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1.
Cell ; 133(2): 235-49, 2008 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-18423196

RESUMEN

Multiple lung pathogens such as chemical agents, H5N1 avian flu, or SARS cause high lethality due to acute respiratory distress syndrome. Here we report that Toll-like receptor 4 (TLR4) mutant mice display natural resistance to acid-induced acute lung injury (ALI). We show that TLR4-TRIF-TRAF6 signaling is a key disease pathway that controls the severity of ALI. The oxidized phospholipid (OxPL) OxPAPC was identified to induce lung injury and cytokine production by lung macrophages via TLR4-TRIF. We observed OxPL production in the lungs of humans and animals infected with SARS, Anthrax, or H5N1. Pulmonary challenge with an inactivated H5N1 avian influenza virus rapidly induces ALI and OxPL formation in mice. Loss of TLR4 or TRIF expression protects mice from H5N1-induced ALI. Moreover, deletion of ncf1, which controls ROS production, improves the severity of H5N1-mediated ALI. Our data identify oxidative stress and innate immunity as key lung injury pathways that control the severity of ALI.


Asunto(s)
Estrés Oxidativo , Síndrome de Dificultad Respiratoria/metabolismo , Receptor Toll-Like 4/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Animales , Humanos , Gripe Humana/metabolismo , Interleucina-6/metabolismo , Pulmón , Ratones , Ratones Endogámicos C57BL , NADPH Oxidasas/metabolismo , FN-kappa B/metabolismo , Infecciones por Orthomyxoviridae/metabolismo , Fosfolípidos/metabolismo , Síndrome Respiratorio Agudo Grave/metabolismo , Transducción de Señal
2.
J Immunol ; 188(10): 5003-11, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22491245

RESUMEN

Chronic granulomatous disease (CGD) is an inherited disorder characterized by recurrent life-threatening bacterial and fungal infections. CGD results from defective production of reactive oxygen species by phagocytes caused by mutations in genes encoding the NADPH oxidase 2 (NOX2) complex subunits. Mice with a spontaneous mutation in Ncf1, which encodes the NCF1 (p47(phox)) subunit of NOX2, have defective phagocyte NOX2 activity. These mice occasionally develop local spontaneous infections by Staphylococcus xylosus or by the common CGD pathogen Staphylococcus aureus. Ncf1 mutant mice were more susceptible to systemic challenge with these bacteria than were wild-type mice. Transgenic Ncf1 mutant mice harboring the wild-type Ncf1 gene under the human CD68 promoter (MN(+) mice) gained the expression of NCF1 and functional NOX2 activity specifically in monocytes/macrophages, although minimal NOX2 activity was also detected in some CD11b(+)Ly6G(+) cells defined as neutrophils. MN(+) mice did not develop spontaneous infection and were more resistant to administered staphylococcal infections compared with MN(-) mice. Most strikingly, MN(+) mice survived after being administered Burkholderia cepacia, an opportunistic pathogen in CGD patients, whereas MN(-) mice died. Thus, monocyte/macrophage expression of functional NCF1 protected against spontaneous and administered bacterial infections.


Asunto(s)
Glicoproteínas de Membrana/biosíntesis , Monocitos/enzimología , Monocitos/microbiología , NADPH Oxidasas/biosíntesis , Especies Reactivas de Oxígeno/metabolismo , Infecciones Estafilocócicas/prevención & control , Animales , Antibacterianos/farmacología , Infecciones por Burkholderia/enzimología , Infecciones por Burkholderia/microbiología , Infecciones por Burkholderia/prevención & control , Burkholderia cepacia/inmunología , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Noqueados , Ratones Transgénicos , Monocitos/inmunología , NADPH Oxidasa 2 , NADPH Oxidasas/fisiología , Infecciones Estafilocócicas/enzimología , Infecciones Estafilocócicas/microbiología
3.
Hum Mol Genet ; 20(15): 3031-41, 2011 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-21565963

RESUMEN

Resolving the genetic basis of complex diseases like rheumatoid arthritis will require knowledge of the corresponding diseases in experimental animals to enable translational functional studies. Mapping of quantitative trait loci in mouse models of arthritis, such as collagen-induced arthritis (CIA), using F(2) crosses has been successful, but can resolve loci only to large chromosomal regions. Using an inbred-outbred cross design, we identified and fine-mapped CIA loci on a genome-wide scale. Heterogeneous stock mice were first intercrossed with an inbred strain, B10.Q, to introduce an arthritis permitting MHCII haplotype. Homozygous H2(q) mice were then selected to set up an F(3) generation with fixed major histocompatibility complex that was used for arthritis experiments. We identified 26 loci, 18 of which are novel, controlling arthritis traits such as incidence of disease, severity and time of onset and fine-mapped a number of previously mapped loci.


