Doutorado em Medicina Tropical e Saúde Pública (IPTSP)
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Navegando Doutorado em Medicina Tropical e Saúde Pública (IPTSP) por Por Orientador "Dias, Fátima Ribeiro"
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Item Avaliação da participação de citocinas (interleucina 32, interleucina 10, fator de necrose tumoral) e receptores similares a Toll (TLR 4) na infecção por Leishmania (Viannia) sp.(Universidade Federal de Goiás, 2013-07-26) Galdino Júnior, Hélio; Dias, Fátima Ribeiro; http://lattes.cnpq.br/5741031258926403; Dias, Fátima Ribeiro; Junqueira, Maria Imaculada Muniz Barboza; Shio, Marina Tiemi; Marques, Mara Rubia; Lino Júnior, Ruy de SouzaAmerican Tegumentary Leishmaniasis (ATL) is a disease caused by protozoa Leishmania. In Brazil, the most prevalent species is L. (Viannia) braziliensis. Several cytokines and receptors are involved in immunopathogenesis of ATL, however, the role of interleukin 32 (IL-32) was not investigated in this disease. Besides, toll-like receptors (TLR) were poorly evaluated in Leishmania infection, especially when it is caused by L. (V.) braziliensis. The aim of the present study was to evaluate IL-32, TNF and IL-10 expression in ATL lesions; the induction of IL-32 by L. (V.) braziliensis amastigotes in human peripheral blood mononuclear cells (PBMC) cultures as well as the involvement of TLR4 in monocyte/macrophage response to L. (V.) brazilienis amastigotes. Biopsies fragments from cutaneous and mucosal lesion and healthy tissues were used to investigate the subgenus of the parasites by PCR-RFLP assay; expression of IL-32, TNF and IL-10 was assayed by immunohistochemistry and expression of IL-32 isoforms , TNF and IL-10 was analysed by qRT-PCR. The PBMC were cultured with L. (V.) braziliensis amastigotes in the absence or presence of IFN and IL-32 induction was assayed by qRT-PCR; and TNF and IL-10, by ELISA. TLR4 was neutralized by monoclonal antibodies and lipopolysaccharide (LPS) was used as TLR4 agonist. The expression of TLR4 in monocyte/macrophages was evaluated by flow cytometry. Thirty five patients were evaluated, 23 with cutaneous leishmaniasis (CL) and 12 with mucosal leihsmaniasis (ML). All parasite positive samples contained L. (Viannia) sp. The expression of IL-32 (protein and mRNA) was similar in CL and ML lesions but was higher than in health tissues. Only IL-32 was detected. The proteins TNF and IL-10 were detected in similar levels in CL and ML lesions, but TNF mRNA was present in higher levels in ML (4.069x) than in CL lesions (141 x, p < 0.05). L. (V.) braziliensis amastigotes induced IL-32, TNF and IL-10 in IFN pre-treated PBMC. The production of TNF and IL-10 was TLR4 dependent and treatment of PBMC with LPS further increased the production of TNF induced by amastigotes (p < 0.05). However, LPS did not altere the IL-10 production. Treatment with IFN enhanced the percentage of TLR4+ monocyte/macrophage (p < 0.05), which was decreased following incubation with amastigotes (p = 0.06). The results showed that IL-32 is produced during L. (Viannia) infection and TLR4 mediates L. (V.) braziliensis amastigote-induced TNF and IL-10 production in human PBMC. Moreover, the data suggest that amastigotes can lead to TLR4 internalization what can allow parasite to evade of innate immune response. This study indicates that IL-32 and TLR4 are important players in human infection caused by L. (Viannia), especially L. (V.) braziliensis. Whether TLR4 is also important to IL-32 production by human monocytes/macrophages deserves further investigation.Item Avaliação de receptores similares a toll (tlrs) em monócitos de pacientes com doença de Parkinson(Universidade Federal de Goiás, 2017-06-02) Rocha Sobrinho, Hermínio Maurício da; Dias, Fátima Ribeiro; http://lattes.cnpq.br/5741031258926403; Dias, Fátima Ribeiro; Silva, Marcos Vinícius da; Cruvinel, Wilson de Melo; Diniz, Denise Sisterolli; Gomes, Rodrigo SaarParkinson's disease (PD) is a condition of the central nervous system (CNS), chronic and progressive, resulting from the death of brain dopamine-producing neurons. Genetic and epidemiological studies have highlighted the role of neuroinflammation in the pathophysiology of PD, emphasizing that the process of neuroinflammation is associated with the death of dopaminergic neurons. In peripheral blood or tissues, leukocytes activated by pathogen-associated molecular patterns (PAMP) and / or tissue damage (DAMP), via Toll-like receptors (TLR), produce pro and antiinflammatory mediators whose imbalance can lead to a chronic inflammation. Under physiological conditions, three subpopulations of human peripheral blood monocytes are detected: the classical monocytes (CD14++CD16-), the intermediates (CD14++CD16++) and the non-classical (CD14+CD16+), these cells present phenotypic and functional differences that can influence the characteristics of the immune response against DAMPs or PAMPs. The aim of this study was to compare the peripheral blood leukocyte potential of patients with PD or healthy individuals in the production of cytokines (TNFα and IL-10) after stimulation of these cells with TLR4 (LPS) or TLR2 / 1 (Pam3Cys) agonists, to evaluate the effect of the age of DP patients on the production of cytokines in blood cultures, to investigate the percentage of monocyte subpopulations expressing TLR1, TLR2 and TLR10, to evaluate the influence of TLR10 expression on the biological activity of TLR2 to its agonist in PBMC cultures. Two groups of patients with PD were evaluated (≤ 55 years old and ≥ 65 years old), age-matched with healthy controls (n = 26). 