RESUMEN
Lymphotoxin α (LTα) is a soluble factor produced by activated lymphocytes which is cytotoxic to tumor cells. Although a promising candidate in cancer therapy, the application of recombinant LTα has been limited by its instability and toxicity by systemic administration. Secreted LTα interacts with several distinct receptors for its biological activities. Here, we report a TNFR1-selective human LTα mutant (LTα Q107E) with potent antitumor activity. Recombinant LTα Q107E with N-terminal 23 and 27 aa deletion (named LTα Q1 and Q2, respectively) showed selectivity to TNFR1 in both binding and NF-κB pathway activation assays. To test the therapeutic potential, we constructed an oncolytic adenovirus (oAd) harboring LTα Q107E Q2 mutant (named oAdQ2) and assessed the antitumor effect in mouse xenograft models. Intratumoral delivery of oAdQ2 inhibited tumor growth. In addition, oAdQ2 treatment enhanced T cell and IFNγ-positive CD8 T lymphocyte infiltration in a human PBMC reconstituted-SCID mouse xenograft model. This study provides evidence that reengineering of bioactive cytokines with tissue or cell specific properties may potentiate their therapeutic potential of cytokines with multiple receptors.
Asunto(s)
Adenoviridae , Inmunoterapia , Linfotoxina-alfa , Ratones SCID , Viroterapia Oncolítica , Receptores Tipo I de Factores de Necrosis Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Humanos , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Animales , Ratones , Linfotoxina-alfa/genética , Adenoviridae/genética , Viroterapia Oncolítica/métodos , Inmunoterapia/métodos , Virus Oncolíticos/genética , Línea Celular Tumoral , Neoplasias/terapia , Neoplasias/inmunología , Neoplasias/genética , Mutación , Linfocitos T CD8-positivos/inmunología , FN-kappa B/metabolismoRESUMEN
Regulatory T cells (Treg) are critical players of immune tolerance that develop in the thymus via two distinct developmental pathways involving CD25+Foxp3- and CD25-Foxp3lo precursors. However, the mechanisms regulating the recently identified Foxp3lo precursor pathway remain unclear. Here, we find that the membrane-bound lymphotoxin α1ß2 (LTα1ß2) heterocomplex is upregulated during Treg development upon TCR/CD28 and IL-2 stimulation. We show that Lta expression limits the maturational development of Treg from Foxp3lo precursors by regulating their proliferation, survival, and metabolic profile. Transgenic reporter mice and transcriptomic analyses further reveal that medullary thymic epithelial cells (mTEC) constitute an unexpected source of IL-4. We demonstrate that LTα1ß2-lymphotoxin ß receptor-mediated interactions with mTEC limit Treg development by down-regulating IL-4 expression in mTEC. Collectively, our findings identify the lymphotoxin axis as the first inhibitory checkpoint of thymic Treg development that fine-tunes the Foxp3lo Treg precursor pathway by limiting IL-4 availability.
Asunto(s)
Factores de Transcripción Forkhead , Interleucina-4 , Receptor beta de Linfotoxina , Linfotoxina-alfa , Transducción de Señal , Linfocitos T Reguladores , Animales , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Factores de Transcripción Forkhead/metabolismo , Factores de Transcripción Forkhead/genética , Interleucina-4/metabolismo , Ratones , Linfotoxina-alfa/metabolismo , Linfotoxina-alfa/genética , Receptor beta de Linfotoxina/metabolismo , Receptor beta de Linfotoxina/genética , Timo/inmunología , Timo/citología , Timo/metabolismo , Células Epiteliales/metabolismo , Ratones Endogámicos C57BL , Diferenciación Celular , Ratones Transgénicos , Interleucina-2/metabolismo , Proliferación Celular , Heterotrímero de Linfotoxina alfa1 y beta2/metabolismo , Heterotrímero de Linfotoxina alfa1 y beta2/genéticaRESUMEN
OBJECTIVES: The mechanism that leads to disseminated tuberculosis in HIV-negative patients is still largely unknown. T cell subsets and signaling pathways that were associated with disseminated tuberculosis were investigated. METHODS: Single-cell profiling of whole T cells was performed to identify T cell subsets and enriched signaling pathways that were associated with disseminated tuberculosis. Flow cytometric analysis and blocking experiment were used to investigate the findings obtained by transcriptome sequencing. RESULTS: Patients with disseminated tuberculosis had depleted Th1, Tc1 and Tc17 cell subsets, and IFNG was the most down-regulated gene in both CD4 and CD8 T cells. Gene Ontology analysis showed that non-canonical NF-κB signaling pathway, including NFKB2 and RELB genes, was significantly down-regulated and was probably associated with disseminated tuberculosis. Expression of several TNF superfamily ligands and receptors, such as LTA and TNF genes, were suppressed in patients with disseminated tuberculosis. Blocking of TNF-α and soluble LTα showed that TNF-α was involved in IFN-γ production and LTα influenced TNF-α expression in T cells. CONCLUSIONS: Impaired T cell IFN-γ response mediated by suppression of TNF and non-canonical NF-κB signaling pathways might be responsible for disseminated tuberculosis.
