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1.
Rev. argent. reumatol ; 29(3): 6-10, set. 2018. tab
Artículo en Español | LILACS | ID: biblio-977290

RESUMEN

Objetivos: Estimar el efecto de los antimaláricos (AM) sobre los diferentes dominios del índice de daño SLICC (SDI). Métodos: Se estudiaron pacientes con diagnóstico clínico reciente (≤2 años) de lupus eritematoso sistémico (LES) de la cohorte GLADEL. Variable de estudio: aumento en los dominios del SDI desde el ingreso a la cohorte. Variables independientes: características sociodemográficas, clínicas, laboratorio y tratamientos. El efecto de los AM, como variable dependiente del tiempo, sobre los dominios más frecuentes del SDI (ajustado por factores de confusión) fue examinado con un modelo de regresión de Cox multivariado. Resultados: De 1466 pacientes estudiados, 1049 (72%) recibieron AM con un tiempo medio de exposición de 30 meses (Q1-Q3: 11-57) y 665 pacientes (45%) presentaron daño durante un seguimiento medio de 24 meses (Q1-Q3: 8-55); 301 eventos fueron cutáneos, 208 renales, 149 neuropsiquiátricos, 98 musculoesqueléticos, 88 cardiovasculares y 230 otros. Después de ajustar por factores de confusión, el uso de AM se asoció a un menor riesgo de daño renal (HR 0,652; IC 95%: 0,472-0,901) y en el límite de la significancia estadística (HR 0,701, IC 95%: 0,481-1,024) para el dominio neuropsiquiátrico. Conclusión: En GLADEL, el uso de AM se asoció independientemente a un menor riesgo de daño acumulado renal.


Objective: To assess the effects of antimalarials (AM) over the items of the SLICC Damage Index (SDI). Methods: Patients with recent (≤2 years) diagnosis of systemic lupus erythematosus (SLE) from the GLADEL cohort were studied. End-point: increase in items SDI since cohort entry. Independent variables (socio-demographic, clinical, laboratory and treatment) were included. The effect of AM as a time dependent variable on most frequent SDI items (adjusting for potential confounders) was examined with a multivariable Cox regression model. Results: Of the 1466 patients included in this analysis, 1049 (72%) received AM with a median exposure time of 30 months (Q1-Q3: 11-57). Damage occurred in 665 (45%) patients during a median follow-up time of 24 months (Q1-Q3: 8-55). There were 301 integument, 208 renal, 149 neuropsychiatric, 98 musculoskeletal, 88 cardiovascular and 230 others less frequently represented damages. After adjusting for potential confounders at any time during follow-up, a lower risk of renal damage (HR 0.652; 95% CI: 0.472-0.901) and borderline for neuropsychiatric damage (HR 0.701, 95% CI: 0.481-1.024) was found. Conclusion: In the GLADEL cohort, after adjustment for possible confounding factors, AM were independently associated with a reduced risk of renal damage accrual.


Asunto(s)
Lupus Eritematoso Sistémico , Antimaláricos
3.
Clin Immunol ; 148(2): 237-45, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23773922

RESUMEN

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder that is characterized by the over production of auto-antibodies against nuclear components. Thus, SLE patients have increased morbidity and, mortality compared to healthy individuals. Available therapies are not curative and are associated with unwanted adverse effects. During the last few years, important advances in immunology research have provided rheumatologists with new tools for designing novel therapies for treating autoimmunity. However, the complex nature of SLE has played a conflicting role, hindering breakthroughs in therapeutic development. Nonetheless, new advances about SLE pathogenesis could open a fruitful line of research. Dendritic cells (DCs) have been established as essential players in the mechanisms underlying SLE, making them attractive therapeutic targets for fine-tuning the immune system. In this review, we discuss the recent advances made in revealing the mechanisms of SLE pathogenesis, with a focus on the use of DCs as a target for therapy development.


