Objetivo: Avaliar a citologia cérvico-vaginal em adolescentes com lúpus eritematoso sistêmico juvenil (LESJ) e comparar com controles. Material e métodos: Cinqüenta e duas adolescentes com LESJ (critérios do American College of Rheumatology) foram comparadas com 52 controles saudáveis. Todos os esfregaços de Papanicolaou foram avaliados por uma mesma citopatologista, que desconhecia o exame ginecológico, e foram classificados de acordo com o Sistema de Bethesda, 2001. Resultados: As médias das idades das pacientes com LESJ e controles foram similares (16,17 ± 1,94 versus 16,13 ± 2,16 anos, p=0,92). A citologia cérvico-vaginal foi similar em ambos os grupos, embora as relações sexuais no último mês tenham sido menos freqüentes nas pacientes com LESJ em relação aos controles (23% versus 59,6%, p=0,0003). Apenas uma paciente (2%) com LESJ e duas controles (4%) tinham displasia cervical (LIE-BG) e papilomavírus humano (HPV) (p=1,0). Citologia cérvico-vaginal inflamatória foi observada em 21 (60%) das pacientes com SLEDAI maior ou igual a 4 e em apenas 4 (23%) daqueles com SLEDAI < 4 (p=0,001). Assim como, uma maior freqüência de achados inflamatórios também foi observada em adolescentes virgens com LESJ (57% versus 8%, p=0,005). Vaginite por Candida spp foi observada em 7 pacientes com LESJ (14%) e em nenhuma dos controles (p=0,012), e foi associada com uso de drogas imunossupressoras (p=0,01) e dose alta de prednisona (p=0,002). Conclusão: Nossos achados indicam que o trato genital feminino é um órgão alvo no LESJ, pois inflamação cérvico-vaginal está associada com atividade da doença independentemente da atividade sexual. / Objective: To evaluate cervicovaginal cytology in adolescents with juvenile systemic lupus erythematosus (JSLE) and to compare them to controls. Material and methods: Fifty-two female adolescents with JSLE (American College of Rheumatology criteria) were compared to 52 age-matched healthy controls. All Pap smears were evaluated by the same cytopathologist blinded to gynecology examination, and performed according to the Bethesda Classification System 2001. Results: The mean age of JSLE patients and controls were similar (16.17 ± 1.94 vs. 16.13 ± 2.16 years, p=0.92). The cervicovaginal cytology was found to be similar in both groups, although sexual intercourses in the last month were less frequent in JSLE than controls (23% vs. 59.6%, p=0.0003). Only one patient (2%) with JSLE versus two controls (4%) had cervical dysplasia (LGSIL) and human papilomavirus (p=1.0). Inflammatory cervicovaginal cytology was observed in 21 (60%) of patients with SLEDAI ? 4 and only 4(23%) of those with SLEDAI<4 (p=0.001). Likewise, a higher frequency of inflammatory changes were also observed in virgin JSLE (57% vs. 8%, p=0.005). Candida spp vaginitis was observed in 7 JSLE (14%) versus none in controls (p=0.012) and was associated to immunosuppressive drugs (p=0.01) and high dose of prednisone (p=0.002). Conclusion: Our findings supports the notion that female genital tract is a target organ in SLE since cervical inflammation is associated to disease activity independently of sexual activity.

O anticorpo anti-proteína P ribossomal é um marcador sorológico do lúpus eritematoso sistêmico. Nós avaliamos a relevância do mesmo em discriminar os padrões histopatológicos de nefrite lúpica. O anti-P foi detectado em 18/81(22%) dos pacientes com envolvimento renal confirmado por biópsia. Foi observada uma freqüência aumentada deste anticorpo em pacientes com classe V (72%) comparado com outras classes de nefrite (28%), p=0.005. Dentro do esperado, pacientes anti-P positivos tiveram um nível médio de proteinúria mais elevado que pacientes anti-P negativos (6,4 + 4,8 vs. 4,7 + 3,9 g/dl, p= 0,046). É ainda interessante que a maioria dos pacientes com anti-P isolado tinha classe V, e 71%apresentaram o padrão membranoso puro. O anti-P parece ser um novo marcador sorológico para a nefrite lúpica membranosa. / Anti-ribosomal P antibody is a serological marker for systemic lupus erythematosus. We have evaluated its relevance in discriminating histopathologic patterns of lupus nephritis. Anti-P was detected in 18/81 (22%) patients with biopsy proven renal involvement. A higher frequency of this antibody was observed in patients with class V (72%) compared to other classes of renal disease (28%), p=0.005. Accordingly, anti-P positive patients had higher mean proteinuria level than anti-P antibody negative patients (6.4 + 4.8 vs. 4.7 + 3.9 g/dl, p= 0.046). Interestingly, the majority of patients with isolated anti-P had class V, and 71% displayed a pure membranous pattern. Anti-P seems to be a novel serological marker for membranous lupus nephritis.

