Fasciola hepatica induces Foxp3 T cell, proinflammatory and regulatory cytokine overexpression in liver from infected sheep during early stages of infection

AbstractThe expression of T regulatory cells (Foxp3), regulatory (interleukin [IL]-10 and transforming growth factor beta [TGF- β]) and proinflammatory (tumor necrosis factor alpha [TNF-α] and interleukin [IL]-1β) cytokines was quantified using real time polymerase chain reaction (qRT-PCR) in the liver of sheep during early stages of infection withFasciola 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 fromF. hepatica (FhCL1) in Montanide adjuvant and infected; (b) group 2 was uniquely infected withF. 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-β gene expression. The expression of proinflammatory cytokines increased gra...
Source: Veterinary Research - Category: Veterinary Research Source Type: research