Pulmonary paracoccidioidomycosis (PCM) in IL-10 knock-out (KO) mice
ABCD PBi
Pulmonary paracoccidioidomycosis (PCM) in IL-10 knock-out (KO) mice
Autor:
Tânia Alves da Costa
Vera Lúcia Garcia Calich
;
Congresso do Instituto de Ciências Biomédicas (4. 2005 São Paulo)
Assuntos:
IMUNOLOGIA
É parte de:
Resumos São Paulo: Comissão de Cultura e Extensão Universitária do ICB/USP, 2005
Notas Locais:
Disponível somente em CD-ROM
Descrição:
Objective: Studies in experimental PCM have demonstrated that immunological resistance is linked to a preferential Th1 immune response whereas susceptibility is associated with absence or low levels of IFN-gamma. Patients with the severe and mild forms of the disease as well as susceptible and resistant mice to PCM secrete IL-10 throughout the course of the disease but its precocious or enhanced synthesis appear to be associated with the most severe aspects of the infection. To better understand the in vivo role of IL-10, pulmonary PCM was comparatively studied in IL-10 KO mice and their normal counterparts of the C57BL/6 strain. Methods and Results: Wild type (WT) (n=5-8) and IL-10 KO male mice (n=5-8) were i.t. infected with 1x106 yeast cells of P. brasiliensis. Mice were sacrificed 8 weeks after infection and the severity of disease determined by organ CFU counts and lungs histopathology. Pulmonary cytokines and levels of specific isotypes were evaluated by ELISA in lung homogenates or serum samples, respectively. At 8 week after infection, IL-10 KO mice presented decreased fungal loads in the lungs (KO 3.43±0.18; WT 5.15±0.15 log10) and no fungal cells were detected in the livers and spleens. Lung histology revealed the presence of numerous granulomatous lesions in control mice whereas KO animals presented almost no fungal cells and lesions indicating an evident tendency to cure. The much less severe disease of IL-10 KO mice was accompanied by low
levels of IgG2a (KO 2.24±1.10; WT 10.69±0.53 log2), IgG2b (KO 6.57±0.41; WT 10.75±0.68 log2) and IgG3 (KO 1.99±0.97; WT 5.32±0 log2) and decreased amounts of pulmonary IL-12 (KO 167.25±34; WT 305.63±41 pg/ml). Conclusion: Genetically determined deficiency of IL-10 results in a less severe PCM which appears to evolve to microbiological cure. Interestingly, this picture was not concomitant with a decreased Th2 immunity but was associated with a diminished Th1 immunity
Editor:
São Paulo Comissão de Cultura e Extensão Universitária do ICB/USP
Data de criação/publicação:
2005
Formato:
[s. p.].
Idioma:
Inglês