Asunto(s)
Células Dendríticas/fisiología , Tolerancia Inmunológica/inmunología , Lupus Eritematoso Sistémico/terapia , Humanos , Tolerancia Inmunológica/fisiología , Inmunidad Innata
4.
Immunology ; 140(1): 123-32, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23691924

RESUMEN

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple alterations affecting the normal function of immune cells, such as lymphocytes, dendritic cells (DCs) and monocytes. Although the understanding of autoimmunity has significantly increased, the breakthrough in effective therapies has been modest, making necessary the development of new therapeutic strategies. Here we propose that a new potential target for therapy is haem oxygenase-1 (HO-1), an enzyme that catalyses the degradation of the haem group into biliverdin, carbon monoxide (CO) and Fe(2+) . These products exhibit immunosuppressive and anti-inflammatory effects, which can contribute to improving tolerance during organ transplantation. Because HO-1 is highly expressed by immune cells involved in SLE pathogenesis, such as monocytes and DCs, we evaluated whether induction of HO-1 expression or the administration of CO could ameliorate disease in the FcγRIIb knockout (KO) mouse model for SLE. We found that CO administration decreased the expansion of CD11b(+) cells, prevented the decline of regulatory T cells and reduced anti-histone antibodies observed in untreated FcγRIIb KO mice. Furthermore, CO-treated animals and HO-1 induction showed less kidney damage compared with untreated mice. These data suggest that HO-1 modulation and CO administration can ameliorate autoimmunity and prevent the lupus symptoms shown by FcγRIIb KO mice, highlighting HO-1 as a potential new target for autoimmune therapy.


Asunto(s)
Monóxido de Carbono/administración & dosificación , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/terapia , Animales , Autoinmunidad/efectos de los fármacos , Antígeno CD11b/metabolismo , Modelos Animales de Enfermedad , Inducción Enzimática/efectos de los fármacos , Femenino , Hemo-Oxigenasa 1/biosíntesis , Riñón/efectos de los fármacos , Riñón/enzimología , Riñón/patología , Lupus Eritematoso Sistémico/enzimología , Masculino , Proteínas de la Membrana/biosíntesis , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de IgG/deficiencia , Receptores de IgG/genética , Bazo/inmunología , Bazo/patología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología
5.
Immunology ; 136(4): 414-24, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22587389

RESUMEN

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple functional alterations affecting immune cells, such as B cells, T cells, dendritic cells (DCs) and monocytes. During SLE, the immunogenicity of monocytes and DCs is significantly up-regulated, promoting the activation of self-reactive T cells. Accordingly, it is important to understand the contribution of these cells to the pathogenesis of SLE and the mechanisms responsible for their altered functionality during disease. One of the key enzymes that control monocyte and DC function is haem oxygenase-1 (HO-1), which catalyses the degradation of the haem group into biliverdin, carbon monoxide and free iron. These products possess immunosuppressive and anti-inflammatory capacities. The main goal of this work was to determine HO-1 expression in monocytes and DCs from patients with SLE and healthy controls. Hence, peripheral blood mononuclear cells were obtained from 43 patients with SLE and 30 healthy controls. CD14(+) monocytes and CD4(+) T cells were sorted by FACS and HO-1 expression was measured by RT-PCR. In addition, HO-1 protein expression was determined by FACS. HO-1 levels in monocytes were significantly reduced in patients with SLE compared with healthy controls. These results were confirmed by flow cytometry. No differences were observed in other cell types, such as DCs or CD4(+) T cells, although decreased MHC-II levels were observed in DCs from patients with SLE. In conclusion, we found a significant decrease in HO-1 expression, specifically in monocytes from patients with SLE, suggesting that an imbalance of monocyte function could be partly the result of a decrease in HO-1 expression.


Asunto(s)
Células Dendríticas/enzimología , Hemo-Oxigenasa 1/metabolismo , Lupus Eritematoso Sistémico/enzimología , Lupus Eritematoso Sistémico/inmunología , Monocitos/enzimología , Adulto , Animales , Artritis Reumatoide/inmunología , Artritis Reumatoide/patología , Linfocitos T CD4-Positivos/enzimología , Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Femenino , Humanos , Receptores de Lipopolisacáridos/biosíntesis , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Monocitos/inmunología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de IgG/genética , Receptores de IgG/inmunología , Adulto Joven
6.
Curr Gene Ther ; 11(6): 544-53, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22023471

RESUMEN

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease characterized by an excessive production of auto-antibodies against double-stranded DNA, nucleosomes, ribonucleoproteins and other nuclear components. Accumulation of self-reactive antibodies leads to immune complex deposition in blood vessels, activation of macrophages and complement, inflammation and subsequent tissue damage in several organs, such as the heart, kidneys, lungs and central nervous system. Although significant progress has been made in the past 30 years of research, no effective specific treatments are currently available. The course of this disease remains unpredictable and patients diagnosed with SLE face long-term treatments with the subsequent economic, social and health burden. From the immunological perspective, SLE is a genetic- and environment-controlled disease that involves almost every constituent of the immune system, including both innate and adaptive immunity. Therefore, several immune cell types and molecules could be susceptible for intervention and modulation to develop more effective and specific treatments. More importantly, such therapies are likely not to induce complete immunosuppression and show reduced side effects on patients. In this article we discuss recent work in the field of SLE pathogenesis with a focus on data that provide clues for therapy design and new treatments.


