Navegando por Palavras-chave "anticorpos"
Agora exibindo 1 - 2 de 2
Resultados por página
Opções de Ordenação
- ItemAcesso aberto (Open Access)Anticorpo anticitoplasma de neutrófilos (ANCA) em pioderma gangrenoso, um marcador sorológico para associação com doenças sistêmicas: estudo de oito casos(Sociedade Brasileira de Dermatologia, 2004-02-01) Cabral, Virgínia Lúcia Ribeiro [UNIFESP]; Miszputen, Sender Jankiel [UNIFESP]; Catapani, Wilson Roberto; Universidade Federal de São Paulo (UNIFESP); Faculdade de Medicina do ABCBACKGROUND: The pathogenesis of Ulcerative Colitis (UC) and its extraintestinal manifestations remain uncertain, although involvement of the immune system is emphasized. The likely importance of neutrophils is demonstrated by detection of the antineutrophil cytoplasmic antibody (ANCA) in this inflammatory bowel disease. Pyoderma Gangrenosum (PG) is an idiopathic skin condition and a rare cutaneous manifestation of UC. ANCA has also been reported in the latter dermatosis. OBJECTIVES: To invetigate the relationship between clinical features of UC and the appearance of PG and its association with ANCA. PATIENTS AND METHODS: ANCA was determined in sera from eight patients with PG. Four out of eight patients had pyoderma gangrenosum associated-UC, and in four cases no identified systemic disease was associated. RESULTS: The search for ANCA yielded negative results in sera from all four patients with pyoderma not associated with systemic disease. Two cases with active and extensive colitis associated with PG and primary sclerosing cholangitis (PSC) were positive for ANCA. Sera from two other patients with both UC and PG had negative test results. CONCLUSIONS: The presence of ANCA in patients with PG associated with UC and PSC suggests that its association with PSC is responsible for ANCA positivity in this subset of patients.
- ItemAcesso aberto (Open Access)Caracterização clínica, molecular e imunológica de pacientes com síndrome poliglandular autoimune do tipo 1(Universidade Federal de São Paulo (UNIFESP), 2016-01-27) Weiler, Fernanda Guimarães [UNIFESP]; Castro, Marise Lazaretti [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Introduction: Autoimmune polyendocrine syndrome type 1 (APS1) is an autosomal recessive disorder defined by the association of at least two of the three major diseases: chronic mucocutaneous candidiasis (CMC), hypoparathyroidism, and autoimmune adrenal insufficiency, however, many other autoimmune components may develop. In most cases, APS1 appears in infancy or childhood. The disease is caused by mutations in the AIRE gene, resulting in defective AIRE protein, which is essential for self-tolerance through thymic expression of peripheral self-proteins, and deletion of autoreactive T cells. In Brazil, however, the characteristics of APS1 patients are still unknown. Objective: To define the clinical profile of Brazilian APS1 patients; to perform mutational analysis of AIRE gene; to investigate genotype/phenotype correlations; to perform functional study of a novel mutation; and to measure specific autoantibodies. Patients and methods: Information about clinical history was evaluated by a questionnaire, and antibodies against interferon type I and interleukins 17A, 17F and 22 were measured in the sera of the patients. Genomic DNA was used to perform sequencing of all 14 exons and exon/intron boundaries of the AIRE gene. For localization analysis by immunofluorescence microscopy, HeLa cells were transfected with wild-type and mutant (c.560C>G) plasmids. Results: Thirteen patients with clinical diagnosis of APS1 were identified and in all cases the disease first appeared during infancy or childhood. Twenty different manifestations have been diagnosed. Besides being the first sign in the majority (77%), CMC was also the most frequent manifestation, present in all patients. Hypoparathyroidism was observed in 69% and adrenal insufficiency was diagnosed in 77%, while the complete triad was present in 54% of the sample. Every patient carried defects in AIRE, and among 10 identified mutations, 4 have never been reported (c.560C>G, c.966C>A, c.1096-2A>G and c.1347C>A). The most frequent mutation was the c.967_979del, which accounted for 36% of the alleles. As in other series, we were unable to identify correlations between phenotype and the detected mutations. Mutational analyses of relatives allowed the identification of APS1 in an asymptomatic child. In transiently transfected cells, the mutant c.560C>G protein was observed as abnormal perinuclear aggregates, which suggested the mutation harmful potential. All 10 confirmed APS1 patients that were tested for anti-interferon type I showed positive results, and we have found that anti-interleukin-17A titers were negatively correlated with number of manifestations in each patient. Thirteen patients suspected of having the syndrome were also investigated; one of them displayed another new mutation of AIRE, which is expected to be deleterious according to in silico simulations. Conclusions: We were able to identify 14 Brazilian patients with APS1, one of them still asymptomatic. In our cohort, CMC was the most prevalent disease, while the most common mutation was c.967_979del. We detected 4 novel mutations, and another mutation likely to be deleterious in a patient suspected of having the syndrome was also reported. Titers of anti-interleukin-17A were negatively correlated with number of manifestations. Screening for AIRE mutations and analysis of specific auto-antibodies are useful tools to establish the diagnosis in initial or atypical situations.