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Interdisciplinary collaboration is essential to overcome complex problems in contemporaneity. Chagas disease challenges in Brazilian Amazon, implicates One Health interdisciplinary approaches and teams to integrate health of humans, animals and the environment, to foster earlier detection of this zoonotic disease and better prevention. We studied the interdisciplinary team, the logistic of its long term field work and the education processes emerging on a non-formal education environment of a Chagas disease Protocol conduced in Pará. An alarming situation: notified acute cases almost doubled in two years. Photographs were presented (iconographic approach) to qualitatively describe the experience of the interdisciplinary team. Five recommendations were proposed at the end of the study. Our observational study with the interdisciplinary team confirmed the conception that “in connecting the purity of science with the pragmatism of policy, the intangibles of trust, rapport, and even friendship can be more potent than logic and more compelling than evidence”. Interdisciplinary collaboration is essential to overcome complex problems in contemporaneity. Chagas disease challenges in Brazilian Amazon, implicates One Health interdisciplinary approaches and teams to integrate health of humans, animals and the environment, to foster earlier detection of this zoonotic disease and better prevention. We studied the interdisciplinary team, the logistic of its long term field work and the education processes emerging on a non-formal education environment of a Chagas disease Protocol conduced in Pará. An alarming situation: notified acute cases almost doubled in two years. Photographs were presented (iconographic approach) to qualitatively describe the experience of the interdisciplinary team. Five recommendations were proposed at the end of the study. Our observational study with the interdisciplinary team confirmed the conception that “in connecting the purity of science with the pragmatism of policy, the intangibles of trust, rapport, and even friendship can be more potent than logic and more compelling than evidence”.

Gap junction connexin-43 (Cx43) molecules are responsible for electrical impulse conduction in the heart and are affected by transforming growth factor-beta (TGF-beta). This cytokine increases during Trypanosoma cruzi infection, modulating fibrosis and the parasite cell cycle. We studied Cx43 expression in cardiomyocytes exposed or not to TGF-beta T. cruzi, or SB-431542, an inhibitor of TGF-beta receptor type I (ALK-5). Cx43 expression was also examined in hearts with dilated cardiopathy from chronic Chagas disease patients, in which TGF-beta signalling had been shown previously to be highly activated. We demonstrated that TGF-beta treatment induced disorganised gap junctions in non-infected cardiomyocytes, leading to a punctate, diffuse and non-uniform Cx43 staining. A similar pattern was detected in T. cruzi-infected cardiomyocytes concomitant with high TGF-beta secretion. Both results were reversed if the cells were incubated with SB-431542. Similar tests were performed using human chronic chagasic patients and we confirmed a down-regulation of Cx43 expression, an altered distribution of plaques in the heart and a significant reduction in the number and length of Cx43 plaques, which correlated negatively with cardiomegaly. We conclude that elevated TGF-beta levels during T. cruzi infection promote heart fibrosis and disorganise gap junctions, possibly contributing to abnormal impulse conduction and arrhythmia that characterise severe cardiopathy in Chagas disease.

Alterations in the extracellular matrix have been observed in the cardiomyopathy of Chagas disease caused by Trypanosoma cruz i infection. However, the mechanism of extracellular matrix regulation in T. cruzi -infected cultured cardiomyocytes (CMs) is unclear. Using confocal laser microscopy, we demonstrated that treatment of these cultures with transforming growth factor beta (TGF- β ) and tumor necrosis factor alpha (TNF- α ) leads to an enhancement of the fibronectin matrix only in uninfected CMs, while infected myocytes displayed low fibronectin expression. Digital image analysis also revealed low superposition of the fibronectin signal with parasite nests in cytokine treated and untreated cultures. Cytochalasin D treatment resulted in microfilament disarray that induced a disturbance in the fibronectin network of CMs, suggesting that cytoskeleton disruption caused by T. cruzi infection disorganizes the fibronectin matrix. Western blot analysis revealed a 2-fold increase in the fibronectin expression in CM cultures after cytokine treatment, whereas T. cruzi infection significantly reduced fibronectin levels in all conditions. In contrast, no change in the laminin expression was detected after cytokine treatment. Laminin distribution was altered in T. cruzi -infected CMs, with intense laminin labeling only at the cell periphery even after cytokine treatment. Our observations indicate that TGF- β and TNF- α stimulates fibronectin expression only in uninfected cells of the T. cruzi -infected cultures, whereas the cells harboring the parasites display low or no fibronectin fibrils.