Objetivo: Avaliar a citologia cérvico-vaginal em adolescentes com lúpus eritematoso sistêmico juvenil (LESJ) e comparar com controles. Material e métodos: Cinqüenta e duas adolescentes com LESJ (critérios do American College of Rheumatology) foram comparadas com 52 controles saudáveis. Todos os esfregaços de Papanicolaou foram avaliados por uma mesma citopatologista, que desconhecia o exame ginecológico, e foram classificados de acordo com o Sistema de Bethesda, 2001. Resultados: As médias das idades das pacientes com LESJ e controles foram similares (16,17 ± 1,94 versus 16,13 ± 2,16 anos, p=0,92). A citologia cérvico-vaginal foi similar em ambos os grupos, embora as relações sexuais no último mês tenham sido menos freqüentes nas pacientes com LESJ em relação aos controles (23% versus 59,6%, p=0,0003). Apenas uma paciente (2%) com LESJ e duas controles (4%) tinham displasia cervical (LIE-BG) e papilomavírus humano (HPV) (p=1,0). Citologia cérvico-vaginal inflamatória foi observada em 21 (60%) das pacientes com SLEDAI maior ou igual a 4 e em apenas 4 (23%) daqueles com SLEDAI < 4 (p=0,001). Assim como, uma maior freqüência de achados inflamatórios também foi observada em adolescentes virgens com LESJ (57% versus 8%, p=0,005). Vaginite por Candida spp foi observada em 7 pacientes com LESJ (14%) e em nenhuma dos controles (p=0,012), e foi associada com uso de drogas imunossupressoras (p=0,01) e dose alta de prednisona (p=0,002). Conclusão: Nossos achados indicam que o trato genital feminino é um órgão alvo no LESJ, pois inflamação cérvico-vaginal está associada com atividade da doença independentemente da atividade sexual. / Objective: To evaluate cervicovaginal cytology in adolescents with juvenile systemic lupus erythematosus (JSLE) and to compare them to controls. Material and methods: Fifty-two female adolescents with JSLE (American College of Rheumatology criteria) were compared to 52 age-matched healthy controls. All Pap smears were evaluated by the same cytopathologist blinded to gynecology examination, and performed according to the Bethesda Classification System 2001. Results: The mean age of JSLE patients and controls were similar (16.17 ± 1.94 vs. 16.13 ± 2.16 years, p=0.92). The cervicovaginal cytology was found to be similar in both groups, although sexual intercourses in the last month were less frequent in JSLE than controls (23% vs. 59.6%, p=0.0003). Only one patient (2%) with JSLE versus two controls (4%) had cervical dysplasia (LGSIL) and human papilomavirus (p=1.0). Inflammatory cervicovaginal cytology was observed in 21 (60%) of patients with SLEDAI ? 4 and only 4(23%) of those with SLEDAI<4 (p=0.001). Likewise, a higher frequency of inflammatory changes were also observed in virgin JSLE (57% vs. 8%, p=0.005). Candida spp vaginitis was observed in 7 JSLE (14%) versus none in controls (p=0.012) and was associated to immunosuppressive drugs (p=0.01) and high dose of prednisone (p=0.002). Conclusion: Our findings supports the notion that female genital tract is a target organ in SLE since cervical inflammation is associated to disease activity independently of sexual activity.

Les patients atteints de lupus érythémateux systémique ont une augmentation de la prévalence du syndrome métabolique (MetS) mais les mécanismes sous-jacents ne sont pas connus. Le récepteur de type Toll 7 (TLR7), qui reconnait de l’ARN simple brin, joue un rôle important dans la défense anti-microbienne de l’hôte, mais contribue également au développement et à la progression du lupus. Cependant, l’implication de TLR7 dans le MetS est inconnue. L’objectif de mon projet de thèse était d’explorer l’idée nouvelle que la signalisation de TLR7 peut conduire non seulement au lupus mais aussi à des anomalies métaboliques.Nous avons trouvé que l’obésité induite par un régime riche en gras (régime HFD) a conduit à une exacerbation du lupus et de paramètres métaboliques dans des souris TLR8ko, qui développent spontanément une auto-immunité de type lupique à cause d’une augmentation de la signalisation de TLR7 dans les cellules dendritiques (DCs). Au contraire, sous un régime HFD, les souris TLR7/8ko n’ont pas développé de lupus, et les souris TLR7ko et TLR7/8ko ont été protégées contre les anomalies métaboliques incluant l'augmentation de poids et l’intolérance au glucose. De manière intéressante, dans des souris sauvages (WT) le régime HFD a conduit à une augmentation de l’expression de TLR7 et de la production de TNF par les DCs spléniques et hépatiques, et ce phénotype était plus profond dans les souris TLR8ko. Mon étude montre l’implication de la signalisation de TLR7 dans l’interconnexion entre le lupus et les anomalies métaboliques, donc cibler TLR7 pourrait constituer une nouvelle approche comme thérapie contre le lupus et les maladies métaboliques. / Systemic lupus erythematosus (SLE) patients have increased prevalence of metabolic syndrome but the underlying mechanisms are unknown. Toll-like receptor 7 (TLR7) that detects single stranded-RNA plays a key role in antimicrobial host defence, but also contributes in the initiation and progression of SLE. However, the implication of TLR7 in MetS is unknown. The objective of my PhD project was to explore