Asunto(s)
Artritis Experimental/genética , Artritis Reumatoide/genética , Modelos Animales de Enfermedad , Animales , Cruzamientos Genéticos , Femenino , Genotipo , Haplotipos , Complejo Mayor de Histocompatibilidad/genética , Masculino , Ratones , Sitios de Carácter Cuantitativo/genética
4.
Am J Pathol ; 181(1): 141-50, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22642907

RESUMEN

The suppressive role of phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX2) complex-derived reactive oxygen species (ROS) in adaptive immunity-driven arthritis models is well established. In this study, we aimed to investigate the role of NOX2 complex-derived ROS in a model of innate immunity-driven arthritis and to identify the ROS-regulated innate receptors that control arthritis. We used collagen antibody-induced arthritis (CAIA), which is a T and B lymphocyte-independent model of the effector phase of arthritis and is induced by well-defined monoclonal arthritogenic antibodies and enhanced by injection of lipopolysaccharide (LPS). CAIA was induced in both wild-type and Ncf1 mutant mice that lack phagocyte oxidative burst, and stimulated with LPS and other agents to activate innate immune responses. We found that both LPS and lipomannan enhanced CAIA more potently in the presence of functional phagocyte ROS production than in its absence. The ROS-dependent enhancement of CAIA was regulated by TLR2, but not by TLR4 stimulation, and was driven by granulocytes, whereas macrophages did not contribute to the phenotype. In addition, we report that collagen-induced arthritis was not affected by the functionality of the TLR4. We report that TLR2 signaling as an important ROS-regulated proinflammatory pathway leads to severe neutrophil-dependent inflammation in murine CAIA and conclude that the TLR2 pathway is modulated by phagocyte ROS to stimulate the development of arthritis.


Asunto(s)
Artritis Experimental/inmunología , Granulocitos/inmunología , Especies Reactivas de Oxígeno/inmunología , Receptor Toll-Like 2/inmunología , Envejecimiento/inmunología , Animales , Artritis Experimental/patología , Autoinmunidad/inmunología , Colágeno/inmunología , Inmunidad Innata , Lipopolisacáridos/inmunología , Macrófagos/inmunología , Masculino , Glicoproteínas de Membrana/inmunología , Ratones , Ratones Mutantes , NADPH Oxidasa 2 , NADPH Oxidasas/inmunología , Fagocitos/inmunología , Especies Reactivas de Oxígeno/metabolismo , Estallido Respiratorio/inmunología , Transducción de Señal/inmunología , Receptor Toll-Like 2/agonistas , Receptor Toll-Like 4/deficiencia , Receptor Toll-Like 4/inmunología
5.
Arthritis Rheum ; 64(11): 3594-603, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22886420

RESUMEN

OBJECTIVE: To identify genetic factors driving pathogenic autoantibody formation in collagen-induced arthritis (CIA), a mouse model of rheumatoid arthritis (RA), in order to better understand the etiology of RA and identify possible new avenues for therapeutic intervention. METHODS: We performed a genome-wide analysis of quantitative trait loci controlling autoantibody to type II collagen (anti-CII), anti-citrullinated protein antibody (ACPA), and rheumatoid factor (RF). To identify loci controlling autoantibody production, we induced CIA in a heterogeneous stock-derived mouse cohort, with contribution of 8 inbred mouse strains backcrossed to C57BL/10.Q. Serum samples were collected from 1,640 mice before arthritis onset and at the peak of the disease. Antibody concentrations were measured by standard enzyme-linked immunosorbent assay, and linkage analysis was performed using a linear regression-based method. RESULTS: We identified loci controlling formation of anti-CII of different IgG isotypes (IgG1, IgG3), antibodies to major CII epitopes (C1, J1, U1), antibodies to a citrullinated CII peptide (citC1), and RF. The anti-CII, ACPA, and RF responses were all found to be controlled by distinct genes, one of the most important loci being the immunoglobulin heavy chain locus. CONCLUSION: This comprehensive genetic analysis of autoantibody formation in CIA demonstrates an association not only of anti-CII, but interestingly also of ACPA and RF, with arthritis development in mice. These results underscore the importance of non-major histocompatibility complex genes in controlling the formation of clinically relevant autoantibodies.


Asunto(s)
Artritis Experimental/genética , Artritis Experimental/inmunología , Autoanticuerpos/genética , Autoanticuerpos/inmunología , Animales , Artritis Reumatoide/genética , Artritis Reumatoide/inmunología , Autoanticuerpos/sangre , Colágeno Tipo II/inmunología , Modelos Animales de Enfermedad , Femenino , Estudio de Asociación del Genoma Completo , Inmunoglobulina G/sangre , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Masculino , Ratones , Ratones Endogámicos A , Ratones Endogámicos AKR , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Endogámicos DBA , Péptidos Cíclicos/inmunología , Sitios de Carácter Cuantitativo/inmunología , Factor Reumatoide/inmunología , Especificidad de la Especie
6.
Eur J Immunol ; 41(2): 403-12, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21268010