Asunto(s)
Interferón gamma , FN-kappa B , Transducción de Señal , Factor de Necrosis Tumoral alfa , Humanos , Masculino , Femenino , Adulto , FN-kappa B/metabolismo , Persona de Mediana Edad , Interferón gamma/metabolismo , Interferón gamma/genética , Interferón gamma/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/genética , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Tuberculosis/inmunología , Factor de Transcripción ReIB/metabolismo , Factor de Transcripción ReIB/genética , Subunidad p52 de NF-kappa B/metabolismo , Subunidad p52 de NF-kappa B/genética , Análisis de la Célula Individual , Linfocitos T CD8-positivos/inmunología , Linfotoxina-alfa/genética , Linfotoxina-alfa/metabolismo , Adulto Joven , Anciano , Perfilación de la Expresión Génica , Mycobacterium tuberculosis/inmunologíaRESUMEN
ABSTRACT Background: Previous studies have shown an association between polymorphisms of the BAT1-NF-κB inhibitor-like-1 (NFKBIL1)-LTA genomic region and susceptibility to myocardial infarction and acute coronary syndrome (ACS). Objective: The objective of the study was to study the role of three polymorphisms in the BAT1, NFKBIL1, and LTA genes on the susceptibility or protection against ACS; we included a group of cases-controls from Central Mexico. Methods: The BAT1 rs2239527C/G, NFKBIL1 rs2071592T/A, and LTA rs1800683G/A polymorphisms were genotyped using a 5' TaqMan assay in a group of 625 patients with ACS and 617 healthy controls. Results: Under a recessive model, the BAT1 -23C/G (rs2239527) polymorphism showed an association with protection against ACS (odds ratio = 0.56, and p-corrected = 0.019). In contrast, the genotype and allele frequencies of the NFKBIL1 rs2071592T/A and LTA rs1800683G/A polymorphisms were similar between ACS patients and controls and no association was identified. Conclusion: Our data suggest an association between the BAT1 -23C/G polymorphism and protection against ACS in Mexican patients.
Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , ARN Helicasas DEAD-box/genética , Síndrome Coronario Agudo/genética , Infarto del Miocardio/genética , Estudios de Casos y Controles , Linfotoxina-alfa/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Proteínas Adaptadoras Transductoras de Señales/genética , Frecuencia de los Genes , Genotipo , MéxicoRESUMEN
Los desórdenes autoinflamatorios hereditarios constituyen una gama de condiciones heterogéneas que tienen como característica común la aparición de ataques no provocados de inflamación, la cual podría ser sistémica u ocurrir en nichos localizados del organismo. Dentro de estos se encuentran los síndromes hereditarios de fiebre periódica, caracterizados por ataques cortos y recurrentes de fiebre e inflamación localizada grave, que ocurre periódica o irregularmente y que no se explican por las infecciones usuales de la infancia. Forma parte de estas entidades el síndrome periódico asociado al receptor del factor necrosis tumoral, el cual se caracteriza por episodios de fiebre prolongada, mialgias, dolor abdominal, eritema cutáneo migratorio, conjuntivitis o edema periorbitario, con un patrón de herencia autosómico dominante. Lo más importante para el diagnóstico es el análisis genético y su pronóstico está determinado por la aparición de amiloidosis. En 1999, se descubrió su base genética, al identificarse las mutaciones causantes de la enfermedad en el gen que codifica para la superfamilia 1 A del receptor del factor de necrosis tumoral. En años recientes se han logrado avances significativos en el diagnóstico y tratamiento de esta enfermedad gracias a un mejor conocimiento de su patogénesis. En este trabajo se describen los aspectos más relevantes en cuanto a patogénesis, relación de las mutaciones con el fenotipo de la enfermedad, características clínicas y tratamiento(AU)
Hereditary autoinflammatory disorders are a range of heterogeneous conditions that have as a common feature the appearance of unprovoked inflammatory attacks, which may be systemic or occur in localized niches of the body. Among these are hereditary periodic fever syndrome, characterized by short and recurrent attacks of fever and severe localized inflammation, occurring periodically or irregularly and not explained by the usual infections of childhood. Tumor necrosis factor receptor-associated periodic syndrome is part of these entities and is characterized by episodes of prolonged fever, myalgias, abdominal pain, migratory cutaneous erythema, conjunctivitis and/or periorbital edema, with an autosomal dominant inheritance pattern. The most important for the diagnosis is the genetic analysis and its prognosis is determined by the appearance of amyloidosis. In 1999 its genetic basis was discovered by identifying disease-causing mutations in the gene encoding tumor necrosis factor receptor superfamily member 1A. In recent years, significant advances have been achieved in the diagnosis and treatment of this disease, thanks to a better understanding of its pathogenesis. This paper describes the most relevant aspects regarding pathogenesis, relation of mutations with the disease phenotype, clinical characteristics and treatment(AU)
Asunto(s)
Humanos , Masculino , Femenino , Linfotoxina-alfa/genética , Enfermedades Autoinflamatorias Hereditarias , Enfermedades Autoinflamatorias Hereditarias/epidemiología , Convulsiones FebrilesRESUMEN
ABSTRACT Background: Rheumatoid arthritis is a widely prevalent autoimmune disorder with suggested genetic predisposition. Objectives: The aim of this study is to detect the pattern of genetic polymorphism of methylene tetrahydrofolate reductase (MTHFR C677 T and A1298 C), transforming growth factor-β1 (TGF-β1 T869 C) and lymphotoxin-α (LT-α A252G) in patients having rheumatoid arthritis and correlate these patterns to disease activity and serum levels of tumor necrosis factor-alpha (TNF-α), B-Cell Activating Factor (BAFF), and osteopontin. Methods: A total of 194 subjects, 90 controls and 104 patients with rheumatoid arthritis were genotyped for MTHFR C677 T and A1298 C, TGF-β1 T869 C and LT-α A252G polymorphisms using a methodology based on PCR-RFLP. Also serum levels of TNF-α, osteopontin and BAFF were measured by ELISA kits. Results: The CT genotype and T allele of MTHFR C677 T and GG genotype and G allele of LT-α A252G are associated with the risk of RA and with higher levels of the pro-inflammatory cytokine, TNF-α in patients with rheumatoid arthritis. Conclusion: Our findings suggest that there is association between MTHFR C677 T and LT-α A252G genes polymorphisms and increased risk of RA in this sample of Egyptian population.
