Teses em Biologia de Agentes Infecciosos e Parasitários (Doutorado) - PPGBAIP/ICB

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/4698

O Doutorado em Biologia de Agentes Infecciosos e Parasitários teve início em 2005 e funciona no Programa de Pós-Graduação em Biologia de Agentes Infecciosos e Parasitários (PPGBAIP) do Instituto de Ciências Biológicas (ICB) da Universidade Federal do Pará (UFPA).

Navegar

Agora exibindo 1 - 1 de 1

Acesso aberto (Open Access)
Imunopatologia hepática da infecção experimental do vírus dengue em Callithrix penicillata
(Universidade Federal do Pará, 2015-09-25) HENRIQUES, Daniele Freitas; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
Dengue is one of most important public health problem in the world, and one of the factors that contribute with this situation is the lack of an effective vaccine against the disease, and in part, this difficulty to obtain is due clinical the lack of an experimental model that mimic the infection and manifestation of the disease as those observed in humans. Then, the Evandro Chagas Institute showed the presence of dengue antigens using the Immunohistochemistry assay, in the liver of a non-human primate (NHP) of the species Callithrix jacchus, with a fatal outcome following dengue hemorrhagic fever. Based in the above considerations and in addition to the fact that the liver is the targetb organ for Dengue Virus (DENV) in humans, it is important to analyze the liver of primates of the genus Callithrix in order to study the pathogenesis and the immunopathology of sequential infection by DENV. A total of 26 NHP Callithrix penicillata were submitted to primary infection (PI) subcutaneously with DENV-3 (3.23 x 103 PFU/mL), and 13 of these animals anesthetized and sacrificed daily for seven days post-infection (dpi) (acute phase) and in random intervals until 60 dpi (convalescent phase); the secondary infection (SI) with DENV-2 (4.47 x 104 PFU/mL) was performed two months after the PI in the remaining 13 animals. Uninfected sentinels animals were reserved up ending of the experiment. The liver of the animals were processed for histopathology and Immunohistochemical assay using polyclonal antibodies to DENV and antibodies for analyses of the innate and cellular immune response as well as the cytokine expression . The NHP were susceptible to sequential infection by DENV-3 and DENV-2; in the liver viral antigens were expressed in hepatocytes, Kupffer cells and Councilman bodies; the histopathological changes in liver was characterized by the presence of apoptosis, focal lytic necrosis, steatosis, swelling cellular, inflammation (acinar, EP and HCV), hyperplasia/hypertrophy in Kupffer cells, hemosiderin in Kupffer cells and sinusoidal dilatation; the intensity of the liver damage was prominent in the acute phase of PI and SI resulting in acute hepatitis. In addition the apoptosis was the most frequent mechanism of death of hepatocytes; lytic necrosis and inflammatory infiltrate showed predominant distribution pattern in Z2. An increase of the acinar expression of activated macrophages, NK cells, S-100 protein and B-lymphocytes during the stages of PI and SI; as well as, increased acinar expression of TCD4 + lymphocytes during the acute phase of PI; as to the quantification of cytokines and molecules, was observed an increase in acinar expression of: IFN- during the stages of PI and SI, TNF-α and IL-8 with higher prevalence in SI, TGF-β and IL-10 with prevalence in acute phase of PI, Fas protein during the acute phase of PI and SI and VCAM in acute phase of SI, as well as increase in expression in the EP. These findings were similar to those observed in livers from fatal cases of dengue fever in humans, but with lower intensity and amplitude, thus indicating that NHP Callithrix penicillata species is a good experimental model for infection by DENV, involving immunopathologic studies.

Navegar

Navegando Teses em Biologia de Agentes Infecciosos e Parasitários (Doutorado) - PPGBAIP/ICB por Área de Concentração "BIOLOGIA E EPIDEMIOLOGIA DE AGENTES INFECCIOSOS E PARASITÁRIOS"