RESUMEN
In inflammatory bowel disease (IBD), inflammation is sustained by an exaggerated response of lymphocytes. This results from enhanced expression of anti-apoptotic B cell lymphoma (BCL-2) and BCL-XL associated with a diminished turnover. Azathioprine (AZA) directly targets BCL-2 family-mediated apoptosis. We investigated whether the BCL-2 family expression pattern could be used to predict treatment response to AZA and determined whether BCL-2 inhibitor A-1211212 effectively diminishes lymphocytes and ameliorates inflammation in a model of colitis. BCL-2 family expression pattern was determined by next-generation sequencing (NGS). BCL-2 inhibitor was administered orally to Il10-/- mice. Haematological analyses were performed with an ADVIA 2120 and changes in immune cells were investigated using quantitative polymerase chain reaction (qPCR) and fluorescence activated cell sorter (FACS). We determined similar expression levels of BCL-2 family members in patients with remission and patients refractory to treatment, showing that BCL-2 family expression can not predict AZA treatment response. Expression was not correlated with the modified Truelove and Witts activity index (MTWAI). BCL-2 inhibitor initiated cell death in T cells from patients refractory to AZA and reduced lymphocyte count in Il10-/- mice. FACS revealed diminished CD8+ T cells upon BCL-2 inhibitor in Il10-/- mice without influencing platelets. Tnf, Il1ß, IfnÆ and Mcp-1 were decreased upon BCL-2 inhibitor. A-1211212 positively altered the colonic mucosa and ameliorated inflammation in mice. Pro-apoptotic BCL-2 inhibitor A-1211212 diminishes lymphocytes and ameliorates colitis in Il10-/- mice without inducing thrombocytopenia. BCL-2 inhibition could be a new therapy option for patients refractory to AZA.
Asunto(s)
Azatioprina/uso terapéutico , Colitis/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Linfocitos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Animales , Apoptosis , Células Cultivadas , Colitis/diagnóstico , Colitis/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Humanos , Mediadores de Inflamación/metabolismo , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/genética , Interleucina-10/genética , Linfocitos/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Resultado del TratamientoRESUMEN
INTRODUCTION: Chronic disease rates are produced from the Public Health Agency of Canada's Canadian Chronic Disease Surveillance System (CCDSS) using administrative health data from provincial/territorial health ministries. Denominators for these rates are based on estimates of populations derived from health insurance files. However, these data may not be accessible to all researchers. Another source for population size estimates is the Statistics Canada census. The purpose of our study was to calculate the major differences between the CCDSS and Statistics Canada's population denominators and to identify the sources or reasons for the potential differences between these data sources. METHODS: We compared the 2009 denominators from the CCDSS and Statistics Canada. The CCDSS denominator was adjusted for the growth components (births, deaths, emigration and immigration) from Statistics Canada's census data. RESULTS: The unadjusted CCDSS denominator was 34 429 804, 3.2% higher than Statistics Canada's estimate of population in 2009. After the CCDSS denominator was adjusted for the growth components, the difference between the two estimates was reduced to 431 323 people, a difference of 1.3%. The CCDSS overestimates the population relative to Statistics Canada overall. The largest difference between the two estimates was from the migrant growth component, while the smallest was from the emigrant component. CONCLUSION: By using data descriptions by data source, researchers can make decisions about which population to use in their calculations of disease frequency.
INTRODUCTION: Les taux de maladies chroniques du Système canadien de surveillance des maladies chroniques (SCSMC) de l'Agence de la santé publique du Canada sont fondés sur les données administratives sur la santé fournies par les ministères de la Santé des provinces et des territoires. Les dénominateurs utilisés pour calculer ces taux reposent sur des estimations de population tirées des dossiers d'assurance-maladie, données toutefois pas systématiquement accessibles à tous les chercheurs. Le recensement de Statistique Canada constitue quant à lui une autre source d'estimation de la taille de la population. Notre étude visait d'abord à calculer les principaux écarts entre les dénominateurs de population à partir des estimations du SCSMC et à partir de celles de Statistique Canada et ensuite à déterminer les causes à l'origine des écarts entre ces sources de données. MÉTHODOLOGIE: Nous avons comparé pour 2009 les dénominateurs fournis par le SCSMC et ceux fournis par Statistique Canada. Le dénominateur du SCSMC a été ajusté pour tenir compte des composantes de la croissance (naissances, décès, émigrants et immigrants) tirées des données de recensement de Statistique Canada. RÉSULTATS: Le dénominateur non ajusté du SCSMC était de 34 429 804 personnes, soit une différence de + 3,2 % par rapport à l'estimation de population de Statistique Canada pour 2009. Après ajustement du dénominateur du SCSMC pour tenir compte des composantes de la croissance, la différence entre les deux estimations s'est trouvé réduite à 431 323 personnes, soit un écart de 1,3 %. L'estimation tirée du SCSMC constitue une surestimation par rapport à celle de Statistique Canada. Le plus grand écart entre les deux estimations relève de la composante de croissance liée à l'immigration, alors que l'écart le moindre provient de la composante de croissance liée à la population émigrante. CONCLUSION: Disposant des descriptions de données par source de données, les chercheurs peuvent choisir quelle estimation de la population utiliser dans leurs calculs des fréquences de maladies.