the novel idea that TLR7 signalling can lead not only to SLE but also to metabolic abnormalities. We found that high fat diet (HFD)-induced obesity led to exacerbation of lupus and metabolic parameters in TLR8ko mice, which develop spontaneous lupus-like disease due to increased TLR7 signalling by dendritic cells (DCs). In contrast, upon HFD TLR7/8ko mice did not develop SLE, and both TLR7ko and TLR7/8ko mice were protected from metabolic abnormalities including body weight gain and glucose intolerance. Interestingly, in wild-type mice HFD led to an increase of TLR7 expression and TNF production by hepatic and splenic DCs, and this phenotype was more profound in TLR8ko mice. My study uncovers the implication of TLR7 signalling in the interconnection of SLE and metabolic abnormalities, thus targeting TLR7 might be a novel approach as a tailored therapy in SLE and metabolic diseases.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

O lúpus eritematoso sistêmico (LES) é uma doença autoimune cuja fisiopatologia envolve mecanismos imunológicos, incluindo distúrbios nos processos de morte celular e nos mecanismos de eliminação de autoantígenos e de tolerância, acompanhados da formação de autoanticorpos patogênicos. Ele acomete principalmente mulheres jovens e a gestação nestas pacientes apresenta significativa morbimortalidade. Os achados clínicos e laboratoriais na nefrite lúpica são semelhantes àqueles encontrados em pacientes com pré-eclâmpsia (PE), especificamente hipertensão arterial, proteinúria e edema. Foi proposto o uso de fatores angiogênicos, como o fator de crescimento vascular endotelial (VEGF) e o fator de crescimento placentário (PlGF), e antiangiogênicos, como o receptor Fms-like tirosina quinase 1 solúvel (sFlt-1), para o diagnóstico diferencial entre estas duas condições, no entanto os dados disponíveis na literatura sobre estas citocinas em pacientes não gestantes com LES são inconsistentes. Este estudo foi desenhado para avaliar se existe diferença entre os níveis séricos de VEGF, PlGF e sFlt-1 em pacientes com LES com e sem atividade sistêmica da doença e se existe diferença nesses fatores quando comparamos pacientes com LES e mulheres saudáveis. Foram incluídas 54 mulheres com diagnóstico de LES em acompanhamento no ambulatório de Reumatologia do HUPE-UERJ, sem outra doença autoimune diagnosticada, e divididas de acordo com a atividade da doença. 30 pacientes tinham doença inativa (SLEDAI médio: 0,7) e 24 tinham doença ativa (SLEDAI médio: 11,6). 23 mulheres deste último grupo possuíam nefrite ativa, enquanto 20 das pacientes com doença em remissão já haviam apresentado nefrite ao longo da evolução do LES. O grupo controle foi formado por 34 mulheres hígidas atendidas no ambulatório de ginecologia da Policlínica Piquet Carneiro-UERJ. Considerando as três citocinas estudadas, as pacientes com LES apresentaram valores séricos médios superiores às mulheres do grupo controle (VEGF: 319,0 + 226,0 x 206,2 + 119,4, p=0,02; PlGF: 42,2 + 54,1 x 13,6 + 21,6, p=0,02; sFlt-1: 107,9 + 49,2 x 70,2 + 95,0, p=0,01). O grupo de pacientes com doença ativa também apresentou média superior ao controle nos três fatores (VEGF: 331,0 + 216,8 x 206,2 + 119,4, p=0,02; PlGF: 41,2 + 47,3 x 13,6 + 21,6, p=0,02; sFlt-1: 120,5 + 42,4 x 70,2 + 95,0, p=0,02), enquanto não foi encontrada diferença estatística entre o grupo de LES inativo e o controle. A média do sFlt-1 sérico foi maior nas pacientes com LES ativo do que a média das pacientes com a doença em remissão (120,5 + 54,9 x 97,8 + 42,4, p=0,02), mas não houve diferença significativa da média do VEGF e PlGF séricos entre os dois grupos. O melhor entendimento dos fatores angiogênicos e antiangiogênicos em pacientes com LES proporcionado por este estudo nos permite a análise dessas citocinas em gestantes com LES e, possivelmente, sua posterior aplicação como método diferencial entre nefrite lúpica e PE. / Systemic lupus erythematosus (SLE) is an autoimmune disease which pathophysiology involves immunological mechanisms including disturbances in the processes of cell death and mechanisms of elimination of autoantigens and tolerance, accompanied by formation of pathogenic autoantibodies. It mainly affects young women and pregnancy in these patients have significant morbidity and mortality. Clinical and laboratory findings in lupus nephritis are similar to those found in patients with preeclampsia (PE), specifically hypertension, proteinuria and edema. It has been proposed the use of angiogenic factors, such as vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), and antiangiogenic factors, as soluble Fms-like tyrosine kinase-1 (sFlt-1), for the differential diagnosis between these two conditions, however available data in the literature about these cytokines in non-pregnant SLE patients are inconsistent. This study was designed to evaluate whether there are differences between serum levels of VEGF, PlGF and sFlt-1 in SLE patients with and without systemic disease activity and whether there are differences in these factors when comparing SLE patients with healthy women. 54 women with SLE followed at outpatient clinic of Rheumatology HUPE - UERJ were included. They had no other autoimmune disease diagnosed and were divided according to disease activity. 