RESUMEN

It is widely believed that DC, but not macrophages, prime naïve T cells in vivo. Here, we investigated the ability of CD68-expressing cells (commonly defined as macrophages) in priming autoreactive T cells and initiating collagen-induced arthritis (CIA) in the mouse. For this purpose, a transgenic mouse was developed (MBQ mouse) where macrophages exclusively expressed the MHC class II H2-A(q) (A(q)) on an H2-A(p) (A(p)) background. A(q), but not A(p) expression mediates susceptibility to CIA through presentation of type II collagen (CII) to T cells. CIA severity is enhanced by a mutation in the Ncf1 gene, impairing reactive oxygen species (ROS) production by the phagocyte NADPH oxidase (NOX2) complex. Expression of functional Ncf1 on macrophages was previously shown to protect from severe CIA. To study the effect of ROS on macrophage-mediated priming of T cells, the Ncf1 mutation was introduced in the MBQ mouse. Upon CII immunization, Ncf1-mutated MBQ mice, but not Ncf1 wild-type MBQ mice nor Ncf1-mutated A(p) mice, activated autoreactive T cells and developed CIA. These findings demonstrate for the first time that macrophages can initiate arthritis and that the process is negatively regulated by ROS produced via the NOX2 complex.


Asunto(s)
Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Artritis Experimental/inmunología , Activación de Linfocitos/inmunología , Macrófagos/inmunología , Especies Reactivas de Oxígeno/metabolismo , Linfocitos T/inmunología , Animales , Animales Congénicos , Presentación de Antígeno/genética , Presentación de Antígeno/inmunología , Antígenos CD/genética , Antígenos de Diferenciación Mielomonocítica/genética , Artritis Experimental/genética , Artritis Experimental/patología , Colágeno Tipo II/inmunología , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase II/metabolismo , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Interferón gamma/metabolismo , Interferón gamma/farmacología , Interleucina-2/metabolismo , Ganglios Linfáticos/citología , Ganglios Linfáticos/inmunología , Activación de Linfocitos/genética , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Ratones Transgénicos , NADPH Oxidasas/genética , Regiones Promotoras Genéticas/genética , Bazo/citología , Bazo/inmunología , Linfocitos T/metabolismo , Vacunación
7.
Am J Pathol ; 179(5): 2490-500, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21933654

RESUMEN

We established and characterized an arthritis mouse model using collagen type II (CII) and a thermo-responsive polymer, poly(N-isopropylacrylamide) (PNiPAAm). The new PNiPAAm adjuvant is TLR-independent, as all immunized TLR including MyD88-deficient mice developed an anti-CII response. Unlike other adjuvants, PNiPPAm did not skew the cytokine response (IL-1ß, IFN-γ, IL-4, and IL-17), as there was no immune deviation towards any one type of immune spectrum after immunization with CII/PNiPPAm. Hence, using PNiPAAm, we studied the actual immune response to the self-protein, CII. We observed arthritis and autoimmunity development in several murine strains having different major histocompatibility complex (MHC) haplotypes after CII/PNiPAAm immunization but with a clear MHC association pattern. Interestingly, C57Bl/6 mice did not develop CII-induced arthritis, with PNiPAAm demonstrating absolute requirement for a classical adjuvant. Presence of a gene (Ncf1) mutation in the NADPH oxidation complex has a profound influence in arthritis and using PNiPAAm we could show that the high CIA severity in Ncf1 mutated mice is independent of any classical adjuvant. Macrophages, neutrophils, eosinophils, and osteoclasts but not mast cells dominated the inflamed joints. Furthermore, arthritis induction in the adjuvant-free, eosinophil-dependent Vß12 DBA/1 mice could be shown to develop arthritis independent of eosinophils using CII/PNiPAAm. Thus, biocompatible and biodegradable PNiPAAm offers unique opportunities to study actual autoimmunity independent of TLR and a particular cytokine phenotype profile.


Asunto(s)
Acrilamidas/inmunología , Artritis Reumatoide/inmunología , Colágeno Tipo II/inmunología , Antígenos de Histocompatibilidad Clase II/genética , NADPH Oxidasas/genética , Receptores Toll-Like/inmunología , Resinas Acrílicas , Adyuvantes Inmunológicos , Animales , Anticuerpos/metabolismo , Formación de Anticuerpos , Artritis Reumatoide/genética , Colágeno Tipo II/efectos adversos , Citocinas/metabolismo , Inmunoglobulina G/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación/genética , Mutación/inmunología , Polímeros
8.
J Immunol ; 183(2): 874-81, 2009 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-19553535

RESUMEN

Reactive oxygen species (ROS) are important in the immune defense against invading pathogens, but they are also key molecules in the regulation of inflammatory reactions. Low levels of ROS production due to a polymorphism in the neutrophil cytosolic factor 1 (Ncf1) gene are associated with autoimmunity and arthritis severity in mouse models induced with adjuvant. We established an adjuvant-free arthritis model in which disease is induced by injection of the autoantigen collagen type II (CII) and depends on IL-5-producing T cells and eosinophils. In addition, the transgenic expression of mutated mouse CII allowed us to investigate an autoreactive immune response to an autologous Ag and by that natural tolerance mechanism. We show that a deficient ROS production, due to a spontaneous mutation in Ncf1, leads to increased autoantibody production and expansion of IL-33R-expressing T cells, impaired T cell tolerance toward tissue-specific CII, and severe arthritis in this unique model without disturbing adjuvant effects. These results demonstrate that the insufficient production of ROS promotes the breakdown of immune tolerance and development of autoimmune and adjuvant-free arthritis through an IL-5- and IL33R-dependent T cell activation pathway.