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Censos , Enfermedad Crónica/epidemiología , Seguro de Salud/estadística & datos numéricos , Población , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Canadá/epidemiología , Causas de Muerte , Niño , Preescolar , Enfermedad Crónica/mortalidad , Bases de Datos Factuales/estadística & datos numéricos , Diabetes Mellitus/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Persona de Mediana Edad , Prevalencia , Adulto JovenRESUMEN
Exaggerated activation of lymphocytes contributes to the pathogenesis of inflammatory bowel disease (IBD). Medical therapies are linked to the BCL-2 family-mediated apoptosis. Imbalance in BCL-2 family proteins may cause failure in therapeutic responses. We investigated the role of BCL-2 inhibitor ABT-737 for lymphocyte apoptosis in mice under inflammatory conditions. B.6129P2-interleukin (IL)-10(tm1Cgn) /J (IL-10(-/-) ) weighing 25-30 g with ongoing colitis were used. Fifty mg/kg/day ABT-737 was injected intraperitoneally (i.p.). Haematological analyses were performed with an ADVIA 2120 flow cytometer and mass cytometry with a CyTOF 2. Following i.p. administration, ABT-737 was detected in both spontaneous and acute colitis in peripheral blood (PBL) and colon tissue. Treatment led to lymphopenia. CD4(+) CD44(+) CD62L(+) central memory and CD8(+) , CD44(+) CD62L(-) central memory T cells were decreased in PBL upon ABT-737 compared to vehicle-receiving controls. Increased apoptosis upon ABT-737 was determined in blood lymphocytes, splenocytes and Peyer's patches and was accompanied by a decrease in TNF and IL-1B. ABT-737 positively altered the colonic mucosa and ameliorated inflammation, as shown by colonoscopy, histology and colon length. A decreased BIM/BCL-2 ratio or absence of BIM in both Bim(-) (/) (-) and Il10(-) (/) (-) × Bim(-) (/) (-) impeded the protective effect of ABT-737. The BIM/BCL-2 ratio decreased with age and during the course of treatment. Thus, long-term treatment resulted in adapted TNF levels and macroscopic mucosal damage. ABT-737 was efficacious in diminishing lymphocytes and ameliorating colitis in a BIM-dependent manner. Regulation of inappropriate survival of lymphocytes by ABT-737 may provide a therapeutic strategy in IBD.
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Proteínas Reguladoras de la Apoptosis/genética , Compuestos de Bifenilo/farmacología , Colitis/tratamiento farmacológico , Proteínas de la Membrana/genética , Nitrofenoles/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas/genética , Sulfonamidas/farmacología , Animales , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 11 Similar a Bcl2 , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Colitis/inducido químicamente , Colitis/genética , Colitis/patología , Sulfato de Dextran , Femenino , Expresión Génica , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Inyecciones Intraperitoneales , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Selectina L/genética , Selectina L/metabolismo , Linfopenia/inducido químicamente , Linfopenia/genética , Linfopenia/patología , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Piperazinas/farmacología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Historically, many species moved great distances as climates changed. However, modern movements will be limited by the patterns of human-dominated landscapes. Here, we use a combination of projected climate-driven shifts in the distributions of 2903 vertebrate species, estimated current human impacts on the landscape, and movement models, to determine through which areas in the western hemisphere species will likely need to move to track suitable climates. Our results reveal areas with projected high densities of climate-driven movements - including, the Amazon Basin, the southeastern United States and southeastern Brazil. Some of these regions, such as southern Bolivia and northern Paraguay, contain relatively intact landscapes, whereas others such as the southeastern United States and Brazil are heavily impacted by human activities. Thus, these results highlight both critical areas for protecting lands that will foster movement, and barriers where human land-use activities will likely impede climate-driven shifts in species distributions.