Asunto(s)
Células Dendríticas/inmunología , Lupus Eritematoso Sistémico/terapia , Linfocitos T/inmunología , Autoinmunidad , Linfocitos B/inmunología , Humanos , Lupus Eritematoso Sistémico/inmunología
7.
Rev Med Chil ; 138(6): 746-51, 2010 Jun.
Artículo en Español | MEDLINE | ID: mdl-20919486

RESUMEN

Behçet's disease (BD) is a systemic inflammatory vascular disease with several clinical manifestations and geographical differences in disease expression. In Middle Eastern countries it is one of the most common causes of cerebral venous thrombosis. We report a 29-year-old female admitted for acute headache and vomiting. A magnetic resonance image showed a large thrombosis of sagital and transverse sinuses. She developed oral and genital ulcers a week later. Ophthalmologic examination revealed left anterior uveitis and ipsilateral papilledema. Multiple studies ruled out a hypercoagulability syndrome. The patient used oral contraceptives. Anticoagulant therapy was prescribed. A biopsy of a genital ulcer demonstrated diffuse lymphocytic infiltration with vasculitis. After treatment with topical and systemic corticoids, her condition improved. Venous sinus thrombosis followed by oral and genital ulcers is an unusual presentation of Behçet's disease.


Asunto(s)
Síndrome de Behçet/complicaciones , Trombosis de los Senos Intracraneales/etiología , Adulto , Femenino , Humanos , Trombosis de los Senos Intracraneales/patología
8.
Rev Med Chil ; 138(3): 334-7, 2010 Mar.
Artículo en Español | MEDLINE | ID: mdl-20556337

RESUMEN

The classical manifestations of Behçet disease are mouth ana genital ulcers, cutaneous lesions ana ocular involvement. The central nervous system is affected in 5 to 59% of the cases, usually in the form of meningoencephalitis or sinus venous thrombosis. We report a 17-year-old femóle presenting with a two weeks history of progressive headache, nausea and blurred vision. An initial magnetic resonance was normal. Fifteen days later she was admitted to the hospital due to progression of visual impairment. She gave a history of oral ulcers and arthralgias. A new magnetic resonance was normal. A lumbar puncture showed a cerebrospinal fluid with a protein concentration of 14 mg/dl, a glucose concentration of 64 mg/dl, 20 fresh red blood cells and a pressure of 26 cm H(2)0. The diagnosis of a pseudotumor cerebri, secondary to Behçet disease was raised and the patient was treated with colchicine and acetazolamide. The evolution was torpid and an anterior uveitis was also found. After discharge, she continued with oral and genital ulcers and was treated with infliximab. Despite treatment, headache persists.


Asunto(s)
Síndrome de Behçet/complicaciones , Seudotumor Cerebral/etiología , Acetazolamida/uso terapéutico , Adolescente , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/tratamiento farmacológico , Colchicina/uso terapéutico , Femenino , Humanos , Seudotumor Cerebral/diagnóstico , Seudotumor Cerebral/tratamiento farmacológico
9.
Rev. méd. Chile ; 138(6): 746-751, jun. 2010. ilus, tab
Artículo en Español | LILACS | ID: lil-567571

RESUMEN

Behçet’s disease (BD) is a systemic inflammatory vascular disease with several clinical manifestations and geographical differences in disease expression. In Middle Eastern countries it is one of the most common causes of cerebral venous thrombosis. We report a 29-year-old female admitted for acute headache and vomiting. A magnetic resonance image showed a large thrombosis of sagital and transverse sinuses. She developed oral and genital ulcers a week later. Ophthalmologic examination revealed left anterior uveitis and ipsilateral papilledema. Multiple studies ruled out a hypercoagulability syndrome. The patient used oral contraceptives. Anticoagulant therapy was prescribed. A biopsy of a genital ulcer demonstrated diffuse lymphocytic infiltration with vasculitis. After treatment with topical and systemic corticoids, her condition improved. Venous sinus thrombosis followed by oral and genital ulcers is an unusual presentation of Behçet’s disease.