RESUMO Antecedentes: A artrite reumatoide é uma doença autoimune amplamente prevalente com sugerida predisposição genética. Objetivos: Detectar o padrão de polimorfismo dos genes metilenotetrahidrofolato redutase (MTHFR C677 T e A1298 C), fator de crescimento transformador β1 (TGF-β1 T869 C) e linfotoxina-α (LT-α A252G) em pacientes com artrite reumatoide e correlacionar esses padrões com a atividade da doença e os níveis séricos de fator de necrose tumoral alfa (TNF-α), fator ativador de linfócitos B (BAFF) e osteopontina. Métodos: Foram genotipados 194 indivíduos – 90 controles e 104 com artrite reumatoide – à procura de polimorfismos dos genes MTHFR C677 T e A1298 C, TGF-β1 T869 C e LT-α A252G com uma metodologia baseada na PCR-RFLP. Mensuraram-se também os níveis séricos de TNF-α, osteopontina e BAFF com kits de Elisa. Resultados: O genótipo CT e o alelo T do MTHFR C677 T e o genótipo GG e alelo G do LT-α A252G estão associados ao risco de AR e a níveis mais elevados da citocina pró-inflamatória TNF-α em pacientes com artrite reumatoide. Conclusão Os achados do presente estudo sugerem que há associação entre os polimorfismos dos genes MTHFR C677 T e LT-α A252G e um risco aumentado de AR nessa amostra da população egípcia.
Asunto(s)
Humanos , Artritis Reumatoide/genética , Linfotoxina-alfa/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Factor de Crecimiento Transformador beta1/genética , Artritis Reumatoide/epidemiología , Factores de Crecimiento Transformadores , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , EgiptoRESUMEN
PURPOSE: To investigate the frequencies of polymorphic allele and genotypes for the LT-α gene, position +252 (rs909253), in Brazilian women with preeclampsia.METHODS: This is a case-control study, in which 30 women with preeclampsia, classified according to the criteria of the National High Blood Pressure Education Program, and 115 women in the control group, with at least two healthy pregnancies, were selected. Peripheral blood was collected, and DNA was extracted, followed by genotyping, using specific primers and restriction analysis. The genotypes obtained were AA, AG and GG. Statistical analysis was performed using the χ2association test. The Hardy-Weinberg Equilibrium was tested using the Haploview Program.RESULTS: The results showed no association between genotypes and preeclampsia development (χ2=2.0; p=0.4). When the AG and GG genotypes were grouped according to allele G presence or absence (genotype AA), the data showed that the presence of allele G was not significantly different between cases (women with preeclampsia) and controls (χ2=0.0; p=1.0). The LT-α gene polymorphism, position +252 (rs909253), seems not to be an important candidate for the development of preeclampsia. Other inflammatory genes should be researched, and studies involving gene-environment interactions should be performed, in order to reach a better understanding of the etiology of the preeclampsia.
OBJETIVO: Investigar as frequências do alelo polimórfico e genótipos para o gene da LT-α, posição +252 (rs909253), em mulheres brasileiras com pré-eclâmpsia.MÉTODOS: Trata-se de um estudo caso-controle, em que 30 mulheres com pré-eclâmpsia, classificadas de acordo com os critérios do National High Blood Pressure Education Program, e 115 mulheres do grupo controle, com pelo menos duas gestações saudáveis, foram selecionadas. Amostra de sangue periférico foi colhida, e o DNA foi extraído, seguido pela genotipagem, usando iniciadores específicos e análise de restrição. Os genótipos obtidos foram AA, AG e GG. A análise estatística foi realizada utilizando-se o teste de associação χ2. O Equilíbrio de Hardy-Weinberg foi testado com o auxílio do programa Haploview.RESULTADOS: Os resultados não mostraram associação entre os genótipos e o desenvolvimento de pré-eclâmpsia (χ2=2,0; p=0,4). Quando os genótipos AG e GG foram agrupados de acordo com a presença do alelo G ou ausência (genótipo AA), os dados mostraram que a presença do alelo G não foi significativamente diferente entre casos (mulheres com pré-eclâmpsia) e controles (χ2=0,0; p=1,0). O polimorfismo no gene LT-α, posição +252 (rs909253), parece não ser um importante candidato para o desenvolvimento de pré-eclâmpsia. Outros genes inflamatórios devem ser pesquisados, e estudos envolvendo interações gene-ambiente devem ser realizados para que se possa alcançar um melhor entendimento da etiologia da pré-eclâmpsia.