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Distribución Animal , Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Vertebrados/fisiología , Anfibios/fisiología , Animales , Aves/fisiología , América Central , Mapeo Geográfico , Actividades Humanas , Humanos , Mamíferos/fisiología , Mapas como Asunto , América del Norte , América del SurRESUMEN
We examined the effects of habitat discontinuities on gene flow among puma (Puma concolor) populations across the southwestern USA. Using 16 microsatellite loci, we genotyped 540 pumas sampled throughout the states of Utah, Colorado, Arizona, and New Mexico, where a high degree of habitat heterogeneity provides for a wide range of connective habitat configurations between subpopulations. We investigated genetic structuring using complementary individual- and population-based analyses, the latter employing a novel technique to geographically cluster individuals without introducing investigator bias. The analyses revealed genetic structuring at two distinct scales. First, strikingly strong differentiation between northern and southern regions within the study area suggests little migration between them. Second, within each region, gene flow appears to be strongly limited by distance, particularly in the presence of habitat barriers such as open desert and grasslands. Northern pumas showed both reduced genetic diversity and greater divergence from a hypothetical ancestral population based on Bayesian clustering analyses, possibly reflecting a post-Pleistocene range expansion. Bayesian clustering results were sensitive to sampling density, which may complicate inference of numbers of populations when using this method. The results presented here build on those of previous studies, and begin to complete a picture of how different habitat types facilitate or impede gene flow among puma populations.
Asunto(s)
Demografía , Ambiente , Genética de Población , Puma/genética , Animales , Teorema de Bayes , Análisis por Conglomerados , Frecuencia de los Genes , Genotipo , Geografía , Repeticiones de Microsatélite/genética , Dinámica Poblacional , Sudoeste de Estados UnidosAsunto(s)
Inhibidores Enzimáticos/farmacología , Rechazo de Injerto/prevención & control , Trasplante de Corazón/inmunología , Inmunosupresores/farmacología , Trasplante de Islotes Pancreáticos/inmunología , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/antagonistas & inhibidores , Animales , Animales Recién Nacidos , Citocinas/biosíntesis , Diabetes Mellitus Experimental/cirugía , Relación Dosis-Respuesta a Droga , Femenino , Hipersensibilidad Tardía/inmunología , Terapia de Inmunosupresión/métodos , Interleucina-2/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Trasplante de Piel/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Trasplante HomólogoRESUMEN
Dendritic cell (DC) precursors and immature DC reside in epithelium where they encounter pathogens and cytokines, which stimulate their differentiation. We hypothesized that type-I interferons (IFN-alpha and -beta), cytokines that are produced early in the innate immune response against viruses and some bacteria, may influence DC differentiation and function. To examine this possibility, we used an in vitro model of DC differentiation in which initial culture of human CD14(+) monocytes with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-4 generates immature DC, and subsequent culture with tumor necrosis factor (TNF)-alpha drives the final development into mature DC. We found in this model that IFN-alpha/beta, added from the initiation of the culture on, significantly reduced the survival and altered the morphology and differentiation of DC. TNF-alpha-dependent maturation of IFN-beta-treated immature DC led to cells with reduced expression of CD1a, CD40, CD54, and CD80 when compared with mature DC controls. IFN-alpha/beta-treated DC further had a reduced capacity to induce naive Th-cell proliferation through allostimulation or anti-CD3 monoclonal antibody stimulation. In addition, IFN-alpha/beta-treated DC secreted less IL-12 upon stimulation with Staphylococcus aureus Cowan strain or with CD4(+) T cells, and this decrease correlated directly with their inability to support CD4(+) T-cell secretion of IFN-gamma, even though T-cell lymphotoxin production was unaffected. These findings indicate that type-I IFNs can influence the generation of acquired immune responses by modifying T-helper cell differentiation through the regulation of DC differentiation and function.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/citología , Células Dendríticas/inmunología , Interferón Tipo I/farmacología , Interferón-alfa/farmacología , Receptores de Lipopolisacáridos/sangre , Monocitos/citología , Antígenos CD/sangre , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/inmunología , Células Cultivadas , Células Dendríticas/efectos de los fármacos , Humanos , Inmunocompetencia , Interleucina-2/biosíntesis , Cinética , Activación de Linfocitos , Monocitos/efectos de los fármacos , Monocitos/inmunología , Proteínas RecombinantesAsunto(s)