Asunto(s)
Adulto , Femenino , Humanos , Síndrome de Behçet/complicaciones , Trombosis de los Senos Intracraneales/etiología , Trombosis de los Senos Intracraneales/patología
10.
Rev. méd. Chile ; 138(3): 334-337, mar. 2010. ilus, tab
Artículo en Español | LILACS | ID: lil-548169

RESUMEN

The classical manifestations of Behçet disease are mouth ana genital ulcers, cutaneous lesions ana ocular involvement. The central nervous system is affected in 5 to 59 percent of the cases, usually in the form of meningoencephalitis or sinus venous thrombosis. We report a 17-year-old femóle presenting with a two weeks history of progressive headache, nausea and blurred vision. An initial magnetic resonance was normal. Fifteen days later she was admitted to the hospital due to progression of visual impairment. Shegave a history of oral ulcers and arthralgias. A new magnetic resonance was normal. A lumbar puncture showed a cerebrospinal fluid with a protein concentration of 14 mg/dl, aglucose concentration of 64 mg/dl, 20fresh red blood cells and a pressure of 26 cm H(2)0. The diagnosis of a pseudotumor cerebri, secondary to Behçet disease was raised and the patient was treated with colchicine and acetazolamide. The evolution was torpid and an anterior uveitis was alsofound. After discharge, she continued with oral and genital ulcers and was treated with infliximab. Despite treatment, headache persists.


Asunto(s)
Adolescente , Femenino , Humanos , Síndrome de Behçet/complicaciones , Seudotumor Cerebral/etiología , Acetazolamida/uso terapéutico , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/tratamiento farmacológico , Colchicina/uso terapéutico , Seudotumor Cerebral/diagnóstico , Seudotumor Cerebral/tratamiento farmacológico
11.
Immunology ; 128(3): 334-41, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20067533

RESUMEN

Dendritic cells (DCs) play a pivotal role in the interface between immunity and maintenance of peripheral tolerance. The capture of immunoglobulin G (IgG)-containing immune complexes (ICs) by low-affinity Fc gamma receptors (Fc gammaRs) expressed on DCs may influence the immunogenicity/tolerogenicity of these cells, depending on the activating/inhibitory potential of Fc gammaRs. Because of the key role that low-affinity Fc gammaRs play in determining the magnitude of the response in IC-driven inflammation, these receptors are likely to play a role in autoimmune diseases, such as systemic lupus erythematosus (SLE). To evaluate if an altered expression of costimulatory molecules and/or Fc gammaRs could account for disease severity, we evaluated the expression of these molecules on immature and mature DCs derived from peripheral blood monocytes of SLE patients and healthy donors. Our results show an increased expression of the costimulatory molecules CD40 and CD86. Furthermore, the ratio of CD86/CD80 is higher in SLE patients compared with healthy donors. Conversely, while the expression of activating Fc gammaRs was higher on DCs from SLE patients, expression of inhibitory Fc gammaRs was lower, compared with DCs obtained from healthy donors. As a result, the activating to inhibitory Fc gammaR ratio was significantly higher in DCs from SLE patients. The altered ratio of activating/inhibitory Fc gammaRs on mature DCs showed a significant correlation with the activity of SLE, as determined by the SLE Disease Activity Index (SLEDAI) score. We postulate that the increased ratio of activating/inhibitory Fc gammaRs expressed on DCs from SLE patients can contribute to the failure of peripheral tolerance in the IC-mediated phase of autoimmune pathogenesis.


Asunto(s)
Antígenos CD/biosíntesis , Células Dendríticas/metabolismo , Lupus Eritematoso Sistémico/inmunología , Receptores de IgG/biosíntesis , Adulto , Antígenos CD/genética , Antígenos CD/inmunología , Diferenciación Celular , Células Dendríticas/inmunología , Células Dendríticas/patología , Progresión de la Enfermedad , Femenino , Humanos , Inmunomodulación , Lupus Eritematoso Sistémico/fisiopatología , Masculino , Persona de Mediana Edad , Receptores de IgG/genética , Receptores de IgG/inmunología , Autotolerancia , Índice de Severidad de la Enfermedad
12.
Immunology ; 128(1 Suppl): e306-14, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19016912

