Global gene expression analysis of the zoonotic parasite Trichinella spiralis revealed novel genes in host parasite interaction
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ABSTRACT: Trichinellosis of human and other mammals was caused through the ingestion of the parasite,Trichinella spiralis,contaminated meat. It is a typical zoonotic disease that affects more than 10 million people world-wide. Parasites of Trichinella genus are unique intracellular pathogens. Adult Trichinella parasites directly release newborn larvae which invade striated muscle cells and causes diseases. In this study, we profiled the global transcriptome in the three developmental stages of T. spiralis. The transcriptomic analysis revealed the global gene expression patterns from newborn larval stage through muscle larval stage to adults. Thousands of genes with stage-specific transcriptional patterns were described and novel genes involving host-parasite interaction were identified. More than 45% of the protein-coding genes showed evidence of transcription from both sense and antisense strands which suggests the importance of RNA-mediated gene regulation in the parasite. This study presents a first deep analysis of the transcriptome of T. spiralis, providing insight information of the parasite biology.
Project description:Trichinellosis of human and other mammals was caused through the ingestion of the parasiteM-oM-<M-^LTrichinella spiralisM-oM-<M-^Lcontaminated meat. It is a typical zoonotic disease that affects more than 10 million people world-wide. Parasites of Trichinella genus are unique intracellular pathogens. Adult Trichinella parasites directly release newborn larvae which invade striated muscle cells and causes diseases. In this study, we profiled the global transcriptome in the three developmental stages of T. spiralis. The transcriptomic analysis revealed the global gene expression patterns from newborn larval stage through muscle larval stage to adults. Thousands of genes with stage-specific transcriptional patterns were described and novel genes involving host-parasite interaction were identified. More than 45% of the protein-coding genes showed evidence of transcription from both sense and antisense strands which suggests the importance of RNA-mediated gene regulation in the parasite. This study presents a first deep analysis of the transcriptome of T. spiralis, providing insight information of the parasite biology. Messenger RNA from three developmental stages of T. spiralis was selectively purified from total RNA using oligo-(dT) conjugated magnetic beads. Complementary DNA (cDNA) was synthesized guided by oligo-(dT) as a primer.
Project description:This project aimed to explore novel anticancer therapeutics from products of parasite since several data related to benefits from the T. spiralis infection have been documented. We validated antitumor activity of T. spiralis infective larval extract and extricate the parasite-derived-antitumor peptide. We found that larval extract exerted antitumor activity to three types of carcinoma cells including hepatocellular carcinoma HepG2, ovarian cancer SK-OV-3, and lung adenocarcinoma A549. Interestingly, it displayed the most antitumor effect to HepG2 cells. Using proteomic and bioinformatic approaches, three putative anticancer peptides were identified from T. spiralis infective larval extract. One of these peptides showed a dose-dependent-anti-HepG2 effect by inducing ROS accumulation, leading to inhibition of the cell proliferation. Our data indicate potential application of the larval extract-derived antitumor peptide as a complementary agent for human hepatoma treatment and highlight a positive aspect of parasite apart from its deleterious effect.
Project description:We present the first study to confirm the existence of DNA methylation in the parasitic nematode Trichinella spiralis, and we characterize the methylomes of the three life-cycle stages of this food-borne infectious human pathogen. We observe a drastic increase in DNA methylation during the transition from the new born to mature stage, and we further identify parasitism-related genes that show changes in DNA methylation status between life cycle stages. We also evaluated differential gene expression among the three life stages using Illumina HiSeq 2000 RNA-seq technology.
Project description:We describe the first comprehensive study confirming the existence of DNA methylation, characterising the methylomes of three life stages of the food-borne agent of human trichinellosis, Trichinella spiralis. We further identify sets of genes where the DNA methylation status varied between thedevelopmental stages that are closely related to the parasitism of the organism. Examination of DNA methylation status in three life stages (Adult, muscle larve, new born larve) of Trchinella Spiralis using MethylC-seq.
Project description:It has become increasingly clear in recent years that the function for eosinophils in health and disease is highly varied. Recent studies have revealed novel functions for eosinophils in metabolism and tissue regeneration. Such mechanisms have strong potential to be relevant in worm infections in which parasites rely on host metabolism for nutrients that support worm growth or reproduction. The aim of this study was to investigate the mechanism underlying the observation that eosinophils promote growth of Trichinella spiralis larvae in skeletal muscle. Our results indicate that normal larval growth requires IL-4 and STAT6 signaling that are intrinsic to eosinophils. Support of growth by eosinophil-derived IL-4 occurs independently of adaptive immunity. Host gene expression in skeletal muscle was compatible with a regenerative response to invasion by newborn larvae and a shift in the source of energy in infected tissue. Furthermore, the presence of eosinophils suppressed local inflammation while also influencing nutrient homeostasis in muscle. Redistribution of glucose transporter 4 (GLUT4) and phosphorylation of Akt were observed in nurse cells, compatible with enhancement of glucose uptake and storage of glycogen by larvae that is known to occur. The results suggest that eosinophil-derived IL-4 may promote larval growth by altering nutrient metabolism in infected muscle. Our findings document a novel interaction between worms and host, in which worms have evolved a strategy to co-opt an innate host cell response in a way that facilitates their growth. Whole diaphragms from WT, Rag1-/- and PHIL mice were harvested at 0, 2 and 7 days post-infection of mice with 25,000 Trichinella spiralis newborn larvae (administered retro-orbitally) and preserved in RNAlater (Qiagen). Two to three replicate mice were used for each condition.
Project description:The gut microbiota plays an important role in parasite-host interactions and the induction of immune defense responses. Trichinella spiralis is an important zoonotic parasite that can directly or indirectly interact with the host in the gut. Changes in the gut microbiota following infection with T. spiralis and the role of the gut microbiota in host immune defense against T. spiralis infection were investigated in our study. 16S rRNA sequencing analysis revealed that infection with T. spiralis can reduce the diversity of the gut microbiota and alter the structure of the gut microbiota during early infection, which was restored when the worm left the gut. Antibiotic treatment (ABX) and fecal bacterial transplantation (FMT) were used to investigate the role of the gut microbiota in the host expulsion response during infection with T. spiralis. We found that ABX mice had a higher burden of parasites, and the burden of parasites decreased after fecal bacterial transplantation. The results of flow cytometry and qPCR revealed that the disturbance of the gut microbiota affects the proportion of CD4+ T cells and the production of IL-4, which weakens Th2 responses and makes expulsion difficult. In addition, as the inflammatory response decreased with the change of the microbiota, the Th1 response also decreased. The metabolomic results were in good agreement with these findings, as the levels of inflammatory metabolites such as ceramides were reduced in the ABX group. In general, T. spiralis infection can cause changes in the gut microbiota, and the presence or absence of microbes may also weaken intestinal inflammation and the expulsion of T. spiralis by affecting the immune response of the host.