Linfocitos T CD4-Positivos/citología , Diferenciación Celular , Células TH1/citología , Células Th2/citología , Anticuerpos Monoclonales , Linfocitos T CD4-Positivos/inmunología , Separación Celular/métodos , Células Dendríticas/citología , Células Dendríticas/inmunología , Humanos , Monocitos/citología , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunología , Células TH1/inmunología , Células Th2/inmunologíaRESUMEN
We have previously shown that IFN-beta, a key cytokine associated with the early phase of the innate host defense, can prevent the generation of human Th1 cells. Specifically, we demonstrated that IFN-beta prevents the in vitro monocyte-derived mature dendritic cell (DC)-dependent differentiation of naive Th cells into IFN-gamma-secreting Th cells, as a result of its ability to inhibit DC IL-12 secretion. The goal of the present study was to identify how IFN-beta negatively regulates IL-12 secretion by DC. We report that in our Th cell differentiation model, DC IL-12 secretion is dependent on the CD40L/CD40 accessory pathway, and, utilizing a Th cell-free system, we find that IFN-beta inhibits anti-CD40 mAb-induced DC secretion of the p40 chain of the IL-12 heterodimer. In addition, we show that IFN-beta-mediated inhibition of CD40 signaling does not interfere with all signaling pathways emanating from CD40, since anti-CD40 mAb-induced DC IL-6 secretion is augmented by IFN-beta. Thus, our results demonstrate that signaling from CD40 is differentially regulated by IFN-beta. A second critical element of innate immunity involves the response against components of bacterial membranes such as LPS. DC respond to LPS by secreting IL-6 and IL-12. In contrast to CD40-dependent IL-6 and IL-12 secretion, we find that LPS-induced DC secretion of p40 IL-12 and IL-6 is not affected by IFN-beta. Our findings show that IFN-beta influences the generation of acquired immune responses through its regulation of CD40-dependent DC functions.
Asunto(s)
Adyuvantes Inmunológicos/fisiología , Antígenos CD40/fisiología , Citocinas/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Interferón beta/fisiología , Citocinas/antagonistas & inhibidores , Citocinas/biosíntesis , Sinergismo Farmacológico , Humanos , Interleucina-12/antagonistas & inhibidores , Interleucina-12/biosíntesis , Interleucina-12/metabolismo , Interleucina-6/antagonistas & inhibidores , Interleucina-6/biosíntesis , Interleucina-6/metabolismo , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Transducción de Señal/inmunología , Linfocitos T/inmunologíaRESUMEN
Mycosis fungoides is a low-grade cutaneous T-cell lymphoma. Early treatment often involves the use of topical chemotherapy such as mechlorethamine or carmustine although single-agent oral chemotherapy with alkylators is common for advanced disease. Recently, in a Phase I study of the new alkylating agent temozolomide, two mycosis fungoides patients experienced a complete response. The mechanism of resistance to alkylating drugs such as temozolomide is thought to be due to the presence in tumor cells of the DNA repair protein, O6-alkylguanine-DNA alkyltransferase (AGT). The protein mediates a reaction with the O6-position of guanine in DNA, removing the lesion and leaving guanine intact. We, therefore, examined the levels of AGT in CD4+ T lymphocytes obtained by negative antibody selection from the blood of noncancerous individuals and mycosis fungoides patients, and in paraffin-embedded sections from mycosis fungoides patch, plaque, or tumor lesions and cells from involved lymph nodes. AGT protein levels were measured by quantitative immunofluorescence microscopy using a monoclonal antibody against human AGT. Using this approach, the mean level of our positive control (AGT-expressing cells) was 84,807 molecules/nucleus; values below 5,000 molecules/nucleus are considered very low. The mean AGT level in CD4+ T lymphocytes from noncancerous and cancerous individuals was 18,618 (n = 12) and 8,593 (n = 5), respectively. The mean fraction of outliers in circulating CD4+ T lymphocytes from mycosis fungoides patients was statistically significantly lower than T cells in lymph nodes. AGT molecules/nucleus from lymph node biopsies from 8 of 10 patients showed low (< 10,000 molecules/nucleus) or undetectable levels (n = 5) of AGT. The mean AGT level from samples of mycosis fungoides patch/plaque and tumor was also low at 221 (n = 4) and 2,363 (n = 6), respectively. Surprisingly, Hut78, a mycosis fungoides T-cell lymphoma cell line, was positive for AGT activity (median: 77,700 molecules/nucleus), and Hut102--another mycosis fungoides cell line--was low (median: 5,990 molecules/nucleus). Because AGT is a primary means of cell resistance to alkylating agents, the low level of AGT in neoplastic T lymphocytes from patients with mycosis fungoides suggests that treatment with alkylating agents producing O6-alkylguanine adducts, such as carmustine or temozolomide, may produce improved clinical outcomes.