Asunto(s)
Artritis Experimental/etiología , Interleucina-5/metabolismo , NADPH Oxidasas/genética , Receptores de Interleucina-1/metabolismo , Receptores de Interleucina/metabolismo , Estallido Respiratorio/fisiología , Linfocitos T/patología , Animales , Artritis Experimental/inducido químicamente , Artritis Experimental/inmunología , Colágeno Tipo II/administración & dosificación , Colágeno Tipo II/efectos adversos , Proteína 1 Similar al Receptor de Interleucina-1 , Interleucina-33 , Interleucinas , Ratones , Ratones Endogámicos DBA , Ratones Noqueados , NADPH Oxidasas/fisiología , Especies Reactivas de Oxígeno/metabolismo , Linfocitos T/inmunología
9.
J Immunol ; 182(7): 4183-91, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19299716

RESUMEN

Permanent exposure to pathogens requires decisions toward tolerance or immunity as a prime task of dendritic cells. The molecular mechanisms preventing uncontrolled immune responses are not completely clear. We investigated the regulatory function of Ncf1, an organizing protein of NADPH oxidase, in the signaling cascade of Toll-like receptors. TLR9-stimulated spleen cells from both Ncf1-deficient and B10.Q mice with a point mutation in exon 8 of Ncf1 exhibited increased IL-12p70 secretion compared with controls. This finding was restricted to stimulatory CpG2216 and not induced by CpG2088. Because only CpG/TLR9-induced IL-12p70 was regulated by Ncf1, we used TRIF(-/-) and MyD88(-/-) cells to show that TLR9/MyD88 was primarily affected. Interestingly, additional experiments revealed that spleen cells from NOX2/gp91(phox)-deficient mice and the blocking of electron transfer by diphenylene iodonium had no influence on CpG-induced IL-12p70, confirming an NADPH oxidase-independent function of Ncf1. Finally, proving the in vivo relevance CpG adjuvant-guided OVA immunization resulted in a strong augmentation of IL-12p70-dependent Th1 IFN-gamma response only in Ncf1-deficient mice. These data suggest for the first time an important role for Ncf1 in the fine tuning of the TLR9/MyD88 pathway in vitro and in vivo that is independent of its role as an activator of NOX2.


Asunto(s)
Células Dendríticas/inmunología , Retroalimentación Fisiológica/inmunología , Interleucina-12/inmunología , NADPH Oxidasas/inmunología , Transducción de Señal/inmunología , Receptor Toll-Like 9/inmunología , Animales , Células Dendríticas/metabolismo , Citometría de Flujo , Interleucina-12/genética , Interleucina-12/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/inmunología , Factor 88 de Diferenciación Mieloide/metabolismo , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , ARN Mensajero/análisis , Especies Reactivas de Oxígeno/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptor Toll-Like 9/metabolismo
10.
J Immunol ; 182(7): 4432-8, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19299744

RESUMEN

We here present the first genetic fine mapping of experimental autoimmune neuritis (EAN), the animal model of Guillain-Barré syndrome, in a rat advanced intercross line. We identified and refined a total of five quantitative trait loci on rat chromosomes 4, 10, and 12 (RNO4, RNO10, RNO12), showing linkage to splenic IFN-gamma secretion and disease severity. All quantitative trait loci were shared with other models of complex inflammatory diseases. The quantitative trait locus showing strongest linkage to clinical disease was Ean6 and spans 4.3 Mb on RNO12, harboring the neutrophil cytosolic factor 1 (Ncf1) among other genes. Polymorphisms in Ncf1, a member of the NADPH oxidase complex, have been associated with disease regulation in experimental arthritis and encephalomyelitis. We therefore tested the Ncf1 pathway by treating rats with a NADPH oxidase complex activator and ameliorated EAN compared the oil-treated control group. By proving the therapeutic effect of stimulating the NADPH oxidase complex, our data strongly suggest the first identification of a gene regulating peripheral nervous system inflammation. Taken together with previous reports, our findings suggest a general role of Ncf1 and oxidative burst in pathogenesis of experimental autoimmune animal models.