30 patients had inactive disease (mean SLEDAI: 0.7), and 24 had active disease (mean SLEDAI: 11.6). 23 women in this latter group had active nephritis, while 20 patients with inactive disease had history of lupus nephritis. The control group consisted of 34 healthy women who attended the Gynecology outpatient clinic at Policlínica Piquet Carneiro - UERJ. Considering the three studied cytokines, the SLE patients had higher mean serum levels than the control group (VEGF: 319.0 + 226.0 x 206.2 + 119.4, p=0.02; PlGF: 42.2 + 54.1 x 13.6 + 21.6, p=0.02; sFlt-1: 107.9 + 49.2 x 70.2 + 95.0, p=0.01). The group of patients with active disease also had higher mean levels of all three factors than controls (VEGF: 331.0 + 216.8 x 206.2 + 119.4, p=0.02; PlGF: 41.2 + 47.3 x 13.6 + 21.6, p=0.02; sFlt-1: 120.5 + 42.4 x 70.2 + 95.0, p=0.02), whereas no statistical difference was found between the group with inactive SLE and the control group. The mean sFlt-1 levels were higher in patients with active SLE than the mean levels of patients with inactive disease (120.5 + 54.9 x 97.8 + 42.4, p=0.02), but there was no significant difference in mean serum of VEGF and PlGF levels between these two groups. A better understanding of angiogenic and antiangiogenic factors in patients with SLE provided by this study allows the analysis of these cytokines in pregnant woman with SLE and possibly their subsequent application as differential method between PE and lupus nephritis.

Le lupus érythémateux disséminé (LED) est une maladie auto-immune systémique caractérisée par une inflammation provoquant des lésions dans de nombreux organes tels que les reins, les poumons ou la peau. Dans cette pathologie, une activation excessive du système immunitaire conduit à la production d’auto-anticorps dirigés, le plus souvent, contre du matériel nucléaire. La différenciation des lymphocytes B (LB) en cellules productrices d’anticorps requiert une communication entre les LT et les LB. Ce dialogue est régulé par de nombreux acteurs cellulaires et moléculaires afin de permettre la mise en place d’une réponse humorale efficace en cas d’infections, mais aussi de prévenir le développement de maladies auto-immunes. Mon projet de thèse a consisté à étudier l’implication de deux de ces acteurs, l’un favorisant la différenciation des LB en plasmocytes, à savoir, les cellules T folliculaires auxiliaires (TFH) et le second régulant négativement l’activation lymphocytaire, le récepteur co-inhibiteur BTLA (pour B and T Lymphocyte Attenuator) dans le LED chez l’Homme. Au cours de cette étude, nous avons d’une part amélioré les connaissances concernant les sous-populations de TFH circulantes humaines, en décrivant que parmi les cellules TFH CXCR3-CCR6- sont retrouvées des cellules aux propriétés suppressives. De plus, nous avons suggéré que la contraction des TFH1 (CXCR3+CCR6-) au profit des TFH2 (CXCR3-CCR6-), observées chez les patients lupiques, pourrait être le reflet d’une migration des TFH1 vers les organes inflammés. D’autre part, nous avons mis en évidence un défaut fonctionnel de BTLA dans les LT CD4+ de patients lupiques. Ce défaut, restauré en normalisant le métabolisme lipidique des LT CD4+, semble associé à la sévérité de la pathologie. En parallèle de ces observations, nous avons démontré un défaut d’expression de BTLA sur les LB et les LT CD4+ régulateurs de patients lupiques. L’ensemble de nos données sont prometteuses et ouvrent de nouvelles perspectives thérapeutiques pour le traitement du LED. / Systemic Lupus Erythematosus (SLE) is an autoimmune disease characterized by lesions in several organs such as kidneys, lungs and skin for instance. In this pathology, an excessive activation of the immune system leads to the production of autoantibodies targeting mainly nuclear antigens. B cell differentiation into antibody-secreting cells requires a close collaboration between T and B cells. This cross-talk is regulated by various cellular and molecular factors in order to mount an efficient humoral response in case of infection, but also to prevent autoimmune disease development. The aim of my thesis was to study two regulating factors of the B cell response, one promoting the B cell differentiation into plasma cells, i.e the follicular helper T cells (TFH) and the other one inhibiting lymphocyte activation, i.e a co-inhibitory receptor called BTLA (« B and T Lymphocyte Attenuator ») in human SLE. In this study, we first improved our knowledge concerning human circulating TFH cells, by describing among the CXCR3-CCR6- TFH cell subset, a population with suppressive capacities. Moreover, we suggested that the decreased frequency of TFH1 in lupus patients’ blood could be explained by the migration of these cells into inflamed tissues. We also highlighted a BTLA functional deficiency in lupus CD4+ T cells. This deficiency, which can be restored by normalizing the lipid metabolism, seems to be associated to disease severity. Furthermore, we described an altered expression of BTLA in lupus B cells and regulatory T cells. Altogether, our data show promising results and suggest new potential therapeutic strategies for lupus treatment.