Asunto(s)
Humanos , Femenino , Embarazo , Adulto , Linfotoxina-alfa/genética , Polimorfismo Genético , Preeclampsia/genética , Brasil , Estudios de Casos y Controles , Predisposición Genética a la EnfermedadRESUMEN
Objectives Oral lichen planus (OLP) is a chronic inflammatory oral mucosal disease. Cytokines play an important role in the pathogenesis and disease progression of OLP. Various reports have implicated cytokine gene polymorphisms in susceptibility to develop some immune mediated conditions including OLP. The purpose of this study was to investigate the association of tumor necrosis factor (TNF)-α, TNF-β and interleukin (IL)-10 gene polymorphisms with the OLP risk. Material and Methods Forty two unrelated patients with OLP and 211 healthy volunteers were genotyped for TNF-α (-308 G/A), TNF-β (+252A/G), IL-10 (-1082G/A), IL-10 (-819C/T), and IL-10 (-592C/A) polymorphisms. Results The frequencies of allele A and genotype GA of TNF-α (-308G/A) were significantly higher while allele G and GG genotypes were lower in OLP patients as compared to the controls (P<0.001). The frequency of GA genotype of TNF-β (+252A/G) was significantly higher in patients than in controls while the AA genotype was completely absent in OLP patients. These results indicated that allele A and genotype GA of TNF-α (-308G/A) as well as the GA genotype of TNF-β (+252A/G) polymorphisms are associated with OLP risk. The frequencies of alleles and genotypes of -1082G/A, -819C/T and -592C/A polymorphisms in IL-10 gene did not differ significantly between OLP patients and controls (P>0.05). However, haplotype ATA extracted from 1082G/A, -819C/T, -592C/A polymorphisms of IL-10 were more prevalent in OLP patients when compared to controls indicating its possible association with OLP susceptibility. Conclusion It is concluded that TNF-α (-308G/A), TNF-β (+252A/G) and IL-10 (-1082G/A, -819C/T and -592C/A) polymorphisms are associated with the susceptibility of OLP, thus giving additional support for the genetic basis of this disease. .
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Adulto Joven , /genética , Liquen Plano Oral/genética , Linfotoxina-alfa/genética , Polimorfismo de Nucleótido Simple/genética , Factor de Necrosis Tumoral alfa/genética , Estudios de Casos y Controles , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad/genética , Liquen Plano Oral/patología , Reacción en Cadena de la Polimerasa , Valores de Referencia , Factores de Riesgo , Arabia Saudita , Factores SexualesRESUMEN
OBJECTIVE: To examine the association of atherogenic and thrombogenic markers and lymphotoxin-alfa gene mutations with the risk of premature coronary disease. METHODS: This cross-sectional, case-control, age-adjusted study was conducted in 336 patients with premature coronary disease (<50 years old) and 189 healthy controls. The control subjects had normal clinical, resting, and exercise stress electrocardiographic assessments. The coronary disease group patients had either angiographically documented disease (>50% luminal reduction) or a previous myocardial infarction. The laboratory data evaluated included thrombogenic factors (fibrinogen, protein C, protein S, and antithrombin III), atherogenic factors (glucose and lipid profiles, lipoprotein(a), and apolipoproteins AI and B), and lymphotoxin-alfa mutations. Genetic variability of lymphotoxin-alfa was determined by polymerase chain reaction analysis. RESULTS: Coronary disease patients exhibited lower concentrations of HDL-cholesterol and higher levels of glucose, lipoprotein(a), and protein S. The frequencies of AA, AG, and GG lymphotoxin-alfa mutation genotypes were 55.0%, 37.6%, and 7.4% for controls and 42.7%, 46.0%, and 11.3% for coronary disease patients (p = 0.02), respectively. Smoking, dyslipidemia, family history, and lipoprotein(a) and lymphotoxin-alfa mutations in men were independent variables associated with coronary disease. The area under the curve (C-statistic) increased from 0.779 to 0.802 (p<0.05) with the inclusion of lipoprotein(a) and lymphotoxin-alfa mutations in the set of conventional risk factors. CONCLUSIONS: The inclusion of lipoprotein(a) and lymphotoxin-alfa mutations in the set of conventional risk factors showed an additive but small increase in the risk prediction of premature coronary disease. .
