JC contributed reagents and materials. reverse transcriptase-PCR (RT-PCR) of fibrosis-related genes. Granuloma was detected by hematoxylin-eosin (H&E) staining and quantified. Flow cytometry was used for immune cell profiling and for detecting cytokine secretion. The abundance of the related cytokines was measured using quantitative RT-PCR. Results The livers of infection, T cells may promote liver fibrosis by recruiting CD11b+Gr-1+ cells. These findings shed new light on the pathogenesis of liver pathology in murine schistosomiasis. Infection is prevalent in over 74 countries, and nearly 200 million people are at risk [1C3]. Following infection, liver fibrosis is the major pathological manifestation of the disease. This is mainly due to the deposition of eggs in the host liver. The excretory secretory antigens produced by the eggs induce strong immune responses and inflammation, and trigger granuloma formation around the eggs, which in turn leads to the activation of hepatic stellate Butylphthalide cells (HSCs) and consequent liver fibrosis . The mechanisms of fibrosis have been studied extensively in the murine model of schistosomiasis. One major mechanism is the switching of the immune pattern from a predominant T helper cell 1 (Th1) response to a Th2-dominant response, which promotes granuloma and fibrosis formation by secreting cytokines such as interleukin (IL)-4, IL-5 and IL-13 [5C9]. As a member of the IL-17 family, IL-17A is involved in various biological processes by binding its cognate receptor, IL-17RA [10C13]. Accumulating evidence demonstrates that IL-17A is related to a variety of inflammatory and autoimmune diseases such as inflammatory bowel diseases (IBD) and multiple sclerosis [14C16]. Multiple studies have demonstrated that Th17 cells, natural killer T cells and T cells produce IL-17A [17C19]. Th17 promotes hepatic granuloma formation by secreting IL-17A [20C22]. Moreover, the absence of IL-17A signaling has been implicated in alleviating liver fibrosis in murine schistosomiasis . Multiple cell types, including macrophages, T follicular helper cells (Tfh), regulatory T cells (Treg), and dendritic cells (DC) are activated and involved in granuloma formation and in the process of fibrosis [24C28]. T cells are a subgroup of T cells that express a distinct T cell receptor (TCR) consisting of a and a chain, which allows rapid response to antigens without the requirement of major histocompatibility complex (MHC) presentation [29, 30]. T cells play pivotal roles in autoimmunity, inflammatory diseases, and tumor development [31C34]. Rabbit polyclonal to YY2.The YY1 transcription factor, also known as NF-E1 (human) and Delta or UCRBP (mouse) is ofinterest due to its diverse effects on a wide variety of target genes. YY1 is broadly expressed in awide range of cell types and contains four C-terminal zinc finger motifs of the Cys-Cys-His-Histype and an unusual set of structural motifs at its N-terminal. It binds to downstream elements inseveral vertebrate ribosomal protein genes, where it apparently acts positively to stimulatetranscription and can act either negatively or positively in the context of the immunoglobulin k 3enhancer and immunoglobulin heavy-chain E1 site as well as the P5 promoter of theadeno-associated virus. It thus appears that YY1 is a bifunctional protein, capable of functioning asan activator in some transcriptional control elements and a repressor in others. YY2, a ubiquitouslyexpressed homologue of YY1, can bind to and regulate some promoters known to be controlled byYY1. YY2 contains both transcriptional repression and activation functions, but its exact functionsare still unknown They also have important regulatory functions . Of note, they are an important regulator in liver diseases, including liver infection, non-alcoholic fatty liver disease, autoimmune hepatitis, and liver fibrosis . Although a correlation between T cell and neutrophil recruitment and liver fibrosis has been implicated , the exact mechanism underlying the regulatory role of T cells in liver fibrosis remains elusive. In the present study, we aimed to characterize the role of T cells in the early formation of granuloma and fibrosis in the livers of TCR knockout (KO) mice infected with the shaved skin of the abdomen, with 20 Butylphthalide 2 cercariae obtained from the National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Shanghai, China). Fifteen WT mice and 15 TCR KO mice were randomly divided into three groups, and were sacrificed for pathological observation at 0, 4 and 6 weeks post-infection, respectively. Sixteen WT mice and 16 KO mice were used for the survival time observation, and the survival rates in each group were evaluated. Liver pathology and measurement of aspartate aminotransferase/alanine aminotransferase (AST/ALT) levels Fresh liver samples were fixed in 10% neutral buffered formalin, then processed with routine paraffin-embedding procedures. The paraffin-embedded sections (5?m) were dewaxed and stained with hematoxylin-eosin (H&E) or Massons trichrome for analyzing granuloma or fibrosis, respectively. Granulomas around single eggs were selected to assess the levels of granuloma and fibrosis. Each stained section was examined by optical microscopy under 100 magnification with identical settings. Thirty pictures were taken of granulomas around single eggs from three sections in each tissue. The areas featuring granuloma and fibrosis surrounding a single egg were estimated using ImageJ Butylphthalide (NIH, Bethesda, MD, USA). Sera from individual infected mice were separated by centrifugation at 1000?for 10 min. ALT and AST levels were detected by Adicon Clinical Laboratories, Inc. (Shanghai, China). Isolation of liver non-parenchymal cells and spleen cells Single-cell suspension of hepatic leukocytes were prepared using a.