Introdução: A vitamina D tem ações pleiotrópicas em muitas doenças crônicas. A expressão do receptor da vitamina D (VDR - vitamin D receptor) em diversas células do sistema imune reforça a possível influência da vitamina D nas doenças autoimunes. Polimorfismos genéticos localizados no gene VDR podem determinar alterações nos mecanismos de ação da vitamina D, porém com resultados ainda pouco conhecidos. O polimorfismo BsmI do gene VDR foi associado com lúpus eritematoso sistêmico (LES) em pacientes asiáticos. Estudos com pacientes lúpicos no Brasil ainda não foram realizados. Objetivos: Investigar a possibilidade dos polimorfismos BsmI e FokI do gene VDR aumentarem o risco para o desenvolvimento do LES e avaliar a possível associação destes polimorfismos com manifestações clínicas e laboratoriais da doença. Determinar os níveis séricos da 25-hidroxivitamina D [25(OH)D)] nos pacientes e investigar a possível associação das suas concentrações com os polimorfismos estudados e expressões clínicas e laboratoriais do LES. Materiais e métodos: Estudo caso-controle envolvendo 195 pacientes com LES e 201 controles saudáveis da mesma área geográfica. Foram pesquisados os polimorfismos BsmI e FokI do gene VDR. Os níveis séricos da 25(OH)D foram dosados nos casos. A genotipagem foi realizada por Restriction Fragment Length Polymorphism-Polimerase Chain Reaction (RFLP-PCR), usando primers e enzimas de restrição específicas para cada polimorfismo. A dosagem da 25(OH)D foi realizada por quimioluminescência. Os dados clínicos e laboratoriais foram coletados dos prontuários. Resultados: Não houve diferença estatisticamente significativa nas frequências genotípicas e alélicas dos polimorfismos BsmI e FokI entre casos e controles eurodescendentes. Não houve associação entre as manifestações clínicas e laboratoriais do LES e os polimorfismos estudados. Os níveis séricos médios da 25(OH)D foram de 25,51±11,43 ng/ml nos pacientes com LES. Quando os pacientes foram classificados pelo estado de vitamina D, a seguinte distribuição foi observada: 55 (30,4%) normais (≥30 ng/ml), 63 (34,8%) insuficientes (20-30 ng/ml), 52 (28,7%) deficientes (<20 ng/ml) e 11 (6,1%) com níveis criticamente baixos (<10 ng/ml). Cinquenta e seis por cento dos pacientes com deficiência estavam usando pelo menos 800 UI de vitamina D por dia. Baseada na distribuição genotípica, a concentração da 25(OH)D foi significativamente maior nos pacientes com genótipo f/f, quando comparados com os pacientes com genótipo F/F (31,614,1 ng/ml versus 23,09,2 ng/ml, p=0,004). Níveis de vitamina D não foram associados com aspectos clínicos e laboratoriais do LES. Conclusões: Os polimorfismos BsmI e FokI não apresentaram associação com LES nos nossos pacientes eurodescendentes estudados. O polimorfimo FokI mostrou influência significativa nos níveis da 25(OH)D, o que reforça o papel deste polimorfismo na atividade funcional do VDR. Este achado poderia ser considerado em futuros estudos clínicos e experimentais envolvendo dosagem da vitamina D. A concentração da 25(OH)D necessária para manter o bom funcionamento do sistema musculoesquelético, cardiovascular e imunológico deveria ser individualizada para cada paciente e novas orientações sobre a suplementação de vitamina D poderiam ter que levar em consideração a ancestralidade genética. Assim, estudos adicionais são necessários para estabelecer definições dos níveis ideais de vitamina D geneticamente especificados. / Introduction: Vitamin D has pleiotropic actions on many chronic diseases. The expression of the VDR (vitamin D receptor) in various cells of the immune system strengthens the possible influence of vitamin D on autoimmune diseases. Genetic polymorphisms located in VDR gene may determine changes in the mechanisms of action of vitamin D, but with results still unknown. The BsmI VDR polymorphism was associated with systemic lupus erythematosus (SLE) in Asian patients. Studies with SLE patients in Brazil have not been conducted. Objectives: To investigate the possibility of BsmI and FokI polymorphisms of VDR gene causing increased risk for development of SLE and to evaluate the possible association