Asunto(s)
Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aterosclerosis/genética , Enfermedad de la Arteria Coronaria/genética , Linfotoxina-alfa/genética , Aterosclerosis/sangre , Biomarcadores/sangre , Estudios de Casos y Controles , Estudios Transversales , Enfermedad de la Arteria Coronaria/sangre , Predisposición Genética a la Enfermedad , Genotipo , Lipoproteínas/sangre , Lipoproteínas/genética , Mutación/genética , Polimorfismo Genético , Valor Predictivo de las Pruebas , Factores de Riesgo , Curva ROC , Trombosis/sangre , Trombosis/genéticaRESUMEN
The localization and functional characteristics of tumor necrosis factor(TNF) beta gene raise the possibility that it may be involved in the susceptibility to autoimmune thyroid diseases. To investigate whether a TNF beta gene polymorphism is associated with autoimmune thyroiditis, we analyzed the TNF beta gene polymorphism with the restriction enzyme NcoI in 48 Korean patients with atrophic autoimmune thyroiditis [23 were found to be thyrotropin binding inhibitor immunoglobulin(TBII) positive, 25 TBII negative], 52 goitrous autoimmune thyroiditis, and 129 healthy controls. Two TNF beta alleles were identified from the restriction fragment length polymorphism studies of amplified genomic DNA. In atrophic autoimmune thyroiditis patients positive for TBII, 7 of 23 patients were homozygous for the TNF beta * 1 allele, 3 were homozygous for the TNF beta * 2 allele, and 13 were TNF beta * 1/2 heterozygous compared to controls(P = 0.20). Also, there were no associations between the TNF beta gene polymorphism and either TBII-negative atrophic autoimmune thyroiditis or goitrous autoimmune thyroiditis. Of the HLA-class II antigens, the frequency of HLA-DR8 was significantly greater among the 23 Korean patients with TBII-positive atrophic autoimmune thyroiditis compared to control subjects (Pc = 0.003). When the HLA-DR8 positive patients with TBII-positive atrophic autoimmune thyroiditis and controls were analyzed separately, the DR8 positive patients with TBII-positive atrophic autoimmune thyroiditis had more homozygotes for the TNF beta * 1 allele(6/12, 50.0%) and no homozygotes for the TNF beta * 2 allele, as compared to the DR8 negative patients with TBII-positive atrophic autoimmune thyroiditis and DR8 positive controls(P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Humanos , Alelos , Ligamiento Genético , Antígenos HLA-DR/genética , Corea (Geográfico) , Linfotoxina-alfa/genética , Polimorfismo Genético , Receptores de Tirotropina/inmunología , Tiroiditis Autoinmune/genéticaRESUMEN
The purpose of this study was to examine whether there are the associations between TNF alpha and TNF beta gene polymorphisms and the development and progression of Ig A nephropathy (IgAN). A cross-sectional study on TNF alpha and TNF betagene polymorphisms by polymerase chain reaction with restriction fragment length poly-morphisms was performed on 76 patients with primary IgAN confirmed by renal biopsy and 100 healthy controls. The allele with G-->A substitution was designated as TNFA2 for the TNF alpha gene and TNFB2 for the TNF betagene. A patient in whom dialysis treatment was started or whose serum creatinine became double or over during the follow-up duration was designated as a "progressor". The TNFA2/ TNFA2 genotype was more prevalent in the progressor than in the non-pregressor group (20.0 vs 3.3%, p<0.05). Clinical factors such as serum creatinine, systolic and diastolic blood pressure (p<0.001, respectively) were higher and pathologic factor such as Grade IV or V renal lesions was more prevalent (p<0.01) in the progressor than in the non-progressor group. Therefore, TNFA2/TNFA2 genotype may be a risk factor for the progression of IgAN.