RESUMEN

Autoimmune diseases, such as systemic lupus erythematosus (SLE), result from deficiencies in self-antigen tolerance processes, which require regulated dendritic cell (DC) function. In this study we evaluated the phenotype of DCs during the onset of SLE in a mouse model, in which deletion of the inhibitory receptor FcgammaRIIb leads to the production of anti-nuclear antibodies and glomerulonephritis. Splenic DCs from FcgammaRIIb-deficient mice suffering from SLE showed increased expression of co-stimulatory molecules. Furthermore, diseased mice showed an altered function of the nuclear factor-kappaB (NF-kappaB) transcription factor, which is involved in DC maturation. Compared with healthy animals, expression of the inhibitory molecule IkappaB-alpha was significantly decreased in mice suffering from SLE. Consistently, pharmacological inhibition of NF-kappaB activity in FcgammaRIIb-deficient mice led to reduced susceptibility to SLE and prevented symptoms, such as anti-nuclear antibodies and kidney damage. Our data suggest that the occurrence of SLE is significantly influenced by alterations of NF-kappaB function, which can be considered as a new therapeutic target for this disease.


Asunto(s)
Células Dendríticas/inmunología , Glomerulonefritis/inmunología , Lupus Eritematoso Sistémico/inmunología , FN-kappa B/inmunología , Receptores de IgG/inmunología , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Diterpenos/administración & dosificación , Diterpenos/farmacología , Femenino , Glomerulonefritis/metabolismo , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacología , Proteínas I-kappa B/agonistas , Proteínas I-kappa B/inmunología , Proteínas I-kappa B/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Receptores de IgG/genética , Receptores de IgG/metabolismo , Rosiglitazona , Tiazolidinedionas/administración & dosificación , Tiazolidinedionas/farmacología
13.
Eur J Immunol ; 38(8): 2241-50, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18604868

RESUMEN

The molecular bases responsible for the loss of T cell tolerance to myelin antigens leading to the onset of multiple sclerosis remain obscure. It has been shown that balanced signaling through activating and inhibitory receptors is critical for the maintenance of tolerance to self antigens in autoimmune disorders. However, although FcgammaR have been shown to influence experimental autoimmune encephalomyelitis (EAE) development, their role during pathogenesis remains controversial. Here we have evaluated whether relative expression of activating (FcgammaRIII) and inhibitory (FcgammaRIIb) FcgammaR can modulate myelin-specific T cell response, as well as the susceptibility to develop EAE in mice. While FcgammaRIIb(-/-) mice showed a significant increase in EAE severity, an FcgammaRIII deficiency protected mice from disease. In addition, FcgammaRIIb(-/-) mice showed enhanced activation of myelin-specific effector T cells, which were significantly more effective at causing EAE in adoptive transfer experiments than were T cells from wild-type mice. In contrast, FcgammaRIII(-/-) mice showed a significantly reduced activation of myelin-specific T cells and these cells failed to adoptively transfer EAE. Consistently, increased expansion of regulatory T cells (Treg) during EAE was observed only for FcgammaRIII(-/-) mice, which were able to suppress disease when adoptively transferred to recipient mice. These findings suggest that the balance between activating and inhibitory FcgammaR signaling can contribute to the maintenance of T cell tolerance to myelin antigens and modulate EAE progression.


Asunto(s)
Encefalomielitis Autoinmune Experimental/etiología , Receptores de IgG/fisiología , Linfocitos T/inmunología , Traslado Adoptivo , Animales , Autoinmunidad , Células Dendríticas/fisiología , Femenino , Ratones , Ratones Endogámicos C57BL , Proteínas de la Mielina , Glicoproteína Asociada a Mielina/inmunología , Glicoproteína Mielina-Oligodendrócito , Linfocitos T Reguladores/fisiología
14.
J Exp Med ; 204(13): 3221-34, 2007 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-18056288

RESUMEN

The interesting observation was made 20 years ago that psychotic manifestations in patients with systemic lupus erythematosus are associated with the production of antiribosomal-P protein (anti-P) autoantibodies. Since then, the pathogenic role of anti-P antibodies has attracted considerable attention, giving rise to long-term controversies as evidence has either contradicted or confirmed their clinical association with lupus psychosis. Furthermore, a plausible mechanism supporting an anti-P-mediated neuronal dysfunction is still lacking. We show that anti-P antibodies recognize a new integral membrane protein of the neuronal cell surface. In the brain, this neuronal surface P antigen (NSPA) is preferentially distributed in areas involved in memory, cognition, and emotion. When added to brain cellular cultures, anti-P antibodies caused a rapid and sustained increase in calcium influx in neurons, resulting in apoptotic cell death. In contrast, astrocytes, which do not express NSPA, were not affected. Injection of anti-P antibodies into the brain of living rats also triggered neuronal death by apoptosis. These results demonstrate a neuropathogenic potential of anti-P antibodies and contribute a mechanistic basis for psychiatric lupus. They also provide a molecular target for future exploration of this and other psychiatric diseases.