of these polymorphisms with clinical and laboratory manifestations of the disease. To determine serum levels of 25-hydroxyvitamin D [25(OH)D)] in patients and to investigate the possible association of their concentrations with the studied polymorphisms and clinical and laboratory expressions of SLE. Materials and methods: Case-control study involving 195 SLE patients and 201 healthy controls from the same geographical area. The BsmI and FokI polymorphisms of VDR gene were studied. Serum 25(OH)D levels were measured in the cases. Genotyping was performed by Restriction Fragment Length Polymorphism-Polymerase Chain Reaction (RFLP-PCR), using primers and restriction enzymes specific for each polymorphism. The measurement of 25(OH)D was performed by chemiluminescence. The clinical and laboratory data were collected from medical records. Results: There was no statistically significant difference in genotypic and allelic frequencies of BsmI and FokI polymorphisms among European-derived cases and controls. There was no association between clinical and laboratory features in SLE patients and the studied polymorphisms. The mean serum levels of 25(OH)D were 25.51±11.43 ng/ml in SLE patients. When patients were classified according to vitamin D status, the following distribution was observed: 55 (30.4%) had normal (≥30 ng/ml), 63 (34.8%) insufficient (20-30 ng/ml), 52 (28.7%) deficient (<20 ng/ml) and 11 (6,1%) critically low serum levels (<10 ng/ml). Fifty six percent of patients with deficiency received at least 800 IU of vitamin D per day. Based on genotype distribution, 25(OH)D levels were significantly higher in patients carrying the f/f genotype, when compared to patients carrying the F/F genotype (31.614.1 ng/ml versus 23.09.2 ng/ml, p=0.004). Vitamin D levels were not associated with clinical and laboratory features of SLE. Conclusions: The BsmI and FokI polymorphisms did not present association with SLE in our European-derived studied patients. The FokI polymorphism showed significant influence on 25(OH)D levels, reinforcing its role in functional activity of VDR. This finding may be considered in future clinical and experimental studies involving vitamin D measurements. Serum concentrations of 25(OH)D required to maintain optimal musculoskeletal, cardiovascular and immune health should be individualized for each patient and new guidelines about vitamin D supplementation may have to take into consideration the individual genetic background. Genetic-specific definitions of ideal levels of vitamin D in SLE should therefore be established in future studies.

Les femmes développent une réponse immunitaire plus forte que celle des hommes. Ceci les protège vis-à-vis des infections virales ou bactériennes, mais augmente également leur risque de développer une pathologie auto-immune. Le lupus érythemateux systémique (LES) est une pathologie auto-immune prototypique à fort dimorphisme sexuel, avec 9 femmes affectées pour 1 homme. TLR7 (Toll-like receptor 7) est un TLR endosomal spécifique de l'ARN simple brin. Ce récepteur joue un rôle crucial dans la réponse antivirale mais aussi dans la rupture de tolérance à la base de la pathologie lupique. Sa surexpression dans un modèle murin suffit à induire le développement spontané d'un lupus. Au contraire, son invalidation dans des souches de souris développant un lupus spontané, est protectrice. Chez l'Homme, TLR7 est exprimé dans les cellules dendritiques plasmacytoïdes (pDC), les monocytes, ainsi que dans les lymphocytes B (LB). Son engagement induit la production de médiateurs pro-inflammatoires par les pDC et les monocytes, et la maturation et la production d'anticorps par les LB. Le gène TLR7 est porté sur le bras court du chromosome X. Un mécanisme compensatoire du dosage des gènes portés sur les gonosomes intervient dans les cellules des mammifères, où un des deux chromosomes X est aléatoirement inactivé pendant le développement embryonnaire. Or ce mécanisme est imparfait et, chez les femmes, au minimum 15% des gènes portés sur l'X sont susceptibles d'échapper à son inactivation. Vu l'effet du dosage de Tlr7 dans les modèles murins du lupus, et