Fas/Fas ligand (Fas-L) engagement, a potent inducer of apoptosis, is also important for cellular activation, regulation of effector and chemotactic activity, and secretion of chemokines and cytokines. We evaluated the relevance of Fas/Fas-L in the regulation of myocarditis induced by Trypanosoma cruzi infection and observed that in Fas-L(-/-) mice (gld/gld), cardiac infiltration was significantly reduced, accordingly showing less cardiomyocyte destruction. Fluorescence-activated cell sorting analysis of cardiac inflammatory cells showed higher numbers of CD8(+) T cells in BALB/c compared with gld/gld mice but similar levels of lymphocyte function-associated antigen-1, intercellular adhesion molecule, CD2, and CD69 expression; MAC-1(+) myeloid cells and mast cells were increased in BALB/c mice, whereas gld/gld mice exhibited an enrichment of CD4(+/low) T cells. Intracellular labeling of cytokines revealed no clear cardiac skewing of Th1 or Th2 responses, but we found a higher number of interleukin-10(+) cells in gld/gld mice and a deficient expression of vascular cell adhesion molecule-1 on cardiac endothelial cells in gld/gld mice. Finally, we found a population of CD3(+) but CD4/CD8 double negative cardiac T cells in both groups of infected mice, but down-regulation of some adhesion molecules and surface receptors was only observed in gld/gld mice, indicating a targeted T-cell population mostly affected by the lack of Fas-L engagement. These results point to a role for myocarditis regulation by Fas/Fas-L beyond its possible direct relevance in cellular death.

In the acute phase of Trypanosoma cruzi infection, there is dramatic atrophy of the thymus. However, the pathways involved in this change have not yet been identified. This event is mainly characterized by a massive loss of cortical CD4+/CD8+ double-positive cells, but also by other structural and functional alterations in the organ. A number of molecules, including extracellular ATP, have been suggested to play a role in the selective processes that take place in the thymus. ATP and analogues trigger many different cellular responses in thymocytes and other cell types, such as the opening of plasma membrane cation channels and a pore that may induce cell death. Herein, we investigated the possible involvement of extracellular ATP in thymus atrophy induced by infection with T. cruzi. We observed that ATP induces an increase in plasma membrane permeabilization and cellular death in CD4+/CD8+ double-positive thymocytes collected from infected mice during the atrophy phase. No differences were observed prior to the atrophy phase or during the chronic phase. Our results indicate that P2Z/P2X7 receptors may play a central role in thymus atrophy during T. cruzi infection.

We performed a cross-sectional flow cytometric analysis of peripheral blood mononuclear cells to evaluate human immunologic status during early stages of Trypanosoma cruzi infection in children. We identified major immunological features corresponding to three proposed phases of disease: early acute (EA) phase, late acute (LA) phase and recent chronic (RC) phase. EA phase was accompanied by expansion of conventional B cells, up-regulation of CD54 on monocytes and down-regulation of CD54 on T cells and not associated with monocyte-activation phenotypes or changes of natural killer (NK) population. LA phase was characterized by a selective increase in a distinct lineage of NK cells (CD16+CD56-), as well as a persistent expansion of B cells and down-regulation of CD54 on T cells. RC phase showed persistent low levels of CD54 molecule on T cells and an increase of B cells, mainly triggered by expansion of the B1-cell subset, as well as increased expression of human leucocyte antigen (HLA-DR) by monocytes. These findings reinforce the hypothesis that T. cruzi-derived antigens are able to activate NK cells before the development of T-cell-mediated immunity. Moreover, our data support previous findings of increased levels of B1 lymphocytes during human Chagas' disease and show that this event is already present during initial stages of chronic infection.