Asunto(s)
Mapeo Cromosómico , NADPH Oxidasas/genética , Neuritis Autoinmune Experimental/genética , Neuritis Autoinmune Experimental/patología , Animales , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Autoantígenos/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Ligamiento Genético , Genotipo , Síndrome de Guillain-Barré/genética , Síndrome de Guillain-Barré/inmunología , Síndrome de Guillain-Barré/patología , Interferón gamma/inmunología , Interferón gamma/metabolismo , Masculino , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/inmunología , Complejos Multienzimáticos/metabolismo , NADH NADPH Oxidorreductasas/genética , NADH NADPH Oxidorreductasas/inmunología , NADH NADPH Oxidorreductasas/metabolismo , Neuritis Autoinmune Experimental/inmunología , Fitol/farmacología , Polimorfismo Genético , Sitios de Carácter Cuantitativo , Ratas , Estallido Respiratorio/fisiología
11.
J Clin Invest ; 117(10): 3020-8, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17909630

RESUMEN

Reduced capacity to produce ROS increases the severity of T cell-dependent arthritis in both mice and rats with polymorphisms in neutrophil cytosolic factor 1 (Ncf1) (p47phox). Since T cells cannot exert oxidative burst, we hypothesized that T cell responsiveness is downregulated by ROS produced by APCs. Macrophages have the highest burst capacity among APCs, so to study the effect of macrophage ROS on T cell activation, we developed transgenic mice expressing functional Ncf1 restricted to macrophages. Macrophage-restricted expression of functional Ncf1 restored arthritis resistance to the level of that of wild-type mice in a collagen-induced arthritis model but not in a T cell-independent anti-collagen antibody-induced arthritis model. T cell activation was downregulated and skewed toward Th2 in transgenic mice. In vitro, IL-2 production and T cell proliferation were suppressed by macrophage ROS, irrespective of T cell origin. IFN-gamma production, however, was independent of macrophage ROS but dependent on T cell origin. These effects were antigen dependent but not restricted to collagen type II. In conclusion, macrophage-derived ROS play a role in T cell selection, maturation, and differentiation, and also a suppressive role in T cell activation, and thereby mediate protection against autoimmune diseases like arthritis.


Asunto(s)
Artritis/inmunología , Autoinmunidad , Macrófagos/inmunología , Especies Reactivas de Oxígeno/metabolismo , Células TH1/inmunología , Animales , Células Presentadoras de Antígenos/inmunología , Antígenos/inmunología , Colágeno Tipo II/inmunología , Genotipo , Interferón gamma/metabolismo , Interleucina-2/metabolismo , Activación de Linfocitos , Ratones , Ratones Transgénicos , Mutación , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo
12.
Ann Rheum Dis ; 69(8): 1527-32, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20542961

RESUMEN

OBJECTIVES: The novel small molecule 9-chloro-2,3-dimethyl-6-(N,N-dimethylaminoethylamino-2-oxoethyl)-6H-indolo[2,3-b] quinoxaline (Rabeximod) reduces severity of arthritis in rodent models of rheumatoid arthritis (RA) and multiple sclerosis (MS). This study aimed to investigate the cellular target in vivo. METHODS: Collagen antibody-induced arthritis (CAIA) is induced by monoclonal collagen type II antibodies and enhanced by lipopolysaccharide. It was investigated how and when Rabeximod operates on inflammatory cells after stimulation of either Toll-like receptor (TLR)4 (lipopolysaccharide) or TLR2 (lipomannan) in mice lacking functional signalling through TLR4 due to a spontaneous deletion of the Tlr4 gene. RESULTS: Rabeximod efficiently prevented arthritis during the time window when TLR2 or TLR4 ligands activate inflammatory macrophages. The effect operated downstream of TLR activation as Rabeximod was highly therapeutic in CAIA enhanced through TLR2 stimuli in TLR4 deficient mice. In addition, it was found that the arthritis ameliorating effect of Rabeximod was time dependent, since inhibition of tumour necrosis factor alpha production from macrophages in vitro was more pronounced if administered close to stimulation. CONCLUSIONS: Rabeximod suppresses arthritis by preventing activation of inflammatory cells, most likely macrophages, in a time dependent fashion, downstream of TLR2 and TLR4 stimulation.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Experimental/tratamiento farmacológico , Indoles/uso terapéutico , Activación de Macrófagos/efectos de los fármacos , Quinoxalinas/uso terapéutico , Animales , Antirreumáticos/farmacología , Artritis Experimental/inmunología , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/inmunología , Evaluación Preclínica de Medicamentos , Indoles/farmacología , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/inmunología , Masculino , Ratones , Ratones Noqueados , Quinoxalinas/farmacología , Receptor Toll-Like 2/inmunología , Factor de Necrosis Tumoral alfa/biosíntesis
13.
Redox Biol ; 26: 101279, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31349119

