Análise do perfil fenotípico e funcional das células natural Killer e linfócitos TCD8+ no Líquen plano / Analysis of phenotypic and functional profile of Natural Killer cells and CD8 + T lymphocytes in Lichen planus

Líquen plano (LP) é uma doença mucocutânea de natureza inflamatória crônica de etiologia ainda desconhecida. Alterações na resposta imune inata, como aos padrões moleculares associados à patógenos (PAMPs) e padrões moleculares associados ao dano (DAMPs) podem levar à inflamação crônica e contribuir com a patogênese do LP. OBJETIVO: Avaliar o efeito da ativação via o DAMP S100A8 e o receptor Toll-like 4 (TLR-4) em células Natural killer (NK) e TCD8 citotóxicas e suas subpopulações de memória/efetoras em pacientes com LP. MÉTODOS: Foram selecionados 25 pacientes com LP (22 mulheres, 3 homens) com idade média de 43,46 anos ± 8,46 e um grupo controle com 25 indivíduos (22 mulheres, 3 homens) com idade média de 42 anos ± 5,5. A determinação transcricional e da expressão por imunohistoquimica dos DAMPs S100A8, HMGB-1 e de TLR-4 e RAGE foi realizada em biópsias de lesões cutâneas de indivíduos com LP, e os níveis séricos de S100A8, HMGB-1, MICA e MICB foram determinados por ELISA. As células mononucleares (CMNs) de sangue periférico foram avaliadas por citometria de fluxo quanto a frequência de TNF, IL-1beta e o marcador de desgranulação CD107a em células TCD8+ e células NK CD56+ e suas subpopulações. A avaliação da via de sinalização de TLR em células TCD8+ purificadas e ativadas com S100A8 foi analisada por PCR array e a determinação da expressão de mRNA dos componentes do inflamassoma em células TCD8+ ativadas com S100A8 por PCR em tempo real. RESULTADOS: Foi evidenciado nos indivíduos com LP elevada expressão da proteína S100A8 nas lesões cutâneas e de HMGB-1, TLR-4 e RAGE na derme, em paralelo ao aumento da expressão de mRNAs para S100A8 e S100A9 e diminuição de RAGE. Além disto, uma elevação dos níveis séricos do dímero S100A8/A9 foi detectada nos pacientes comparados aos controles, ao contrário do DAMP HMGB-1 que mostrou níveis similares em ambos os grupos. A influência do S100A8 em células TCD8+ e células NK, foi analisada em CMNs pela ativação...

Lichen planus (LP) is a mucocutaneous inflammatory chronic disease of unknown etiology. Alterations in the innate immune response such as the pathogen-associated molecular pattern (PAMPs) and damage-associated molecular pattern (DAMPs) can lead to chronic inflammation and contribute to the pathogenesis of LP. OBJECTIVE: Evaluate the effect of the activation trough the DAMP S100A8 and the Toll-like receptor 4 (TLR-4) on the Natural killer cells (NK) and cytotoxic TCD8 cells and their memory / effector subsets in LP disease. METHODS: We selected 25 patients with LP (22 women, 3 men) with a mean age of 43.46 years ± 8.46 and a control group of 25 subjects (22 women, 3 men) with a mean age of 42 ± 5, 5. The transcriptional determination and protein expression by immunohistochemistry of DAMPs, S100A8 and HMGB-1 as well as TLR-4 and RAGE was performed on biopsies of skin lesions from patients with LP, and serum levels of S100A8, HMGB-1, MICA and MICB were determined by ELISA. Peripheral blood mononuclear cells (PBMCs) were assessed by flow cytometry to evaluate the frequency of TNF, IL-1beta and the degranulation marker CD107a in CD8+ T cells and CD56 + NK cells and their subsets. The evaluation of the TLR signaling pathway in purified CD8 + T cells activated with S100A8 were analyzed by PCR array and the determination of mRNA expression of inflammasome components on CD8 + T cells activated by S100A8 was measured by real time PCR. RESULTS: It was shown in the LP individuals an increased expression of the S100A8 protein in the cutaneous lesions and HMGB-1, TLR-4 and RAGE in the dermis, in parallel to increased level of mRNAs for S100A8 and S100A9 and decreased expression of RAGE. Moerover, increased serum levels of the dimer S100A8 / A9 was detected in patients compared to controls, in contrast to DAMP HMGB1 that revealed similar levels in both groups. The influence of S100A8 in CD8 + T cells and NK cells, was analyzed in PBMC activating with...

Polymerase chain reaction for the evaluation of Schistosoma mansoni infection in two low endemicity areas of Minas Gerais, Brazil

This study aimed to evaluate the occurrence of schistosomiasis in areas with low endemicity using polymerase chain reaction (PCR) as a diagnostic method. We analysed faecal samples from 219 individuals residing in Piau and Coronel Pacheco, state of Minas Gerais, Brazil, using a single faecal sample from each individual and two slides of the Kato-Katz technique as a gold standard. Fifteen out of the 219 samples were positive with both methods of diagnosis. One sample was diagnosed as positive by the Kato-Katz technique only and 61 were diagnosed only by PCR. The positivity rates were 7.3% with the Kato-Katz method and 34.7% with PCR. When both techniques were assumed to have 100% specificity and positive individuals were identified by both methods, the sensitivity of the Kato-Katz method was 20.8% and the PCR sensitivity was 98.7%. The Kappa index between the two techniques was 0.234, suggesting weak agreement. The assessment of a single faecal sample by PCR detected more cases of infection than the analysis of one sample with two slides using the Kato-Katz technique, suggesting that PCR can be a useful diagnostic tool, particularly in areas with low endemicity.