de la localisation de TLR7 sur le chromosome X humain, nous avons cherché à déterminer si TLR7 serait sujet à l'échappement à l'inactivation de l'X chez les femmes. Pour cela nous avons développé une approche basée sur l'analyse sur cellule unique de l'expression d'un marqueur allélique au niveau des transcrits de TLR7. Nos résultats démontrent que ce gène échappe à l'inactivation du chromosome X dans 30% environ des LB, monocytes et pDC de femmes saines. De plus, nous avons observé par une technique d'hybridation in situ la transcription simultanée des deux allèles. L'expression bi-allélique de TLR7 est associée à une augmentation significative de l'ARNm de TLR7 dans les LB naïfs. Enfin, nos résultats démontrent que les LB naïfs exprimant les deux allèles de TLR7 sont préférentiellement enrichis dans les cellules différentiées dont la commutation de classe a été induite par un ligand de TLR7. De la même façon, les cellules plasmocytaires où TLR7 échappe à l'inactivation de l'X sont enrichies parmi les cellules prolifératrices en réponse à l'engagement de TLR7. En conclusion, ce travail démontre que le gène TLR7 échappe à l'inactivation de l'X chez plusieurs types de cellules immunitaires, que le dosage des transcrits du gène s'en trouve augmenté chez les lymphocytes B, et que la réponse biologique à l'engagement TLR7 est plus importante chez les lymphocytes B à expression bi-allélique. Par ailleurs, de premiers résultats mettent en évidence l'échappement de TLR7 à l'inactivation de l'X chez des hommes atteints du syndrome de Klinefelter (47, XXY). Ceci pourrait expliquer leur susceptibilité équivalente à celle des femmes au développement du lupus. / Women develop stronger immune responses than men, with positive effects on the resistance to viral or bacterial infections but magnifying also the susceptibility to autoimmune diseases like systemic lupus erythematosus (SLE), which affects 9 women per 1 man. Toll-like receptor 7 (TLR7) is an endosomal single-stranded RNA sensor that plays a key role in the initiation of the antiviral response. TLR7 dosage, however, is also a crucial determinant in SLE, and Tlr7 overexpression suffices to induce spontaneous lupus-like disease. Conversely, Tlr7 knock-out abolishes SLE development in lupus-prone mice. In humans, TLR7 is expressed in plasmacytoid dendritic cells (pDCs), monocytes and B lymphocytes. TLR7 engagement increases B cell maturation and production of antibodies, but also the production of pro-inflammatory cytokines by pDCs and monocytes. Human TLR7 is encoded on the short arm of the X chromosome. The cells of female mammals randomly inactivate one X chromosome in the course of embryonic development to equalize gene dosage between the sexes. However, 15% of X-linked human genes consistently escape inactivation so that both alleles are expressed in individual cells. Because increased dosage of TLR7 expression due to non-inactivation could contribute to autoimmunity, we investigated allelic expression of TLR7 in individual immune cells from women using a TLR7 allelic marker observable on mRNA molecules. Our results show that TLR7 escapes X chromosome inactivation in about 30% of B cells, pDCs and monocytes. TLR7 bi-allelic expression was observed also in situ by RNA-FISH. Naive B cell TLR7 bi-allelic expression is accompanied by higher TLR7 mRNA expression. Our results demonstrate that TLR7 escape from X-inactivation is associated with an enhanced plasma cell proliferative response to TLR7 ligands, and promotes immunoglobulin class switch induced by T cell help and TLR7 engagement. Our study provides proof of principle that TLR7 escapes from X chromosome inactivation in several types of immune cells of women and results in greater transcriptional expression, and shows also that cellular function in bi-allelic B cells is augmented in a TLR7-specific manner. Bi-allelic expression of TLR7 in women is thus a potential risk factor in the pathogenesis of SLE. Our initial results show also that TLR7 escapes from X inactivation in the immune cells of men with Klinefelter syndrome (47, XXY), which may explain a risk of SLE equivalent to women's.

