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- Haemodialysis in Diabetic Patients Modulates Inflammatory Cytokine Profile and T Cell Activation StatusPublication . Almeida, Ana Catarina Silva; Lourenço, Olga; Fonseca, A. M.Diabetic nephropathy (DN) is a common complication in patients with diabetes, and most of them need renal replacement therapy such as haemodialysis (HD). These patients have a high tendency to develop infections and exhibit anomalies in the immune system. The objective of this study was to assess the expression of activation-related markers on T cells, as well as to quantify inflammatory cytokines, before and after a single HD session in DN patients. The study involved DN patients under HD treatment who signed an informed consent form. Blood samples before and after one HD session were collected, to analyse the expression of CD25, CD69 and CD71 in T cells. We also quantified IL-12p70, IL-8, IL-10, IL-1β, TNF-α and IL-6 in serum samples using the cytometric bead array technique. After the HD session, there was an increase in the CD4/CD8 ratio due to significant alterations in both subsets. The relative percentage of CD25+ cells and CD8+ CD25+ increased significantly after the HD session, while the relative percentage of CD69 T cells decreased. There was a significant decrease in the CD25 mean fluorescence intensity values for CD4+ T, as well as in the case of CD71 in T cells after the HD session. Regarding cytokine synthesis, we found a significant increase in IL-10 and IL-6 and a decrease in IL-8 after HD session. This study showed that a HD session in DN patients affects the T cell activation status in the two major subpopulations and differentially modulates the production of inflammatory cytokines.
- Human CD8+ T Cells in Asthma: Possible Pathways and Roles for NK-Like SubtypesPublication . Lourenço, Olga; Fonseca, A M; Barata, Luis TabordaAsthma affects approximately 300 million people worldwide and is the most common chronic lung disease, which usually is associated with bronchial inflammation. Most research has focused upon the role of CD4+ T cells, and relatively few studies have addressed the phenotypic and functional roles of CD8+ T cell types and subtypes. Human NK-like CD8+ T cells may involve cells that have been described as CD8+CD28-, CD8+CD28-CD57+, CD8+CD27-, or CD8+ effector memory (TEM) cells, among other. However, most of the data that are available regarding these various cell types were obtained in murine models did not thoroughly characterize these cells with phenotypically or functionally or did not involve asthma-related settings. Nevertheless, one may conceptualize three principal roles for human NK-like CD8+ T cells in asthma: disease-promoting, regulatory, and/or tissue repair. Although evidence for some of these roles is scarce, it is possible to extrapolate some data from overlapping or related CD8+ T cell phenotypes, with caution. Clearly, further research is warranted, namely in terms of thorough functional and phenotypic characterization of human NK-like CD8+ T cells in human asthma of varying severity.
- Prevalence and clinical features of adverse food reactions in Portuguese adolescentsPublication . Lozoya-Ibáñez, Carlos; Morgado-Nunes, Sara; Rodrigues, Alexandra; Fernandes, Patrícia; Lourenço, Olga; Fonseca, Ana Mafalda; Barata, Luís TabordaBackground & aims: The objective of the present study was to determine, for the first time, the prevalence and clinical features of food allergy in Portuguese adolescents. Methods: Cross-sectional study performed in various secondary schools in central Portugal. Randomly selected adolescents replied to a validated food allergy questionnaire. Those who reported an adverse food reaction were seen at participating hospitals, where clinical history was taken, skin prick (SPT) and prick-prick skin (SPPT) tests were performed, and food allergen-specific IgE levels (sIgE) were determined. An open oral challenge was performed in selected cases. Cases of positive clinical history of immediate (up to 2 h after ingestion) reaction in association with positive food sIgE levels and/or SPT were classified as IgE-associated probable food allergy and as confirmed IgE-mediated food allergy if food challenges were positive. Cases of positive clinical history of delayed (more than 2 h after ingestion) and negative food sIgE levels independently of positive SPT or SPPT results, were classified as non-IgE associated probable food allergy. Results: The prevalence of probable food allergy in Portuguese adolescents was 1.41% (95% CI: 0.90–2.03%), with fresh fruits, shellfish, nuts, and peanut as the most frequently implicated foods. IgE-mediated probable food allergy occurred in 1.23% (95% CI: 0.67–1.72%) of cases, with fresh fruits, shellfish, and nuts mainly involved. Cutaneous symptoms were most frequently reported. Conclusions: The prevalence of probable food allergies in Portuguese adolescents is low, is mostly related to fresh fruits, shellfish, nuts, and peanut, and most frequently involves cutaneous symptoms.