Asunto(s)
Alquilantes/uso terapéutico , Micosis Fungoide/enzimología , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , Neoplasias Cutáneas/enzimología , Adulto , Anciano , Anciano de 80 o más Años , Linfocitos T CD4-Positivos/enzimología , Línea Celular , Núcleo Celular/enzimología , Femenino , Citometría de Flujo , Humanos , Separación Inmunomagnética , Ganglios Linfáticos/enzimología , Masculino , Microscopía Fluorescente , Persona de Mediana Edad , Micosis Fungoide/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológicoRESUMEN
We have investigated the role of type I IFNs (IFN-alpha and -beta) in human T cell differentiation using anti-CD3 mAb and allogeneic, in vitro-derived dendritic cells (DC) as APCs. DC were very efficient activators of naive CD4+ T cells, providing necessary costimulation and soluble factors to support Th1 differentiation and expansion. Addition of IFN-alphabeta to DC/T cell cultures resulted in induction of T cell IL-10 production and inhibition of IFN-gamma, TNF-alpha, and LT secretion. Diminished T cell IFN-gamma production correlated with IFN-alphabeta-mediated inhibition of the p40 chain of the IL-12 heterodimer secreted by DC. Suppression of p40 IL-12 and IFN-gamma was not due to increased levels of IL-10 in these cultures, and production of IFN-gamma could be restored by exogenous IL-12. These data indicate that type I IFNs inhibit DC p40 IL-12 expression, which is required for development of IFN-gamma-producing CD4+ T cells. Furthermore, when T cells were restimulated without IFN-beta, these cells induced less p40 IL-12 from DC, suggesting that the functional properties of T cells may regulate DC function. Thus, IFN-alphabeta inhibits both IL-12-dependent and independent Th1 cytokine production and provides a mechanism for inhibition of IL-12-mediated immunity in viral infections.
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Células Dendríticas/inmunología , Interferón Tipo I/farmacología , Interferón beta/farmacología , Interleucina-12/biosíntesis , Células TH1/inmunología , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Humanos , Interleucina-10/biosíntesis , Interleucina-10/inmunología , Interleucina-12/inmunología , Proteínas Recombinantes/farmacología , Células TH1/citologíaRESUMEN
Our previous work has shown that specific peripheral immune tolerance induced by the intravenous administration of ECDI-fixed, antigen-coupled syngeneic splenocytes is an extremely efficient method for prevention and treatment of chronic relapsing experimental autoimmune encephalomyelitis (R-EAE) in susceptible SJL/J mice. The current study examined the mechanisms by which unresponsiveness is induced in primed encephalitogenic T cells. The results indicate that the inhibition of MBP-specific T cells by the i.v. injection of MBP-coupled splenocytes is not due to the induction of antigen-specific regulatory T cells, but rather to the induction of anergy/deletion of the effector cells. This conclusion is supported by the findings that spleen or lymph node cells isolated from MBP-tolerant mice fail to inhibit the adoptive transfer of R-EAE in cotransfer assays, and that tolerance is not inhibited by prior thymectomy or prior treatment with cyclophosphamide or anti-CD8 monoclonal antibody. In contrast, we demonstrate that splenocytes from MBP-tolerized, asymptomatic mice have a significantly reduced ability to serially transfer R-EAE to naive secondary recipients following antigen re-activation in vitro, in the first several weeks following tolerization, but that the ability to serially transfer R-EAE returns to sham tolerant control levels within 1-2 months. We also demonstrate a significantly reduced precursor frequency of MBP-specific, IL-2-producing T cells in the MBP-tolerant within three days of treatment. Collectively, the data most closely support a model wherein inhibition of MBP-specific encephalitogenic CD4+ effector T cells by i.v. injected MBP-coupled splenocytes is due to the direct induction of anergy/deletion from which they can recover over time.
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Autoantígenos/inmunología , Anergia Clonal/inmunología , Supresión Clonal/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Proteína Básica de Mielina/inmunología , Linfocitos T Reguladores/inmunología , Traslado Adoptivo , Animales , Autoantígenos/administración & dosificación , Bovinos , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos , Proteína Básica de Mielina/administración & dosificación , Ratas , Bazo/citología , Bazo/efectos de los fármacos , Bazo/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Factores de TiempoRESUMEN
Type I interferons (IFN) are important regulators of both innate and acquired immunity. We have used an in vitro system of human CD4+ T cell differentiation to determine how IFN-beta influences development of T helper (Th) subsets and homing receptor expression. IFN-beta promoted differentiation of CD4+ T cells that produce low levels of both IFN-gamma and lymphotoxin compared to interleukin (IL)-12-derived Th1 CD4+ T cells. IFN-beta inhibited production of Th2 cytokines (IL-5 and IL-13) and augmented IL-12-mediated IL-10 secretion. In addition, IFN-beta significantly enhanced L-selection expression on CD4+ T cells and synergized with IL-12 to induce expression of cutaneous lymphocyte-associated antigen (CLA). This Th1 L-selectin+, CLA+ phenotype is characteristic of T cells found in normal human skin and suggests a role for type I IFN in the regulation of Th subset differentiation and tissue-specific homing receptors.