Asunto(s)
Adulto , Femenino , Humanos , Masculino , Biopsia , Estudios Transversales , Progresión de la Enfermedad , Genotipo , Glomerulonefritis por IGA/genética , Linfotoxina-alfa/genética , Polimorfismo de Longitud del Fragmento de Restricción , Valor Predictivo de las Pruebas , Pronóstico , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
Introducción y objetivos: El virus del sarampión (VS)aparte de producir complicaciones graves respiratorias,gastrointestinales, encefalitis, ceguera y sordera queacompañan al sarampión y hacen que mate anualmentecerca de un millón de niños en el mundo, es el causantede encefalitis lentas como la Panencefalitis esclerosantesubaguda (PES) o la Encefalitis sarampionosa de cuerposde inclusión (MIBE). Para estas encefalopatías subagudasprogresivas con desmielinización y atrofia cerebral, de curso mortal tras meses a décadas de evolución no se dispone actualmente de tratamiento efectivo. El objetivo de este estudio es la búsqueda de posibles tratamientos para eliminar selectivamente las células infectadas por el virus y así frenar el progreso de la infección y en último término la eliminación del virus del paciente.Métodos: Estudio de sensibilidad a la inducción de apoptosis por la proteína TRAIL (TNF-related-apoptosis inducing ligand) de células humanas en cultivo sin infectar y persistentemente infectadas por VS. Estudio de los mecanismos de inducción de la apoptosis en la línea celular MOLT3, en la que nuestro laboratorio mostró por primera vez que VS puede inducir apoptosis.Resultados: La infección persistente por VS hace que células humanas se hagan marcadamente más sensibles al suicidio celular inducido por TRAIL exógeno. El mecanismo de esta sensibilización podría explicarse por un aumento de la expresión en la superficie celular de las células infectadas de los receptores funcionales para TRAIL, junto con una reducción de la expresión de la proteína antiapoptótica Bcl2 y una estimulación de la quinasa Akt y del factor de transcripción NFkB, lo que provocaría el suicidio de las células infectadas.Conclusiones: Células persistentemente infectadas porVS son más sensibles a la inducción de suicidio por apoptosis mediado por TRAIL que la células no infectadas. El tratamiento con TRAIL al eliminar las células infectadas podría frenar la progresión del virus o incluso eliminarlo en pacientes con encefalitis subagudas causadas por VS como SSPE o MIBE
Introduction: Measles virus (MV) causes acute infectionswith severe respiratory, neurological, deafness, blindness and gastrointestinal complications that today still kill near one million children annually worldwide. The late measles complications Subacute Sclerosing Panencephalitis (SSPE) or Measles Inclusion Bodies Encephalitis (MIBE) show a protracted progressive and fatal course and for them no efficient treatment is currently available. This work aims to find a way to selectively destroy the infected cells, and doing so limit the progression of VS through the infectedbrain and eventually to eliminate the virus from the patient with SSPE or MIBE.Materials and Methods: Sensitivity to apoptosis induced by exogenous recombinant TRAIL was determined in steady-state MV persistently infected human cell line MOLT3 versus uninfected cells, by chromatin condensation, TUNEL, and caspases activation assays. Expression of TRAIL functional receptors (TRAIL-R1 y TRAIL-R2) and decoy receptors (TRAIL-R3 and TRAIL-R4) was determined by flow cytometry and western- blots. mRNAs of pro- and antiapopoptotic factors were quantitated by RT-PCR and RNAse protection assays. Activation of NFkB by EMSA and supershift electrophoretic assays.Results: MV persistently infected MOLT3 cells becamehighly sensitive to apoptosis induced by exogenous TRAIL.This sensitization could be explained by the observed MV infection up-regulation in the infected cells of the expression of TRAIL functional receptors TRAIL-R1 and TRAIL-R2 and down-regulation of the expression of antiapoptotic factor Bcl2 and activation of the protein-kinase Akt and NF-kB that would provoke the suicide of the infected cells.Conclusions: The high sensitization to induced apoptosisby exogenous TRAIL observed in MV persistently infectedcells suggest that treatment with recombinant TRAIL couldselectively eliminate MV infected cells in the CNS of patients and it could be possible to exploit this agent for the treatment of SSPE or MIBE encephalopaties (AU)