , Humanos , Interleucina-33 , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , NF-kappa B/imunologia , Regulação para Cima
15.
J Neurol Sci ; 307(1-2): 41-5, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21658727

RESUMO

Interferon-ß (IFN-ß) is a current effective treatment for multiple sclerosis (MS) and exerts its therapeutic effects by down-modulating the systemic immune response and cytokine signaling. In clinical practice there are several formulations of interferon including a low dose of IFN-ß 1a formulation of 30 µg IM once weekly (Avonex) and a high dose formulation of 44 µg SC three times weekly (Rebif). Recent studies suggest that Rebif is more efficacious compared to Avonex in preventing relapses and decreasing MRI activity in relapsing remitting MS (RRMS) patients. This study examines whether there are quantitative gene expression changes in interferon-treated RRMS patients that can explain the difference in efficacy and side effects between Rebif and Avonex. Herein, RRMS patients were treated for three months with IFN-ß 1a and the levels of plasma cytokines and gene expression in peripheral blood mononuclear cells were examined. Thirty-two normal subjects were compared to thirty-two RRMS patients, of which ten were treated with Rebif and ten with Avonex. Rebif and Avonex both significantly and equally suppressed plasma TNF-α and IL-6 levels. Rebif suppressed IL-13 significantly more than Avonex. Rebif also significantly suppressed the levels of the chemokines CCL17 and RANTES, the protease ADAM8, and COX-2 at a higher degree compared to Avonex. The STAT1-inducible genes IP-10 and caspase 1 were significantly increased with Rebif compared to Avonex. In conclusion, the higher dosed, more frequently administered IFN-ß 1a Rebif when compared to IFN-ß 1a Avonex has more potent immunomodulatory effects. These quantitative results might relate to efficacy and side-effect profile of the two IFN-ß 1a formulations and provide prospective practical clinical tools to monitor treatment and adjust dosage.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/fisiologia , Interferon beta/administração & dosagem , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adjuvantes Imunológicos/administração & dosagem , Adulto , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Monitoramento de Medicamentos/métodos , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Interferon beta-1a , Interferon beta/uso terapêutico , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/genética , Esclerose Múltipla Recidivante-Remitente/imunologia , Prevenção Secundária , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/imunologia
16.
Viral Immunol ; 22(6): 371-87, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19951174

RESUMO

SHP-1 is a protein tyrosine phosphatase that negatively regulates cytokine signaling and inflammatory gene expression. Mice genetically lacking SHP-1 (me/me) display severe inflammatory demyelinating disease following intracranial inoculation with the BeAn strain of Theiler's murine encephalomyelitis virus (TMEV) compared to infected wild-type mice. Furthermore, SHP-1-deficient mice show a profound and predominant infiltration of blood-derived macrophages into the CNS following intracerebral injection of TMEV, and these macrophages are concentrated in areas of demyelination in brain and spinal cord. In the present study we investigated the role of SHP-1 in controlling CNS inflammatory demyelination following a peripheral instead of an intracerebral inoculation of TMEV. Surprisingly, we found that while wild-type mice were entirely refractory to intraperitoneal (IP) infection by TMEV, in agreement with previous studies, all SHP-1-deficient mice displayed profound macrophage neuroinvasion and macrophage-mediated inflammatory demyelination. Moreover, SHP-1 deficiency led to increased expression of inflammatory molecules in macrophages, serum, and CNS following IP infection with TMEV. Importantly, pharmacological depletion of peripheral macrophages significantly decreased both paralysis and CNS viral loads in SHP-1-deficient mice. In addition, peripheral MCP-1 neutralization attenuated disease severity, decreased macrophage infiltration into the CNS, and decreased monocyte numbers in the blood of SHP-1-deficient mice, implicating MCP-1 as an important mediator of monocyte migration between multiple tissues. These results demonstrate that peripheral TMEV infection results in a unique evolution of macrophage-mediated demyelination in SHP-1-deficient mice, implicating SHP-1 in the control of neuroinvasion of inflammatory macrophages and neurotropic viruses into the CNS.