Asunto(s)
Apoptosis , Autoanticuerpos/química , Calcio/química , Membrana Celular/metabolismo , Vasculitis por Lupus del Sistema Nervioso Central/inmunología , Neuronas/metabolismo , Proteínas/química , Animales , Encéfalo/metabolismo , Calcio/metabolismo , Sistema Nervioso Central/metabolismo , Epítopos/química , Humanos , Vasculitis por Lupus del Sistema Nervioso Central/metabolismo , Modelos Biológicos , Péptidos/química , Ratas , Ribosomas/metabolismo , Sinaptosomas/metabolismo
15.
J Pharmacol Exp Ther ; 318(1): 59-67, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16597709

RESUMEN

Autoimmune disorders develop as a result of deregulated immune responses that target self-antigens and cause destruction of healthy host tissues. Because dendritic cells (DCs) play an important role in the maintenance of peripheral immune tolerance, we are interested in identifying means of enhancing their therapeutic potential in autoimmune diseases. It is thought that during steady state, DCs are able to anergize potentially harmful T cells bearing T cell receptors that recognize self-peptide-major histocompatibility complexes. The tolerogenic capacity of DCs requires an immature phenotype, which is characterized by a reduced expression of costimulatory molecules. On the contrary, activation of antigen-specific naive T cells is enhanced by DC maturation, a process that involves expression of genes controlled by the transcription factor nuclear factor (NF)-kappaB. We evaluated the capacity of drugs that inhibit NF-kappaB to enhance the tolerogenic properties of immature DCs in the experimental autoimmune encephalomyelitis (EAE) model. We show that andrographolide, a bicyclic diterpenoid lactone, and rosiglitazone, a peroxisome proliferator-activated receptor gamma agonist, were able to interfere with NF-kappaB activation in murine DCs. As a result, treated DCs showed impaired maturation and a reduced capacity to activate antigen-specific T cells. Furthermore, NF-kappaB-blocked DCs had an enhanced tolerogenic capacity and were able to prevent EAE development in mice. The tolerogenic feature was specific for myelin antigens and involved the expansion of regulatory T cells. These data suggest that NF-kappaB blockade is a potential pharmacological approach that can be used to enhance the tolerogenic ability of immature DCs to prevent detrimental autoimmune responses.


Asunto(s)
Antígenos/inmunología , Células Dendríticas/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , FN-kappa B/antagonistas & inhibidores , FN-kappa B/inmunología , Animales , Femenino , Tolerancia Inmunológica/inmunología , Ratones , Ratones Endogámicos C57BL , Linfocitos T/inmunología
16.
Rev Med Chil ; 134(2): 159-66, 2006 Feb.
Artículo en Español | MEDLINE | ID: mdl-16554922

RESUMEN

BACKGROUND: The family of lectins known as galectins (galectins 1-14) are involved in the regulation of the immune system and in oncogenesis. During a search for antigens recognized by antibodies produced by a patient with systemic lupus erythematosus (SLE) we found reactivity against galectin-8, for which autoantibodies have not been previously described. AIM: To determine the frequency of autoantibodies against galectin-8 in lupus patients compared with healthy controls. PATIENTS AND METHODS: Galectin-8 was purified from a bacterial expression system and used in immunoblot assays as antigen to screen the sera of 55 SLE patients and matched controls. Disease activity was evaluated using the Mexican Modification of the Systemic Lupus Erythematosus Disease Activity Index (MEX-SLEDAI). RESULTS: Reactivity against galectin-8 was detected in 30% of SLE patients, compared to 7% of controls (p=0.003). We could not detect any particular SLE manifestation associated to the presence of these autoantibodies. CONCLUSIONS: This is the first description of autoantibodies against galectin-8. Its higher frequency in patients with SLE suggests a pathogenic role. Further studies are needed to determine their clinical relevance.


