DEFAR - Departamento de Farmácia
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530
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Item Posttherapeutic cure criteria in Chagas disease : conventional serology followed by supplementary serological, parasitological, and molecular tests.(2012) Assis, Girley Francisco Machado de; Silva, Alexandre Rotondo da; Bem, Vitor Antônio Lemos do; Bahia, Maria Terezinha; Martins Filho, Olindo Assis; Dias, João Carlos Pinto; Viñas, Pedro Albajar; Torres, Rosália Morais; Lana, Marta deWe performed a critical study of conventional serology, followed by supplementary serological, parasitological, and molecular tests, to assess the response to etiologic treatment of Chagas’ disease. A group of 94 Chagas’ disease patients treated with benznidazole at least 10 years earlier were evaluated from the laboratory and clinical points of view. When conventional serology (enzyme- linked immunosorbent assay [ELISA], indirect immunofluorescence [IIF], and indirect hemagglutination [IHA]) and classic criteria (consistent results with any two of the three tests) or more rigorous criteria (consistent results from the three tests) were used, 10.6% and 8.5% of patients were considered treated and cured (TC) by classic and rigorous criteria, respectively. Patients were then evaluated using supplementary (recombinant ELISA and Trypanosoma cruzi excreted-secreted antigen blotting [TESA-blot]), parasitological (hemoculture), and molecular (PCR) tests. The results of recombinant ELISA were similar to those with the rigorous criterion (three consistent test results). The TESA-blot group showed a higher percentage (21.3%) of negative results than the groups defined by either cure criterion. Hemoculture and PCR gave negative results for all treated and cured (TC) patients, regardless of the criterion used. Recombinant ELISA and TESA-blot tests showed negative results for 70% and 87.5% of the patients categorized as TC by the classic and three-test criteria, respectively. For patients with discordant conventional serology, the supplementary serological and molecular tests were the decisive factor in determining therapeutic failure. Clinical evaluation showed that 62.5% of TC patients presented with the indeterminate form of the disease. Additionally, treated patients with negative TESA-blot results should be reevaluated later with all methodologies used here to verify whether TESAblot is a reliable way to determine early parasitological cure of Chagas’ disease.Item Are increased frequency of macrophage-like and natural killer (NK) cells, together with high levels of NK T and CD4+CD25high T cells balancing activated CD8+ T cells, the key to control Chagas'disease morbidity?.(2006) Avelar, Danielle Marchetti Vitelli; Avelar, Renato Sathler; Massara, Rodrigo Lima; Borges, Jaila Dias; Lage, Paula Souza; Lana, Marta de; Carvalho, Andréa Teixeira de; Dias, João Carlos Pinto; Santos, Silvana Maria Elói; Martins Filho, Olindo AssisThe immunological response during early human Trypanosoma cruzi infection is not completely understood, despite its role in driving the development of distinct clinical manifestations of chronic infection. Herein we report the results of a descriptive flow cytometric immunophenotyping investigation of major and minor peripheral blood leucocyte subpopulations in T. cruzi - infected children, characterizing the early stages of the indeterminate clinical form of Chagas’ disease. Our results indicated significant alterations by comparison with uninfected children, including increased values of pre-natural killer (NK)-cells (CD3 – CD16 + CD56 – ), and higher values of proinflammatory monocytes (CD14 + CD16 + HLA-DR ++ ). The higher values of activated B lymphocytes (CD19 + CD23 + ) contrasted with impaired T cell activation, indicated by lower values of CD4 + CD38 + and CD4 + HLA-DR + lymphocytes, a lower frequency of CD8 + CD38 + and CD8 + HLA-DR + cells; a decreased frequency of CD4 + CD25 HIGH regulatory T cells was also observed. These findings reinforce the hypothesis that simultaneous activation of innate and adaptive immunity mechanisms in addition to suppression of adaptive cellular immune response occur during early events of Chagas’ disease. Comparative cross-sectional analysis of these immunophenotypes with those exhibited by patients with late chronic indeterminate and cardiac forms of disease suggested that a shift toward high values of macrophage-like cells extended to basal levels of proinflammatory monocytes as well as high values of mature NK cells, NKT and regulatory T cells, may account for limited tissue damage during chronic infection favouring the establishment/maintenance of a lifelong indeterminate clinical form of the disease. On the other hand, development of an adaptive cell-mediated inflammatory immunoprofile characterized by high levels of activated CD8 + cells and basal levels of mature NK cells, NKT and CD4 + CD25 HIGH cells might lead to late chronic pathologies associated with chagasic heart disease.