RESUMEN

The phagocyte NADPH oxidase (the NOX2 complex) generates superoxide, the precursor to reactive oxygen species (ROS). ROS possess both antimicrobial and immunoregulatory function. Inactivating mutations in alleles of the NOX2 complex cause chronic granulomatous disease (CGD), characterized by an enhanced susceptibility to infections and autoimmune diseases such as Systemic lupus erythematosus (SLE). The latter is characterized by insufficient removal of dead cells, resulting in an autoimmune response against components of the cell's nucleus when non-cleared apoptotic cells lose their membrane integrity and present autoantigenic molecules in an inflammatory context. Here we aimed to shed light on the role of the NOX2 complex in handling of secondary necrotic cells (SNECs) and associated consequences for inflammation and autoimmunity during lupus. We show that individuals with SLE and CGD display accumulation of SNECs in blood monocytes and neutrophils. In a CGD phenotypic mouse strain (Ncf1** mice) build-up of SNECs in Ly6CHI blood monocytes was connected with a delayed degradation of the phagosomal cargo and accompanied by production of inflammatory mediators. Treatment with H2O2 or activators of ROS-formation reconstituted phagosomal abundance of SNECs to normal levels. Induction of experimental lupus further induced increased antibody-dependent uptake of SNECs into neutrophils. Lupus-primed Ncf1** neutrophils took up more SNECs than wild type neutrophils, whereas SNEC-accumulation in regulatory Ly6C-/LO monocytes was lower in Ncf1**mice. We deduce that the inflammatory rerouting of immune-stimulatory necrotic material into inflammatory phagocyte subsets contributes to the connection between low ROS production by the NOX2 complex and SLE.


Asunto(s)
NADPH Oxidasa 2/metabolismo , Fagocitos/metabolismo , Animales , Autoanticuerpos/inmunología , Citocinas/metabolismo , Concentración de Iones de Hidrógeno , Mediadores de Inflamación/metabolismo , Ratones , Monocitos/inmunología , Monocitos/metabolismo , NADPH Oxidasa 2/genética , Necrosis/genética , Necrosis/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismo , Fagocitos/inmunología , Fagocitosis/genética , Fagocitosis/inmunología , Fagosomas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores de IgG/metabolismo
14.
BMC Biol ; 5: 19, 2007 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-17490473

RESUMEN

BACKGROUND: A polymorphism in the activating component of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex, neutrophil cytosolic factor 1 (NCF1), has previously been identified as a regulator of arthritis severity in mice and rats. This discovery resulted in a search for NADPH oxidase-activating substances as a potential new approach to treat autoimmune disorders such as rheumatoid arthritis (RA). We have recently shown that compounds inducing NCF1-dependent oxidative burst, e.g. phytol, have a strong ameliorating effect on arthritis in rats. However, the underlying molecular mechanism is still not clearly understood. The aim of this study was to use gene-expression profiling to understand the protective effect against arthritis of activation of NADPH oxidase in the immune system. RESULTS: Subcutaneous administration of phytol leads to an accumulation of the compound in the inguinal lymph nodes, with peak levels being reached approximately 10 days after administration. Hence, global gene-expression profiling on inguinal lymph nodes was performed 10 days after the induction of pristane-induced arthritis (PIA) and phytol administration. The differentially expressed genes could be divided into two pathways, consisting of genes regulated by different interferons. IFN-gamma regulated the pathway associated with arthritis development, whereas IFN-beta regulated the pathway associated with disease protection through phytol. Importantly, these two molecular pathways were also confirmed to differentiate between the arthritis-susceptible dark agouti (DA) rat, (with an Ncf-1DA allele that allows only low oxidative burst), and the arthritis-protected DA.Ncf-1E3 rat (with an Ncf1E3 allele that allows a stronger oxidative burst). CONCLUSION: Naturally occurring genetic polymorphisms in the Ncf-1 gene modulate the activity of the NADPH oxidase complex, which strongly regulates the severity of arthritis. We now show that the Ncf-1 allele that enhances oxidative burst and protects against arthritis is operating through an IFN-beta-associated pathway, whereas the arthritis-driving allele operates through an IFN-gamma-associated pathway. Treatment of arthritis-susceptible rats with an NADPH oxidase-activating substance, phytol, protects against arthritis. Interestingly, the treatment led to a restoration of the oxidative-burst effect and induction of a strikingly similar IFN-beta-dependent pathway, as seen with the disease-protective Ncf1 polymorphism.


Asunto(s)
Artritis Experimental/enzimología , Interferón beta/metabolismo , NADPH Oxidasas/genética , NADP/metabolismo , Animales , Artritis Experimental/genética , Artritis Experimental/prevención & control , Activación Enzimática , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , NADPH Oxidasas/metabolismo , Fitol/farmacocinética , Fitol/farmacología , ARN Mensajero/genética , Ratas , Estallido Respiratorio , Terpenos , Distribución Tisular
15.
Antioxid Redox Signal ; 9(10): 1541-67, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17678439

RESUMEN

Autoimmune diseases such as rheumatoid arthritis (RA) are chronic diseases that cannot be prevented or cured If the pathologic basis of such disease would be known, it might be easier to develop new drugs interfering with critical pathway. Genetic analysis of animal models for autoimmune diseases can result in discovery of proteins and pathways that play key function in pathogenesis, which may provide rationales for new therapeutic strategies. Currently, only the MHC class II is clearly associated with human RA and animal models for RA. However, recent data from rats and mice with a polymorphism in Ncf1, a member of the NADPH oxidase complex, indicate a role for oxidative burst in protection from arthritis. Oxidative burst-activating substances can treat and prevent arthritis in rats, as efficiently as clinically applied drugs, suggesting a novel pathway to a therapeutic target in human RA. Here, the authors discuss the role of oxygen radicals in regulating the immune system and autoimmune disease. It is proposed that reactive oxygen species set the threshold for T cell activation and thereby regulate chronic autoimmune inflammatory diseases like RA. In the light of this new hypothesis, new possibilities for preventive and therapeutic treatment of chronic inflammatory diseases are discussed.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/fisiopatología , Especies Reactivas de Oxígeno , Animales , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Humanos , NADPH Oxidasas/metabolismo , Oxidación-Reducción , Linfocitos T/citología
16.
JCI Insight ; 2(10)2017 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-28515366