Asunto(s)
Autoanticuerpos/sangre , Autoantígenos/sangre , Galectinas/inmunología , Lupus Eritematoso Sistémico/inmunología , Adolescente , Adulto , Anciano , Análisis de Varianza , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Galectinas/biosíntesis , Humanos , Immunoblotting , Masculino , Persona de Mediana Edad
17.
Rev. méd. Chile ; 134(2): 159-166, feb. 2006. ilus, graf
Artículo en Español | LILACS | ID: lil-425963

RESUMEN

Background: The family of lectins known as galectins (galectins 1-14) are involved in the regulation of the immune system and in oncogenesis. During a search for antigens recognized by antibodies produced by a patient with systemic lupus erythematosus (SLE) we found reactivity against galectin-8, for which autoantibodies have not been previously described. Aim: To determine the frequency of autoantibodies against galectin-8 in lupus patients compared with healthy controls. Patients and Methods: Galectin-8 was purified from a bacterial expression system and used in immunoblot assays as antigen to screen the sera of 55 SLE patients and matched controls. Disease activity was evaluated using the Mexican Modification of the Systemic Lupus Erythematosus Disease Activity Index (MEX-SLEDAI). Results: Reactivity against galectin-8 was detected in 30% of SLE patients, compared to 7% of controls (p=0.003). We could not detect any particular SLE manifestation associated to the presence of these autoantibodies. Conclusions: This is the first description of autoantibodies against galectin-8. Its higher frequency in patients with SLE suggests a pathogenic role. Further studies are needed to determine their clinical relevance.


Asunto(s)
Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Autoanticuerpos/sangre , Autoantígenos/sangre , Galectinas/inmunología , Lupus Eritematoso Sistémico/inmunología , Análisis de Varianza , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Galectinas/biosíntesis , Immunoblotting
18.
Int Immunol ; 18(2): 259-67, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16373365

RESUMEN

Immune surveillance depends on still poorly understood lymphocyte-endothelium interactions required for lymphocyte transendothelial migration into secondary lymphoid organs. The nuclear factor kappaB (NF-kappaB) regulatory system and its inhibitory IkappaB proteins control the inducible expression of adhesion molecules, cytokines and chemokines involved in endothelial activation and lymphocyte transmigration. Here we present results showing the activation of this system in response to the interaction of high endothelial cells from human tonsils (HUTEC) with human B and T lymphoid cell lines and primary tonsillar lymphocytes. Western blot and electrophoretic mobility shift assays show that adhesion of different lymphoid cells induce varying levels of NF-kappaB activation in HUTEC, with Daudi cells, tonsil-derived B cell line 10 (TBCL-10) and primary tonsillar B lymphocytes causing the strongest activation. The main NF-kappaB protein complexes translocated to the nucleus were p65/p50 and p50/p50. Results from reverse transcription-PCR and flow cytometry analysis of HUTEC indicate that the interaction with Daudi cells induce an increased expression of IL-6 and IL-8 mRNA and cell-surface expression of intercellular adhesion molecule-1, all of which were prevented by sodium salicylate, an inhibitor of NF-kappaB activation. Transwell experiments show that NF-kappaB activation and the response of HUTEC to the interaction of Daudi cells does not depend on direct cell-cell contact but rather on the production of soluble factors that require the presence of both cell types. These results suggest that lymphocytes and high endothelium establish a cross talk leading to NF-kappaB-mediated expression of cytokines and adhesion molecules, inducing endothelial cell activation.


Asunto(s)
Linfocitos B/fisiología , Células Endoteliales/metabolismo , FN-kappa B/metabolismo , Tonsila Palatina/citología , Técnicas de Cocultivo , Citocinas/genética , Humanos , Molécula 1 de Adhesión Intercelular/biosíntesis , Activación de Linfocitos , ARN Mensajero/metabolismo , Células Tumorales Cultivadas
19.
Exp Cell Res ; 312(4): 374-86, 2006 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-16368432