The acute phase of Chagas' disease was classified as early, intermediate, and late based on the levels of anti-Galalpha, 3Gal IgG (Gal) and specific IgM (M) and IgG (G) anti-T. cruzi reactivity. While the early phase was M+G-Gal-, the intermediate phase was M+G-Gal+, M+G+Gal-, or M+G+Gal+, and the late phase was M-G+Gal+. This sequence of stages was consistent with our previous studies on acute-phase proteins. Analysis by the polymerase chain reaction (PCR) of parasite DNA in 65 blood samples of children living in Cochabamba, Bolivia showed a significant correlation (90.8%) between ELISA and PCR positivity. A lower correlation was observed between indirect hemagglutination, PCR (58%), and ELISA. Electrocardiographic analysis of 43 children studied by the PCR did not show any alteration typical of acute chagasic myocarditis. The PCR positivity was observed in eight samples where only Gal was increased, suggesting a very early T. cruzi infection, when specific antibodies were not yet present. By associating anti-Gal IgG with specific serology, early T. cruzi infection can be detected with greater precision. We suggest the use of anti-Gal antibody reactivity as an aid for the detection of recent T. cruzi infections, at least in endemic areas where diseases caused by other trypanosomatids do not overlap.

Trypanosoma cruzi proteinases are involved in host cell invasion in human patients and in mouse models. In mice, murine α 2 -macroglobulin (MAM) and murinoglobulin are circulating plasma proteinase inhibitors that also have important roles in inflammation and immune modulation. To define their role in experimental Chagas disease, we investigated the susceptibility to T. cruzi infection of mice that are deficient only in α2-macroglobulins (AM-KO) or in both MAM and monomeric murinoglobulin-1 (MM-KO), relative to the wild type (WT). Despite the high parasite load, parasitemia was lower in AM-KO and MM-KO mice than in WT mice. Nevertheless, we observed a significantly higher parasite load in the hearts of AM-KO and MM-KO mice, i.e., more amastigote nests and inflammatory infiltrates than in WT mice. This result demonstrates a protective role for MAM in the acute phase of murine T. cruzi infection. We further demonstrated in vitro that human α2-macroglobulins altered the trypomastigote morphology and motility in a dose-dependent way, and that also impaired T. cruzi invasion in cardiomyocytes. Finally, we demonstrated that the levels of transforming growth factor β in AM-KO mice increased significantly in the third week postinfection, concomitant with high amastigote burden and important fibrosis. Combined, these in vivo and in vitro findings demonstrate that the MAM contribute to the resistance of mice to acute myocarditis induced by experimental T. cruzi infection.

Science Education in Brazil: advances and challenges Tania C. de Araujo-Jorge and Marcus Vinicius Campos MatracaLab. of Innovations in Therapies, Education and Bioproducts, Instituto Oswaldo Cruz, Fiocruz-Rio, Brazil. In Brazil the consensus that education is essential for the growth of a development country is insufficient to cover the gap between desires, public policies and results, contrasting with countries like Korea and Japan. The international success of Brazilian experiences in social policies to reduce poverty reflects on a sustainable fall in the Gini index, but the PISA indicators for science education deserves impact measures. Besides, Education in Brazil came up among the priority claims in popular movements that exploded June 2013, leading governments and social actors to try to recover the lost time. In 2014 the Federal Congress should conclude discussions of the 2011-2020 Plan for National Education (PNE) and a National Education Conference is organized for February 2014. Science Education is essential for industry and social innovation and all the players in this scene face challenges, especially scientists. How is it possible to improve science teaching at schools? At different education grades what is the relative role for improvement of science curriculum, science teacher formation, science practices in formal and non-formal education, public communication of science, and learning-cognition-teaching mechanisms/theories? What is the role of artscience fusion in science education culture? What are de priorities for research and test and for implementation at short time? How is it possible to integrate and to articulate efforts of scientists and teachers, and insert science thinking for creativity since the initial basic education, through in middle fundamental education, and attaining biology, physics and chemical teachers in high school and university levels? These are some of the present questions in post-graduate productions and efforts in the CAPES Education Area that I presently do coordinate, and we will discuss them briefly, showing the advances and challenges to foster science education.