RESUMEN
The expression of T regulatory cells (Foxp3), regulatory (interleukin [IL]-10 and transforming growth factor beta [TGF-ß]) and proinflammatory (tumor necrosis factor alpha [TNF-α] and interleukin [IL]-1ß) cytokines was quantified using real time polymerase chain reaction (qRT-PCR) in the liver of sheep during early stages of infection with Fasciola hepatica (1, 3, 9, and 18 days post-infection [dpi]). Portal fibrosis was also evaluated by Masson's trichrome stain as well as the number of Foxp3+ cells by immunohistochemistry. Animals were divided into three groups: (a) group 1 was immunized with recombinant cathepsin L1 from F. hepatica (FhCL1) in Montanide adjuvant and infected; (b) group 2 was uniquely infected with F. hepatica; and (c) group 3 was the control group, unimmunized and uninfected. An overexpression of regulatory cytokines of groups 1 and 2 was found in all time points tested in comparison with group 3, particularly at 18 dpi. A significant increase of the number of Foxp3+ lymphocytes in groups 1 and 2 was found at 9 and 18 dpi relative to group 3. A progressive increase in portal fibrosis was found in groups 1 and 2 in comparison with group 3. In this regard, group 1 showed smaller areas of fibrosis than group 2. There was a significant positive correlation between Foxp3 and IL-10 expression (by immunohistochemistry and qRT-PCR) just as between portal fibrosis and TGF-ß gene expression. The expression of proinflammatory cytokines increased gradually during the experience. These findings suggest the induction of a regulatory phenotype by the parasite that would allow its survival at early stages of the disease when it is more vulnerable.
Asunto(s)
Citocinas/genética , Fasciola hepatica/fisiología , Fascioliasis/veterinaria , Factores de Transcripción Forkhead/genética , Expresión Génica , Enfermedades de las Ovejas/inmunología , Animales , Citocinas/metabolismo , Fascioliasis/inmunología , Fascioliasis/virología , Factores de Transcripción Forkhead/metabolismo , Hígado/parasitología , Ovinos , Enfermedades de las Ovejas/virologíaRESUMEN
Immunologic response to acute hepatitis C is mainly a Th1 response, whereas fasciolopsiasis is associated with a diverse T-cell response. Interferon-alpha has immunomodulatory effects and enhances Th1 immune response. Fasciola infection could theoretically interfere with the Th1 immune response, even when acquired after an initial response to interferon-alpha treatment for acute hepatitis C virus (HCV) infection. We report here the case of a male patient who acquired Fasciola hepatica infection after an initial response to IFN-alpha therapy with a favorable outcome.