RESUMEN

Integrin-mediated encounters of T cells with extracellular cues lead these cells to adhere to a variety of substrates and acquire a spread phenotype needed for their tissue incursions. We studied the effects of galectin-8 (Gal-8), a beta-galactoside binding lectin, on Jurkat T cells. Immobilized Gal-8 bound alpha1beta1, alpha3beta1 and alpha5beta1 but not alpha2beta1 and alpha4beta1 and adhered these cells with similar kinetics to immobilized fibronectin (FN). Function-blocking experiments with monoclonal anti-integrin antibodies suggested that alpha5beta1 is the main mediator of cell adhesion to this lectin. Gal-8, but not FN, induced extensive cell spreading frequently leading to a polarized phenotype characterized by an asymmetric lamellipodial protrusion. These morphological changes involved actin cytoskeletal rearrangements controlled by PI3K, Rac-1 and ERK1/2 activity. Gal-8-induced Rac-1 activation and binding to alpha1 and alpha5 integrins have not been described in any other cellular system. Strikingly, Gal-8 was also a strong stimulus on Jurkat cells in suspension, triggering ERK1/2 activation that in most adherent cells is instead dependent on cell attachment. In addition, we found that patients with systemic lupus erythematosus (SLE), a prototypic autoimmune disorder, produce Gal-8 autoantibodies that impede both its binding to integrins and cell adhesion. These are the first function-blocking autoantibodies reported for a member of the galectin family. These results indicate that Gal-8 constitutes a novel extracellular stimulus for T cells, able to bind specific beta1 integrins and to trigger signaling pathways conducive to cell spreading. Gal-8 could modulate a wide range of T cell-driven immune processes that eventually become altered in autoimmune disorders.


Asunto(s)
Galectinas/metabolismo , Integrina beta1/metabolismo , Androstadienos/farmacología , Anticuerpos Monoclonales/farmacología , Autoanticuerpos/farmacología , Adhesión Celular/efectos de los fármacos , Adhesión Celular/fisiología , Forma de la Célula/efectos de los fármacos , Extensiones de la Superficie Celular/efectos de los fármacos , Extensiones de la Superficie Celular/fisiología , Citocalasina D/farmacología , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Fibronectinas/metabolismo , Fibronectinas/farmacología , Flavonoides/farmacología , Galectinas/antagonistas & inhibidores , Galectinas/farmacología , Humanos , Integrina beta1/inmunología , Células Jurkat , Leucemia de Células T/metabolismo , Leucemia de Células T/patología , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Lupus Eritematoso Sistémico/inmunología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Unión Proteica/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Tiogalactósidos/farmacología , Transfección , Wortmanina , Proteína de Unión al GTP rac1/genética , Proteína de Unión al GTP rac1/metabolismo
20.
Rev Med Chil ; 133(3): 273-8, 2005 Mar.
Artículo en Español | MEDLINE | ID: mdl-15880180

RESUMEN

BACKGROUND: Systemic vasculitis are a group of heterogeneous diseases characterized by inflammation and necrosis of blood vessel walls. The etiology is not known, but geographic and environmental factors are implicated. AIM: To describe the clinical features of microscopic polyangiitis (MPA) and Wegener's granulomatosis (WG) in a Chilean cohort of patients. PATIENTS AND METHODS: Retrospective review of the medical records of 123 patients with the diagnosis of systemic vasculitis (65 MPA and 58 WG), seen from 1990 to 2001. The diagnosis were made based on the American College of Rheumatology and Chapel Hill criteria. RESULTS: The mean follow-up for MPA was 15 months (1-120) and for WG, 20 months (1-120). The median age (years) at diagnosis for MPA was 61 (19-82) and WG 50 (20-82). Gender distribution was similar in both groups (male: 68% and 57% respectively). The main clinical features in the MPA group were renal involvement (68%), peripheral nervous system involvement (57%), pulmonary hemorrhage (28%), and skin disease (32%). In the WG group were alveolar hemorrhage (62%), renal involvement (78%), paranasal sinus involvement (57%), and ocular disease (26%). In both, creatinine levels above 2.0 mg/dl were associated with a higher mortality (p< 0.01). ANCA by immunofluorescence was performed in 56 MPA patients (75% had pANCA, 4% had cANCA and 21% were ANCA negative) and in 55 WG patients (17% had pANCA, 79% had cANCA and 4% were ANCA negative). Global mortality was 18% and 17% respectively, and the most common causes of death were infections. CONCLUSIONS: The clinical features of our patients are similar to other published data. In our WG and MPA patients the main predictor for death was a serum creatinine above 2 mg/dl.


Asunto(s)
Granulomatosis con Poliangitis , Poliarteritis Nudosa , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Anticitoplasma de Neutrófilos/análisis , Chile , Creatinina/sangre , Femenino , Técnica del Anticuerpo Fluorescente Directa , Estudios de Seguimiento , Granulomatosis con Poliangitis/complicaciones , Granulomatosis con Poliangitis/inmunología , Granulomatosis con Poliangitis/patología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Poliarteritis Nudosa/complicaciones , Poliarteritis Nudosa/inmunología , Poliarteritis Nudosa/patología , Estudios Retrospectivos , Distribución por Sexo
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