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Regulación de la Expresión Génica/efectos de los fármacos , Interferón beta/farmacología , Linfocinas/biosíntesis , Receptores Mensajeros de Linfocitos/biosíntesis , Células TH1/efectos de los fármacos , Células Th2/efectos de los fármacos , Antígenos de Diferenciación de Linfocitos T , Antígenos de Neoplasias , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Humanos , Interleucina-10/biosíntesis , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-12/farmacología , Interleucina-13/biosíntesis , Interleucina-13/genética , Interleucina-13/metabolismo , Interleucina-5/biosíntesis , Interleucina-5/genética , Interleucina-5/metabolismo , Selectina L/biosíntesis , Selectina L/genética , Linfocinas/genética , Linfocinas/metabolismo , Linfotoxina-alfa/biosíntesis , Linfotoxina-alfa/genética , Linfotoxina-alfa/metabolismo , Glicoproteínas de Membrana/biosíntesis , Glicoproteínas de Membrana/genética , Especificidad de Órganos , Fenotipo , Receptores Mensajeros de Linfocitos/genética , Proteínas Recombinantes de Fusión/farmacología , Células TH1/metabolismo , Células Th2/metabolismoRESUMEN
Peptide-specific tolerance with PLP139-151 peptide analogs was used to compare the fine antigen-specificity requirements at both the inductive and effector phases of relapsing EAE (R-EAE). A PLP139-151 analog peptide containing a single substitution at the primary T cell receptor (TcR) contact residue (A144) did not induce proliferation in PLP139-151-primed CD4+ T cells. In addition, tolerance induced with ECDI-treated. A144-coupled splenocytes failed to prevent the inductive phase of PLP139-151-induced R-EAE or to inhibit the induction of peptide-specific DTH indicating that naive PLP139-151-specific T cells do not react with the A144 peptide analog. In contrast, A144-coupled splenocytes did prevent the expression of the effector phase of R-EAE and inhibited the elicitation of peptide-specific DTH responses upon administration to mice seven days after immunization with PLP139-151. The results provide in vivo evidence that "antigen-experienced' T cells recognize a broader repertoire of antigens than do naive T cells and have important implications for the regulation of immune responses and for advancing our understanding of the pathogenesis and treatment of autoimmune disease.
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Antígenos/inmunología , Linfocitos T CD4-Positivos/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Proteína Proteolipídica de la Mielina , Linfocitos T Reguladores/inmunología , Secuencia de Aminoácidos , Animales , Femenino , Hipersensibilidad Tardía/inmunología , Hipersensibilidad Tardía/prevención & control , Ratones , Ratones Endogámicos , Proteínas de la Mielina/genética , Proteínas de la Mielina/inmunología , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/inmunologíaRESUMEN
Studies on the impacts of violence often overlook the moderating role of social or demographic variables and the confounding effects of different victimization experiences on the same individual. In the present study, 93 adult women presenting to an urban psychiatric emergency room were interviewed regarding their lifetime victimization history, and their charts were examined for relevant demographic and psychiatric variables. Self-reported childhood sexual and physical abuse were common in this sample (53% and 42%, respectively). Adult physical assaults outside of a relationship were described by 29% of patients, 37% reported adult sexual assaults or rapes, and 42% stated that they had experienced one or more physical assaults within an adult relationship. Childhood and adult victimization experiences were intercorrelated and were associated with certain sociodemographic variables. Logistic regression analyses indicated that both child abuse and adult assaults were uniquely associated with psychiatric difficulties, even after controlling for relevant background variables. Childhood sexual abuse was the most powerful predictor of later psychiatric symptoms and disorders.