RESUMEN

Many effector mechanisms of neutrophils have been implicated in the pathogenesis of systemic lupus erythematosus (SLE). Neutrophil extracellular traps (NETs) have been assigned a particularly detrimental role. Here we investigated the functional impact of neutrophils and NETs on a mouse model of lupus triggered by intraperitoneal injection of the cell death-inducing alkane pristane. Pristane-induced lupus (PIL) was aggravated in 2 mouse strains with impaired induction of NET formation, i.e., NOX2-deficient (Ncf1-mutated) and peptidyl arginine deiminase 4-deficient (PAD4-deficient) mice, as seen from elevated levels of antinuclear autoantibodies (ANAs) and exacerbated glomerulonephritis. We observed a dramatically reduced ability to form pristane-induced NETs in vivo in both Ncf1-mutated and PAD4-deficient mice, accompanied by higher levels of inflammatory mediators in the peritoneum. Similarly, neutropenic Mcl-1ΔMyelo mice exhibited higher levels of ANAs, which indicates a regulatory function in lupus of NETs and neutrophils. Blood neutrophils from Ncf1-mutated and human individuals with SLE exhibited exuberant spontaneous NET formation. Treatment with specific chemical NOX2 activators induced NET formation and ameliorated PIL. Our findings suggest that aberrant NET is one of the factors promoting experimental lupus-like autoimmunity by uncontrolled release of inflammatory mediators.

17.
PLoS Med ; 3(9): e348, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16968121

RESUMEN

BACKGROUND: Despite recent successes with biological agents as therapy for autoimmune inflammatory diseases such as rheumatoid arthritis (RA), many patients fail to respond adequately to these treatments, making a continued search for new therapies extremely important. Recently, the prevailing hypothesis that reactive oxygen species (ROS) promote inflammation was challenged when polymorphisms in Ncf1, that decrease oxidative burst, were shown to increase disease severity in mouse and rat arthritis models. Based on these findings we developed a new therapy for arthritis using oxidative burst-inducing substances. METHODS AND FINDINGS: Treatment of rats with phytol (3,7,11,15-tetramethyl-2-hexadecene-1-ol) increased oxidative burst in vivo and thereby corrected the effect of the genetic polymorphism in arthritis-prone Ncf1(DA) rats. Importantly, phytol treatment also decreased the autoimmune response and ameliorated both the acute and chronic phases of arthritis. When compared to standard therapies for RA, anti-tumour necrosis factor-alpha and methotrexate, phytol showed equally good or better therapeutic properties. Finally, phytol mediated its effect within hours of administration and involved modulation of T cell activation, as injection prevented adoptive transfer of disease with arthritogenic T cells. CONCLUSIONS: Treatment of arthritis with ROS-promoting substances such as phytol targets a newly discovered pathway leading to autoimmune inflammatory disease and introduces a novel class of therapeutics for treatment of RA and possibly other chronic inflammatory diseases.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/metabolismo , Estallido Respiratorio/efectos de los fármacos , Animales , Artritis Experimental/patología , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , Células HL-60 , Humanos , Fitol/uso terapéutico , Ratas , Ratas Endogámicas Lew , Ratas Mutantes , Especies Reactivas de Oxígeno/metabolismo , Estallido Respiratorio/fisiología , Terpenos/uso terapéutico
18.
PLoS One ; 11(5): e0155936, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27227821

RESUMEN

BACKGROUND: To facilitate the development of therapies for rheumatoid arthritis (RA), the Innovative Medicines Initiative BTCure has combined the experience from several laboratories worldwide to establish a series of protocols for different animal models of arthritis that reflect the pathogenesis of RA. Here, we describe chronic pristane-induced arthritis (PIA) model in DA rats, and provide detailed instructions to set up and evaluate the model and for reporting data. METHODS: We optimized dose of pristane and immunization procedures and determined the effect of age, gender, and housing conditions. We further assessed cage-effects, reproducibility, and frequency of chronic arthritis, disease markers, and efficacy of standard and novel therapies. RESULTS: Out of 271 rats, 99.6% developed arthritis after pristane-administration. Mean values for day of onset, day of maximum arthritis severity and maximum clinical scores were 11.8±2.0 days, 20.3±5.1 days and 34.2±11 points on a 60-point scale, respectively. The mean frequency of chronic arthritis was 86% but approached 100% in long-term experiments over 110 days. Pristane was arthritogenic even at 5 microliters dose but needed to be administrated intradermally to induce robust disease with minimal variation. The development of arthritis was age-dependent but independent of gender and whether the rats were housed in conventional or barrier facilities. PIA correlated well with weight loss and acute phase reactants, and was ameliorated by etanercept, dexamethasone, cyclosporine A and fingolimod treatment. CONCLUSIONS: PIA has high incidence and excellent reproducibility. The chronic relapsing-remitting disease and limited systemic manifestations make it more suitable than adjuvant arthritis for long-term studies of joint-inflammation and screening and validation of new therapeutics.