6 h-TNFα production was increased after TLR4 stimulation, mainly in young PD patients, whereas TLR2-induced TNFα and IL-10 levels were decreased in PD patients independent of age (p < 0.05). A reverse correlation between LPS-induced TNFα production and age was observed in PD patients and controls, but TNFα induced by TLR2 agonist was not associated with age of PD patients or controls. TNFα production induced by TLR4 but not by TLR2 was reversely associated with the age at PD onset and disease duration. No associations between UPDRS scores and cytokine levels were detected. A higher percentage of CD14++CD16+ monocyte subpopulation was observed in the blood of patients with PD compared to healthy controls, as well as a higher percentage of monocytes from patients expressing TLR10. The expression of TLR2 and TLR10 in peripheral blood monocytes from PD patients was increased relative to that of healthy controls. The results suggest that the peripheral blood leukocyte response to the TLR2 ligand is reduced in PD and that the elevation of TLR10 expression in monocytes influences inhibiting the biological activity of TLR2 to its agonist as demonstrated in the neutralization experiment of TLR10. In this study, the group of DP patients with the highest severity of the disease, evaluated by the UPDRS scale, had a lower percentage of monocytes expressing TLR10, suggesting the expression of this receptor in peripheral blood leukocytes as a possible prognostic marker for DP. These findings, together, may play an important role in the immunopathology of PD. The study of TLR cell expression in peripheral leukocytes and CNS, intracellular signaling pathways and the production of pro and anti-inflammatory mediators is necessary in order to better clarify the role of TLR in the PD pathogenesis and perhaps for the identification of biomarkers of disease prognosis in the blood PD patients.Item Neuroinflamação na doença de Parkinson: avaliação de citocinas induzidas via Toll like receptors em células do sangue periférico(Universidade Federal de Goiás, 2014-08-29) Silva, Delson José da; Dias, Fátima Ribeiro; http://lattes.cnpq.br/5741031258926403; Dias, Fátima Ribeiro; Teixeira, Antônio Lúcio; Vilela Filho, Osvaldo; Pfrimer, Araci Hoffmann; Ragazzo, Paulo CésarParkinson’s disease (PD) is as a neurodegenerative disorder caused by neuron loss in the substantia nigra, which produces dopamine. Evidences suggest that several inflammatory cytokines are enhanced in the brain and blood of patients presenting with PD. These cytokines might be induced by Toll-like receptor (TLR) activation. In peripheral blood, monocytes express TLR and may participate in the immunopathogenicity of neurodegenerative diseases. The objectives of this work were: carry out a literature review about neuroinflammation in PD; assess possible alterations in production of inflammatory cytokines in blood cultures of patients presenting with PD activated by TLR agonists; evaluate the percentages of the two main monocyte subpopulations, as well as TLR2 and TLR4 expression in these subpopulations in peripheral blood of patients presenting with PD. Patients presenting with PD (n = 31) and healthy individuals (n = 31), matched by gender and age, were evaluated and the patients were assessed regarding the severity of their neurological and psychiatric symptoms using the Hoen & Yahr scale (H&Y) and the Unified Parkinson’s Disease Rating Scale (UPDRS). Blood cultures were activated with TLR2 agonists (Pam3Cys), TLR4 (LPS), or TLR7/8 (R848). Cytokines (TNF, IL-1β, IL-6, IL-12p70, and IL-10) were Abstract 12 quantified in the serum and supernatant of blood cultures using Cytometer bead array. Monocytes (CD14+CD16– and CD14+CD16+) and TLR2 and TLR4 expression were identified using flow cytometry. Cytokine concentrations in the serum of patients and controls were similar and no significant association was found between cytokine concentrations and UPDRS scores. However, after activation of blood cultures of patients, a significant decreased response to TLR2 (TNF, IL-1β, IL-6, IL-10) and TLR7/8 (IL-6) agonists was observed. No correlation was observed between the concentrations of cytokines induced by TLR2 or TLR7/8 agonists and UPDRS scores. The percentages of monocytes CD14+CD16– and CD14+CD16+ did not significantly differ between patients and controls, and no alterations in TLR2 or TLR4 expressions were detected in these monocyte subpopulations in patients. The results indicate that leukocytes, especially monocytes, of patients presenting with PD show decreased capacity to respond to the activation via TLR2. This decrease may be associated with the previous activation of TLR2 in vivo, making the cells tolerant to new stimuli ex vivo. Assessing the activation of monocytes in peripheral blood, via TLR, may help the evaluation of the neurodegenerative/ neuroinflammatory process in PD, contributing to a better understanding of the pathophysiology of this disease.