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Maltrato a los Niños/estadística & datos numéricos , Servicios de Urgencia Psiquiátrica/estadística & datos numéricos , Trastornos Mentales/diagnóstico , Violencia , Adulto , Factores de Edad , Niño , Abuso Sexual Infantil/estadística & datos numéricos , Estudios de Cohortes , Comorbilidad , Femenino , Registros de Hospitales , Humanos , Estado Civil , Trastornos Mentales/epidemiología , Trastornos Mentales/psicología , Evaluación de Resultado en la Atención de Salud , Grupos Raciales , Factores SexualesRESUMEN
Experimental autoimmune encephalomyelitis (EAE) is a CD4+ T cell-mediated, inflammatory demyelinating disease of the central nervous system (CNS) that serves as a model for the human demyelinating disease, multiple sclerosis. A critical event in the pathogenesis of EAE is the entry of both Ag-specific T lymphocytes and Ag-nonspecific mononuclear cells into the CNS. In the present report we investigated the role of two C-C chemokines (macrophage inflammatory protein-1 alpha (MIP-1 alpha) and monocyte chemotactic protein-1) and a C-x-C chemokine (MIP-2) in the pathogenesis of EAE. Production in the CNS of MIP-1 alpha, but not that of MIP-2, a rodent homologue of IL-8, or monocyte chemotactic protein-1, correlated with development of severe clinical disease. Administration of anti-MIP-1 alpha, but not that of anti-monocyte chemotactic protein-1, prevented the development of both acute and relapsing paralytic disease as well as infiltration of mononuclear cells into the CNS initiated by the transfer of neuroantigen peptide-activated T cells. Ab therapy could also be used to ameliorate the severity of ongoing clinical disease. Anti-MIP-1 alpha did not affect the activation of encepahlitogenic T cells as measured by cytokine secretion, surface marker expression, and ability to adoptively transfer EAE. These results demonstrate that MIP-1 alpha plays an important role in directing the chemoattraction of mononuclear inflammatory cells in the T cell-mediated autoimmune disease, EAE.
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Quimiocina CCL2/inmunología , Citocinas/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Monocinas/inmunología , Linfocitos T/inmunología , Animales , Anticuerpos/uso terapéutico , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/metabolismo , Quimiocina CCL4 , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/prevención & control , Femenino , Proteínas Inflamatorias de Macrófagos , RatonesRESUMEN
The role of epitope spreading in the pathology of relapsing-remitting experimental autoimmune encephalomyelitis (R-EAE) was examined. Using peripherally induced immunologic tolerance as a probe to analyze the neuropathologic T cell repertoire, we show that the majority of the immunopathologic reactivity during the acute phase of R-EAE in SJL/J mice induced by active immunization with the intact proteolipid (PLP) molecule is directed at the PLP139-151 epitope and that responses to secondary encephalitogenic PLP epitopes may contribute to the later relapsing phases of disease. Intermolecular epitope spreading was demonstrated by showing the development of T cell responses to PLP139-151 after acute disease in mice in which R-EAE was initiated by the transfer of T cells specific for the non-cross-reactive MBP84-104 determinant. Intramolecular epitope spreading was demonstrated by showing that endogenous host T cells specific for a secondary encephalitogenic PLP epitope (PLP178-191) are demonstrable by both splenic T cell proliferative and in vivo delayed-type hypersensitivity responses in mice in which acute central nervous system damage was initiated by T cells reactive with the immunodominant, non-cross-reactive PLP139-151 sequence. The PLP178-191-specific responses are activated as a result of and correlate with the degree of acute tissue damage, since they do not develop in mice tolerized to the initiating epitope before expression of acute disease. Most importantly, we show that the PLP178-191-specific responses are capable of mediating R-EAE upon adoptive secondary transfer to naive recipient mice. Furthermore, induction of tolerance to intact PLP (which inhibits responses to both the initiating PLP139-151 epitope and to the PLP178-191 epitope) after the acute disease episode is sufficient to prevent relapsing disease. These results strongly support a contributory role of T cell responses to epitopes released as a result of acute tissue damage to the immunopathogenesis of relapsing clinical episodes and have important implications for the design of antigen-specific immunotherapies for the treatment of chronic autoimmune disorders in humans.