Assuntos
Infecções por Cardiovirus/complicações , Sistema Nervoso Central/patologia , Doenças Desmielinizantes/etiologia , Macrófagos/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/fisiologia , Theilovirus/patogenicidade , Animais , Infecções por Cardiovirus/imunologia , Infecções por Cardiovirus/patologia , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/virologia , Quimiocina CCL2/fisiologia , Quimiocinas/biossíntese , Quimiocinas/genética , Quimiotaxia de Leucócito , Ácido Clodrônico/farmacologia , Citocinas/biossíntese , Citocinas/genética , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/virologia , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Injeções Intraperitoneais , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C3H , Camundongos Knockout , Camundongos Mutantes , Paralisia/etiologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/deficiência , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Theilovirus/fisiologia , Carga Viral , Replicação Viral
17.
Clin Immunol ; 133(1): 27-44, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19559654

RESUMO

Interferon-beta is a current treatment for multiple sclerosis (MS). Interferon-beta is thought to exert its therapeutic effects on MS by down-modulating the immune response by multiple potential pathways. Here, we document that treatment of MS patients with interferon beta-1a (Rebif) results in a significant increase in the levels and function of the protein tyrosine phosphatase SHP-1 in PBMCs. SHP-1 is a crucial negative regulator of cytokine signaling, inflammatory gene expression, and CNS demyelination as evidenced in mice deficient in SHP-1. In order to examine the functional significance of SHP-1 induction in MS PBMCs, we analyzed the activity of proinflammatory signaling molecules STAT1, STAT6, and NF-kappaB, which are known SHP-1 targets. Interferon-beta treatment in vivo resulted in decreased NF-kappaB and STAT6 activation and increased STAT1 activation. Further analysis in vitro showed that cultured PBMCs of MS patients and normal subjects had a significant SHP-1 induction following interferon-beta treatment that correlated with decreased NF-kappaB and STAT6 activation. Most importantly, experimental depletion of SHP-1 in cultured PBMCs abolished the anti-inflammatory effects of interferon-beta treatment, indicating that SHP-1 is a predominant mediator of interferon-beta activity. In conclusion, interferon-beta treatment upregulates SHP-1 expression resulting in decreased transcription factor activation and inflammatory gene expression important in MS pathogenesis.


Assuntos
Interferon beta/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , NF-kappa B/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT6/metabolismo , Adulto , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Citocinas/sangue , Feminino , Inativação Gênica/imunologia , Humanos , Interferon beta-1a , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/imunologia , RNA Interferente Pequeno/imunologia , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT1/agonistas , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT6/antagonistas & inibidores , Fator de Transcrição STAT6/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
18.
Lab Invest ; 89(7): 742-59, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19398961

RESUMO

Recent studies in mice have demonstrated that the protein tyrosine phosphatase SHP-1 is a crucial negative regulator of proinflammatory cytokine signaling, TLR signaling, and inflammatory gene expression. Furthermore, mice genetically lacking SHP-1 (me/me) display a profound susceptibility to inflammatory CNS demyelination relative to wild-type mice. In particular, SHP-1 deficiency may act predominantly in inflammatory macrophages to increase CNS demyelination as SHP-1-deficient macrophages display coexpression of inflammatory effector molecules and increased demyelinating activity in me/me mice. Recently, we reported that PBMCs of multiple sclerosis (MS) patients have a deficiency in SHP-1 expression relative to normal control subjects indicating that SHP-1 deficiency may play a similar role in MS as to that seen in mice. Therefore, it became essential to examine the specific expression and function of SHP-1 in macrophages from MS patients. Herein, we document that macrophages of MS patients have deficient SHP-1 protein and mRNA expression relative to those of normal control subjects. To examine functional consequences of the lower SHP-1, the activation of STAT6, STAT1, and NF-kappaB was quantified and macrophages of MS patients showed increased activation of these transcription factors. In accordance with this observation, several STAT6-, STAT1-, and NF-kappaB-responsive genes that mediate inflammatory demyelination were increased in macrophages of MS patients following cytokine and TLR agonist stimulation. Supporting a direct role of SHP-1 deficiency in altered macrophage function, experimental depletion of SHP-1 in normal subject macrophages resulted in an increased STAT/NF-kappaB activation and increased inflammatory gene expression to levels seen in macrophages of MS patients. In conclusion, macrophages of MS patients display a deficiency of SHP-1 expression, heightened activation of STAT6, STAT1, and NF-kappaB and a corresponding inflammatory profile that may be important in controlling macrophage-mediated demyelination in MS.


Assuntos
Macrófagos/enzimologia , Esclerose Múltipla Recidivante-Remitente/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/deficiência , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Adulto , Sequência de Bases , Estudos de Casos e Controles , Citocinas/antagonistas & inibidores , Citocinas/genética , Citocinas/metabolismo , Primers do DNA/genética , Doenças Desmielinizantes/enzimologia , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/patologia , Feminino , Expressão Gênica , Humanos , Técnicas In Vitro , Inflamação/enzimologia , Inflamação/genética , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/genética , Esclerose Múltipla Recidivante-Remitente/patologia , NF-kappa B/metabolismo , Fenótipo , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT6/metabolismo
19.
J Virol ; 83(2): 522-39, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18987138

