Navegando por CNPq "CNPQ::CIENCIAS BIOLOGICAS::IMUNOLOGIA::IMUNOQUIMICA"

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Acesso aberto (Open Access)
Ativação microglial, lesão da substância branca e expressão de Nogo-A em ratos submetidos à isquemia estriatal
(Universidade Federal do Pará, 2012-05-10) LIMA, Rafael Rodrigues; LEAL, Walace Gomes; http://lattes.cnpq.br/2085871005197072
The objective of this investigation was to evaluate the degenerative pattern of several white matter tracts after striatal ischemic injury, correlating degenerative process standards with the microglial activation and expression of Nogo-A. For this purpose, focal ischemia was induced with stereotactic injection of endothelin in striatum of adult rats, and only in the control animals injected with sterile saline. The animals were perfused 3, 7, 14 and 30 days after ischemia. The brain removed, postfixed, cryoprotected, cut into cryostat sections obtained and submitted to immunohistochemical investigation with the following antibodies: anti-GFAP (1:2000, Dako), anti-Tau-1 (1:500, Chemicon), Anti-MBP (1:100, Chemicon International), Anti-Nogo-A (1:100, Invitrogen), Anti-Iba1 (1:1000, WAKO), ED1 (1:500, Serotec) and Anti-MHC II (Abcam 1:100), besides the viewing of the damage pattern with cresyl violet. Slides are marked by different methods were evaluated qualitatively and quantitatively also some (Anti-Nogo A, anti-ED-1, anti-MHC-II and anti-tau-1), counts were carried out in the striatum and in the corpus callosum. The data were tabulated, statistically analyzed by Tukey test (p <0.05) and micrographs taken of the findings more representative. The slides were stained with cresyl violet revealed an increase in cell density by the infiltration of inflammatory cells to the ischemic area, with a significant increase on day 7. The blades immunostained for GFAP was found progressive increase of the population of astrocytes and an increase in cell volume 7 and 14 days. Oligodendrocyte pathology marked with Tau-1 had peak marking the 3rd day in the striatum and the 7th day in the corpus callosum, and loss of myelin compaction identified by MBP was better at 14, in the different treatment. The microglial activation identified by different immunoblots showed a peak on day 7, both in striatum and in the corpus callosum, but in the corpus callosum with a much smaller number compared to the striatum. The morphology of microglial underwent changes, which found the branched phenotype in control animals, as well as in early and late times after ischemia and amoeboid default / phagocytic day 7, coinciding with the largest number of activated cells. The count of Nogo-A + cells peaked at 3 days observed in the striatum, and there were no differences in the corpus callosum expression Nogo-A 3 to 14 days, only a decrease compared to 30 days. Thus, microinjections of ET-1 induced conspicuous striatal tissue loss, concomitant with progressive microglial activation, astrocytosis, loss of immunoreactivity for myelin basic protein and oligodendrocytes damage in various survival times after focal ischemia. These events affect a few SB tracts, as the corpus callosum. The establishment of the temporal evolution of these events is the neuropathological basis for future studies, in which they should handle the inflammatory response in order to minimize these tissue changes.
Acesso aberto (Open Access)
Imunopatogenia da interação entre acrófagos e/ou células de Langerhans e Lacazia loboi
(Universidade Federal do Pará, 2014-04-24) YAMANO, Suellen Sirleide Pereira; SALGADO, Claudio Guedes; http://lattes.cnpq.br/2310734509396125
Lobomycosis is a chronic, granulomatous, fungal infection of the skin and subcutaneous caused by the fungus Lacazia loboi. This mycosis occurs predominantly in Amazon region and affect all populations groups. Histologically, there is a chronic inflammatory reaction characterized by the intense fibroplastia and histiocytosis, abundant number of macrophages, multinucleated giant cells and presence of large numbers of yeast. Macrophages are phagocytic cells that participate in the recognition and response to pathogens through phagocytosis, antigen presentation to T lymphocytes and cytokine production. Langerhans cells (LC) are a group of dendritic cells (DC) derived from bone marrow, which are located mainly in the suprabasal layer of the epidermis. Studies on hostfungal interaction in Jorge Lobo's disease are scarce. Therefore, this study constitutes an important step towards a better understanding of L. loboi biology and pathogenesis, enabling in vitro culture of this organism endemic in Amazon region and study of their antigenic properties, as well as new therapeutic approaches. The objective of this study was to analyze the in vitro interaction between non-activated peritoneal macrophages and/or Langerhans cells isolated from BALB/c mice and L. loboi, calculating infection, phagocytosis and cellular fusion rates; also measuring the production of TNF, IL-4, IL-6, IL-10 and IL-12. Results showed that L. loboi is phagocytosed by macrophages but not by LC. Phagocytosis and infection rates in the interaction between macrophages and L. loboi was similar to interaction between macrophages, Langerhans cells and L. loboi at all times analyzed. The mean number of yeast cell per macrophage was almost equal among interactions and over time, with mean variation from 1.2 to 1.6 yeast/macrophages. No giant cells formation in coculture studied. No significant difference occurred in IL-4, Il-2 and IL-10 production between interactions studied. TNF levels decrease in interaction between macrophages and L. loboi while adding LC induces increased production of TNF-α, especially after 48 hours. LC negatively modulate IL-6 production by macrophage and L. loboi also inhibits this production by macrophages alone or cocultured with LC. L. loboi stimulated significantly IL-12 production by macrophages co-cultured with LC, but not for LC alone or macrophages.