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Enfermedades Autoinmunes/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Epítopos Inmunodominantes/inmunología , Proteínas de la Mielina/inmunología , Fragmentos de Péptidos/inmunología , Células TH1/inmunología , Enfermedad Aguda , Secuencia de Aminoácidos , Animales , Enfermedades Autoinmunes/patología , Enfermedades Autoinmunes/terapia , Reacciones Cruzadas , Desensibilización Inmunológica , Encefalomielitis Autoinmune Experimental/patología , Encefalomielitis Autoinmune Experimental/terapia , Femenino , Inmunoterapia Adoptiva , Activación de Linfocitos , Ratones , Ratones Endogámicos , Datos de Secuencia Molecular , Proteína Básica de Mielina/inmunología , Proteínas de la Mielina/uso terapéutico , Proteínas de la Mielina/toxicidad , Proteína Proteolipídica de la Mielina , Fragmentos de Péptidos/uso terapéutico , Fragmentos de Péptidos/toxicidad , Recurrencia , Células TH1/trasplanteRESUMEN
CD4+ T cells specific for PLP 139-151 induce a relapsing-remitting form of EAE which is similar to the human demyelinating disease multiple sclerosis (MS) in both clinical course and histopathology. Conservative and nonconservative amino acid substitutions were introduced at three TcR or MHC contact residues within PLP 139-151 to identify fine specificity requirements, at the polyclonal level, for stimulating naive encephalitogenic T cells and for reactivating pre-primed autoreactive T cells as measured by T cell proliferation, cytokine induction, and functional encephalitogenic potential. The results indicate that peptides with substitutions at position 145 exhibited a significantly diminished ability to induce active disease, but these substitutions had little or no effect on the ability to activate PLP 139-151-primed T cells for proliferation or disease transfer. A conservative or a nonconservative substitution at position 144 ablated both encephalitogenic potential in active and adoptive EAE models and the ability to induce proliferative responses in T cells primed to the native peptide. A nonconservative lysine for glycine, but not a conservative serine substitution, at position 146 had similar effects. In contrast to their inability to induce active EAE and stimulate in vitro proliferation of PLP 139-151-primed T cells, the Y144 and the 146 analog peptides were able to suboptimally reactivate these cells for transfer of adoptive EAE. Furthermore, the nonencephalitogenic K146 peptide was found to exacerbate in vivo induction of EAE induced by priming with a suboptimal dose of PLP 139-151. These data support the hypothesis that naive neuroantigen-specific CD4+ T cells have more stringent activation requirements than do PLP 139-151-specific T cells which have previously encountered antigen. The finding that the analog peptides induced differential patterns of cytokine production, with LT/TNF-alpha production but not IFN-gamma production correlating with full encephalitogenic potential, suggests different functional outcomes may result from differential levels of signal transduction triggered by the substituted peptides. The significance of these results to the potential development of autoimmune disease via molecular mimicry and for the development of new strategies for preventing and treating T cell-mediated autoimmune diseases is discussed.
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Linfocitos T CD4-Positivos/inmunología , Epítopos , Activación de Linfocitos , Proteínas de la Mielina/inmunología , Proteína Proteolipídica de la Mielina , Fragmentos de Péptidos/inmunología , Péptidos/inmunología , Animales , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/trasplante , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Linfocinas/metabolismo , Ratones , Ratones Endogámicos , Péptidos/química , Recurrencia , Valores de ReferenciaRESUMEN
Fig. 6 depicts a model for epitope spreading in T cell-mediated demyelination. The acute phase of disease is due to T cells specific for the initiating epitope, which can be either a determinant on the CNS target organ of the autoimmune response or a determinant on a persisting, CNS-tropic virus. The primary T cell response is responsible for the initial tissue damage by the production of proinflammatory Th1 cytokines which can affect myelination directly (Selmaj et al. 1991) and indirectly by their ability to recruit and activate macrophages to phagocytize myelin (Cammer et al. 1978). As a result of myelin damage and opening of the blood-brain-barrier during acute disease, T cells specific for endogenous epitopes on the same and/or different myelin proteins are primed and expand either in the periphery or locally in the CNS. These secondary T cells initiate an additional round of myelin destruction, leading to a clinical relapse by production of additional pro-inflammatory cytokines, similar to the bystander demyelination operative during acute disease. It will be of great interest to determine the relative contributions of local and systemic immune responses to these endogenous neuroepitopes. It is possible that local CNS presentation of endogenous neuroepitopes following acute CNS damage could be mediated by infiltrating inflammatory macrophages, activated microglial cells, endothelial cells and/or astrocytes. These tissue resident antigen presenting cells have been shown to upregulate expression of MHC class II (Sakai et al. 1986, Traugott & Lebon 1988), certain adhesion molecules (Cannella et al. 1990), and B7 costimulatory molecules (K. M. Nikcevich, J. A. Bluestone, and S. D. Miller, in preparation) in response to pro-inflammatory cytokines. The data on epitope spreading provided by the murine demyelinating disease models clearly illustrate the dynamic nature of the T cell repertoire during chronic inflammation in a specific target organ. The contribution of epitope spreading to chronic CNS demyelination could be considered to be a special case since tolerance to myelin epitopes would be expected to be inefficient due to their sequestration behind the blood-brain-barrier. However, the recent description of epitope spreading in response to pancreatic antigens in spontaneous diabetes in the NOD mouse may indicate that this phenomenon is operative in a variety of organ-specific experimental and spontaneous autoimmune diseases.(ABSTRACT TRUNCATED AT 400 WORDS)