Asunto(s)
Artritis Experimental/inducido químicamente , Artritis Experimental/patología , Artritis Reumatoide/inducido químicamente , Artritis Reumatoide/patología , Modelos Animales de Enfermedad , Inmunosupresores/toxicidad , Terpenos/toxicidad , Animales , Femenino , Masculino , Ratas
19.
Antioxid Redox Signal ; 23(5): 446-59, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-24359237

RESUMEN

SIGNIFICANCE: New insights into the role of reactive oxygen species (ROS) show that activators of the phagocyte NADPH oxidase 2 (NOX2) complex have the potential to be therapeutic in autoimmune and inflammatory conditions. It is, however, essential to elucidate the consequence of targeting the NOX2 complex, as it might lead to different outcomes depending on disease context and specificity, dose, and timing of ROS production. RECENT ADVANCES: Increasing evidence is suggesting that the role of the NOX2 complex is far more complex than previously anticipated. In addition to the well-described antimicrobial response, ROS also have immune and inflammatory regulatory effects. Compounds increasing NOX2-dependent ROS production have been shown to be effective both in preventing and in treating inflammatory manifestations in animal models of autoimmune diseases. Altogether, these results suggest the possibility of activating the NOX2 complex for the treatment of autoimmune inflammatory diseases while restoring and maintaining a balanced ROS regulation. CRITICAL ISSUES: The complexity of the NOX system and the derived ROS is important and must be considered when designing the programs for the development of NOX2-activating drugs, as well as for validation of selected hits, to successfully identify substances effective in treating inflammatory and autoimmune conditions. In addition, it is important to consider the complex downstream immunological effects and safety for drugs that increase the production of ROS. FUTURE DIRECTIONS: There is a strong potential for the development of ROS-inducing drugs, targeting the NOX2 complex, which are effective and safe, for the treatment of inflammatory autoimmune disorders. In such drug development, one must carefully investigate the pharmaceutical properties, including both efficacy and safety of the drugs. In addition, the immunological pathways of this new treatment strategy need careful examination.


Asunto(s)
Glicoproteínas de Membrana/farmacología , NADPH Oxidasas/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Enfermedades Autoinmunes/patología , Activación Enzimática/efectos de los fármacos , Humanos , Inflamación/patología , Glicoproteínas de Membrana/agonistas , NADPH Oxidasa 2 , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/inmunología
20.
Antioxid Redox Signal ; 21(16): 2231-45, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-24787605

RESUMEN

AIMS: Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by mutations in the phagocyte reactive oxygen species (ROS)-producing NOX2 enzyme complex and characterized by recurrent infections associated with hyperinflammatory and autoimmune manifestations. A translational, comparative analysis of CGD patients and the corresponding ROS-deficient Ncf1(m1J) mutated mouse model was performed to reveal the molecular pathways operating in NOX2 complex deficient inflammation. RESULTS: A prominent type I interferon (IFN) response signature that was accompanied by elevated autoantibody levels was identified in both mice and humans lacking functional NOX2 complex. To further underline the systemic lupus erythematosus (SLE)-related autoimmune process, we show that naïve Ncf1(m1J) mutated mice, similar to SLE patients, suffer from inflammatory kidney disease with IgG and C3 deposits in the glomeruli. Expression analysis of germ-free Ncf1(m1J) mutated mice reproduced the type I IFN signature, enabling us to conclude that the upregulated signaling pathway is of endogenous origin. INNOVATION: Our findings link the previously unexplained connection between ROS deficiency and increased susceptibility to autoimmunity by the discovery that activation of IFN signaling is a major pathway downstream of a deficient NOX2 complex in both mice and humans. CONCLUSION: We conclude that the lack of phagocyte-derived oxidative burst is associated with spontaneous autoimmunity and linked with type I IFN signature in both mice and humans.


Asunto(s)
Enfermedad Granulomatosa Crónica/genética , Inmunoglobulina G/inmunología , Interferón-alfa/genética , Interferón beta/genética , NADPH Oxidasas/genética , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/inmunología , Adolescente , Adulto , Animales , Autoinmunidad/inmunología , Niño , Preescolar , Complemento C3/inmunología , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Enfermedad Granulomatosa Crónica/inmunología , Humanos , Interferón-alfa/inmunología , Interferón beta/inmunología , Glomérulos Renales/inmunología , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Ratones , NADPH Oxidasa 2 , NADPH Oxidasas/inmunología , Adulto Joven
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