RESUMO

The protein tyrosine phosphatase SHP-1 is a crucial negative regulator of cytokine signaling and inflammatory gene expression, both in the immune system and in the central nervous system (CNS). Mice genetically lacking SHP-1 (me/me) display severe inflammatory demyelinating disease following inoculation with the Theiler's murine encephalomyelitis virus (TMEV) compared to infected wild-type mice. Therefore, it became essential to investigate the mechanisms of TMEV-induced inflammation in the CNS of SHP-1-deficient mice. Herein, we show that the expression of several genes relevant to inflammatory demyelination in the CNS of infected me/me mice is elevated compared to that in wild-type mice. Furthermore, SHP-1 deficiency led to an abundant and exclusive increase in the infiltration of high-level-CD45-expressing (CD45(hi)) CD11b(+) Ly-6C(hi) macrophages into the CNS of me/me mice, in concert with the development of paralysis. Histological analyses of spinal cords revealed the localization of these macrophages to extensive inflammatory demyelinating lesions in infected SHP-1-deficient mice. Sorted populations of CNS-infiltrating macrophages from infected me/me mice showed increased amounts of viral RNA and an enhanced inflammatory profile compared to wild-type macrophages. Importantly, the application of clodronate liposomes effectively depleted splenic and CNS-infiltrating macrophages and significantly delayed the onset of TMEV-induced paralysis. Furthermore, macrophage depletion resulted in lower viral loads and lower levels of inflammatory gene expression and demyelination in the spinal cords of me/me mice. Finally, me/me macrophages were more responsive than wild-type macrophages to chemoattractive stimuli secreted by me/me glial cells, indicating a mechanism for the increased numbers of infiltrating macrophages seen in the CNS of me/me mice. Taken together, these findings demonstrate that infiltrating macrophages in SHP-1-deficient mice play a crucial role in promoting viral replication by providing abundant viral targets and contribute to increased proinflammatory gene expression relevant to the effector mechanisms of macrophage-mediated demyelination.


Assuntos
Sistema Nervoso Central/imunologia , Inflamação/imunologia , Macrófagos/imunologia , Poliomielite/imunologia , Poliomielite/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/imunologia , Theilovirus/imunologia , Animais , Antígenos Ly/análise , Antígeno CD11b/análise , Ácido Clodrônico/farmacologia , Perfilação da Expressão Gênica , Fatores Imunológicos , Antígenos Comuns de Leucócito/análise , Procedimentos de Redução de Leucócitos , Macrófagos/química , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Knockout , Proteína Tirosina Fosfatase não Receptora Tipo 6/deficiência , Medula Espinal/patologia
20.
J Leukoc Biol ; 84(3): 631-43, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18552204

RESUMO

IL-33 is a novel member of the IL-1 cytokine family and a potent inducer of type 2 immunity, as mast cells and Th2 CD4+ T cells respond to IL-33 with the induction of type 2 cytokines such as IL-13. IL-33 mRNA levels are extremely high in the CNS, and CNS glia possess both subunits of the IL-33R, yet whether IL-33 is produced by and affects CNS glia has not been studied. Here, we demonstrate that pathogen-associated molecular patterns (PAMPs) significantly increase IL-33 mRNA and protein expression in CNS glia. Interestingly, IL-33 was localized to the nucleus of astrocytes. Further, CNS glial and astrocyte-enriched cultures treated with a PAMP followed by an ATP pulse had significantly higher levels of supernatant IL-1beta and IL-33 than cultures receiving any single treatment (PAMP or ATP). Supernatants from PAMP + ATP-treated glia induced the secretion of IL-6, IL-13, and MCP-1 from the MC/9 mast cell line in a manner similar to exogenous recombinant IL-33. Further, IL-33 levels and activity were increased in the brains of mice infected with the neurotropic virus Theiler's murine encephalomyelitis virus. IL-33 also had direct effects on CNS glia, as IL-33 induced various innate immune effectors in CNS glia, and this induction was greatly amplified by IL-33-stimulated mast cells. In conclusion, these results implicate IL-33-producing astrocytes as a potentially critical regulator of innate immune responses in the CNS.


Assuntos
Encéfalo/metabolismo , Infecções por Cardiovirus/metabolismo , Interleucinas/genética , Neuroglia/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Encéfalo/imunologia , Encéfalo/virologia , Infecções por Cardiovirus/virologia , Núcleo Celular/metabolismo , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Técnicas Imunoenzimáticas , Interleucina-1beta , Interleucina-33 , Interleucinas/metabolismo , Mastócitos/metabolismo , Mastócitos/virologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Neuroglia/virologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Theilovirus/genética , Theilovirus/metabolismo
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