O lúpus eritematoso sistêmico (LES) é uma doença autoimune cuja fisiopatologia envolve mecanismos imunológicos, incluindo distúrbios nos processos de morte celular e nos mecanismos de eliminação de autoantígenos e de tolerância, acompanhados da formação de autoanticorpos patogênicos. Ele acomete principalmente mulheres jovens e a gestação nestas pacientes apresenta significativa morbimortalidade. Os achados clínicos e laboratoriais na nefrite lúpica são semelhantes àqueles encontrados em pacientes com pré-eclâmpsia (PE), especificamente hipertensão arterial, proteinúria e edema. Foi proposto o uso de fatores angiogênicos, como o fator de crescimento vascular endotelial (VEGF) e o fator de crescimento placentário (PlGF), e antiangiogênicos, como o receptor Fms-like tirosina quinase 1 solúvel (sFlt-1), para o diagnóstico diferencial entre estas duas condições, no entanto os dados disponíveis na literatura sobre estas citocinas em pacientes não gestantes com LES são inconsistentes. Este estudo foi desenhado para avaliar se existe diferença entre os níveis séricos de VEGF, PlGF e sFlt-1 em pacientes com LES com e sem atividade sistêmica da doença e se existe diferença nesses fatores quando comparamos pacientes com LES e mulheres saudáveis. Foram incluídas 54 mulheres com diagnóstico de LES em acompanhamento no ambulatório de Reumatologia do HUPE-UERJ, sem outra doença autoimune diagnosticada, e divididas de acordo com a atividade da doença. 30 pacientes tinham doença inativa (SLEDAI médio: 0,7) e 24 tinham doença ativa (SLEDAI médio: 11,6). 23 mulheres deste último grupo possuíam nefrite ativa, enquanto 20 das pacientes com doença em remissão já haviam apresentado nefrite ao longo da evolução do LES. O grupo controle foi formado por 34 mulheres hígidas atendidas no ambulatório de ginecologia da Policlínica Piquet Carneiro-UERJ. Considerando as três citocinas estudadas, as pacientes com LES apresentaram valores séricos médios superiores às mulheres do grupo controle (VEGF: 319,0 + 226,0 x 206,2 + 119,4, p=0,02; PlGF: 42,2 + 54,1 x 13,6 + 21,6, p=0,02; sFlt-1: 107,9 + 49,2 x 70,2 + 95,0, p=0,01). O grupo de pacientes com doença ativa também apresentou média superior ao controle nos três fatores (VEGF: 331,0 + 216,8 x 206,2 + 119,4, p=0,02; PlGF: 41,2 + 47,3 x 13,6 + 21,6, p=0,02; sFlt-1: 120,5 + 42,4 x 70,2 + 95,0, p=0,02), enquanto não foi encontrada diferença estatística entre o grupo de LES inativo e o controle. A média do sFlt-1 sérico foi maior nas pacientes com LES ativo do que a média das pacientes com a doença em remissão (120,5 + 54,9 x 97,8 + 42,4, p=0,02), mas não houve diferença significativa da média do VEGF e PlGF séricos entre os dois grupos. O melhor entendimento dos fatores angiogênicos e antiangiogênicos em pacientes com LES proporcionado por este estudo nos permite a análise dessas citocinas em gestantes com LES e, possivelmente, sua posterior aplicação como método diferencial entre nefrite lúpica e PE. / Systemic lupus erythematosus (SLE) is an autoimmune disease which pathophysiology involves immunological mechanisms including disturbances in the processes of cell death and mechanisms of elimination of autoantigens and tolerance, accompanied by formation of pathogenic autoantibodies. It mainly affects young women and pregnancy in these patients have significant morbidity and mortality. Clinical and laboratory findings in lupus nephritis are similar to those found in patients with preeclampsia (PE), specifically hypertension, proteinuria and edema. It has been proposed the use of angiogenic factors, such as vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), and antiangiogenic factors, as soluble Fms-like tyrosine kinase-1 (sFlt-1), for the differential diagnosis between these two conditions, however available data in the literature about these cytokines in non-pregnant SLE patients are inconsistent. This study was designed to evaluate whether there are differences between serum levels of VEGF, PlGF and sFlt-1 in SLE patients with and without systemic disease activity and whether there are differences in these factors when comparing SLE patients with healthy women. 54 women with SLE followed at outpatient clinic of Rheumatology HUPE - UERJ were included. They had no other autoimmune disease diagnosed and were divided according to disease activity. 30 patients had inactive disease (mean SLEDAI: 0.7), and 24 had active disease (mean SLEDAI: 11.6). 23 women in this latter group had active nephritis, while 20 patients with inactive disease had history of lupus nephritis. The control group consisted of 34 healthy women who attended the Gynecology outpatient clinic at Policlínica Piquet Carneiro - UERJ. Considering the three studied cytokines, the SLE patients had higher mean serum levels than the control group (VEGF: 319.0 + 226.0 x 206.2 + 119.4, p=0.02; PlGF: 42.2 + 54.1 x 13.6 + 21.6, p=0.02; sFlt-1: 107.9 + 49.2 x 70.2 + 95.0, p=0.01). The group of patients with active disease also had higher mean levels of all three factors than controls (VEGF: 331.0 + 216.8 x 206.2 + 119.4, p=0.02; PlGF: 41.2 + 47.3 x 13.6 + 21.6, p=0.02; sFlt-1: 120.5 + 42.4 x 70.2 + 95.0, p=0.02), whereas no statistical difference was found between the group with inactive SLE and the control group. The mean sFlt-1 levels were higher in patients with active SLE than the mean levels of patients with inactive disease (120.5 + 54.9 x 97.8 + 42.4, p=0.02), but there was no significant difference in mean serum of VEGF and PlGF levels between these two groups. A better understanding of angiogenic and antiangiogenic factors in patients with SLE provided by this study allows the analysis of these cytokines in pregnant woman with SLE and possibly their subsequent application as differential method between PE and lupus nephritis.