PPAR-γ Agonist Alleviates Liver and Spleen Pathology via Inducing Treg Cells during Schistosoma japonicum Infection

摘要

Background. Peroxisome proliferator-activated receptor- (PPAR-) γ plays critical roles in human metabolic disorders and has recently been implicated as a regulator of cellular proliferation and inflammatory responses. Regulatory T cells (Tregs), which express high levels of PPAR-γ protein, have the ability to maintain immune tolerance to self-antigens and regulate immune response to Schistosoma infection. However, mechanisms involved in the resolution of these responses are elusive. Methods. Liver and spleen tissue samples in Schistosoma japonicum-infected mice after administration of pioglitazone (a PPAR-γ agonist) were collected. The hepatic and splenic pathologies were detected by H&E and Masson staining. The percentages of Th1/2 and Treg cells in the liver and spleen of each mouse were determined using flow cytometry. Levels of gene expression of PPAR-γ and Foxp3 in tissues or cells were determined using real-time PCR (RT-PCR). Macrophages were treated with pioglitazone in vitro or cocultured with normal purified CD4