Dataset Information

Hookworm-Derived Metabolites Suppress Pathology in a Mouse Model of Colitis and Inhibit Secretion of Key Inflammatory Cytokines in Primary Human Leukocytes.

ABSTRACT: Iatrogenic hookworm therapy shows promise for treating disorders that result from a dysregulated immune system, including inflammatory bowel disease (IBD). Using a murine model of trinitrobenzenesulfonic acid-induced colitis and human peripheral blood mononuclear cells, we demonstrated that low-molecular-weight metabolites derived from both somatic extracts (LMWM-SE) and excretory-secretory products (LMWM-ESP) of the hookworm, Ancylostoma caninum, display anti-inflammatory properties. Administration to mice of LMWM-ESP as well as sequentially extracted fractions of LMWM-SE using both methanol (SE-MeOH) and hexane-dichloromethane-acetonitrile (SE-HDA) resulted in significant protection against T cell-mediated immunopathology, clinical signs of colitis, and impaired histological colon architecture. To assess bioactivity in human cells, we stimulated primary human leukocytes with lipopolysaccharide in the presence of hookworm extracts and showed that SE-HDA suppressed ex vivo production of inflammatory cytokines. Gas chromatography-mass spectrometry (MS) and liquid chromatography-MS analyses revealed the presence of 46 polar metabolites, 22 fatty acids, and five short-chain fatty acids (SCFAs) in the LMWM-SE fraction and 29 polar metabolites, 13 fatty acids, and six SCFAs in the LMWM-ESP fraction. Several of these small metabolites, notably the SCFAs, have been previously reported to have anti-inflammatory properties in various disease settings, including IBD. This is the first report showing that hookworms secrete small molecules with both ex vivo and in vivo anti-inflammatory bioactivity, and this warrants further exploration as a novel approach to the development of anti-inflammatory drugs inspired by coevolution of gut-dwelling hookworms with their vertebrate hosts.

SUBMITTER: Wangchuk P

PROVIDER: S-EPMC6434117 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Background & aimsAfter allogeneic transplantation, murine stem cells (SCs) for interstitial cells of Cajal (ICCs), electrical pacemaker, and neuromodulator cells of the gut, were incorporated into gastric ICC networks, indicating in vivo immunosuppression. Immunosuppression is characteristic of bone marrow- and other non-gut-derived mesenchymal stem cells (MSCs), which are emerging as potential therapeutic agents against autoimmune diseases, including inflammatory bowel disease. Therefore, we investigated whether gut-derived ICC-SCs could also mitigate experimental colitis and studied the mechanisms of ICC-SC-mediated immunosuppression in relation to MSC-induced pathways.MethodsIsolated ICC-SCs were studied by transcriptome profiling, cytokine assays, flow cytometry, mixed lymphocyte reaction, and T-cell proliferation assay. Mice with acute and chronic colitis induced by dextran sulfate sodium and T-cell transfer, respectively, were administered ICC-SCs intraperitoneally and evaluated for disease activity by clinical and pathological assessment and for ICC-SC homing by live imaging.ResultsUnlike strain-matched dermal fibroblasts, intraperitoneally administered ICC-SCs preferentially homed to the colon and reduced the severity of both acute and chronic colitis assessed by clinical and blind pathological scoring. ICC-SCs profoundly suppressed T-cell proliferation in vitro. Similar to MSCs, ICC-SCs strongly expressed cyclooxygenase 1/2 and basally secreted prostaglandin E2. Indomethacin, a cyclooxygenase inhibitor, countered the ICC-SC-mediated suppression of T-cell proliferation. In contrast, we found no role for regulatory T-cell-, programmed death receptor-, and transforming growth factor-β-mediated mechanisms reported in MSCs; and transcriptome profiling did not support a relationship between ICC-SCs and MSCs.ConclusionsMurine ICC-SCs belong to a class different from MSCs and potently mitigate experimental colitis via prostaglandin E2-mediated immunosuppression.

Project description:Gastrointestinal (GI) parasites, hookworms in particular, have evolved to cause minimal harm to their hosts, allowing them to establish chronic infections. This is mediated by creating an immunoregulatory environment. Indeed, hookworms are such potent suppressors of inflammation that they have been used in clinical trials to treat inflammatory bowel diseases (IBD) and celiac disease. Since the recent description of helminths (worms) secreting extracellular vesicles (EVs), exosome-like EVs from different helminths have been characterized and their salient roles in parasite-host interactions have been highlighted. Here, we analyze EVs from the rodent parasite Nippostrongylus brasiliensis, which has been used as a model for human hookworm infection. N. brasiliensis EVs (Nb-EVs) are actively internalized by mouse gut organoids, indicating a role in driving parasitism. We used proteomics and RNA-Seq to profile the molecular composition of Nb-EVs. We identified 81 proteins, including proteins frequently present in exosomes (like tetraspanin, enolase, 14-3-3 protein, and heat shock proteins), and 27 sperm-coating protein-like extracellular proteins. RNA-Seq analysis revealed 52 miRNA species, many of which putatively map to mouse genes involved in regulation of inflammation. To determine whether GI nematode EVs had immunomodulatory properties, we assessed their potential to suppress GI inflammation in a mouse model of inducible chemical colitis. EVs from N. brasiliensis but not those from the whipworm Trichuris muris or control vesicles from grapes protected against colitic inflammation in the gut of mice that received a single intraperitoneal injection of EVs. Key cytokines associated with colitic pathology (IL-6, IL-1β, IFNγ, and IL-17a) were significantly suppressed in colon tissues from EV-treated mice. By contrast, high levels of the anti-inflammatory cytokine IL-10 were detected in Nb-EV-treated mice. Proteins and miRNAs contained within helminth EVs hold great potential application in development of drugs to treat helminth infections as well as chronic non-infectious diseases resulting from a dysregulated immune system, such as IBD.

Dataset Information

Hookworm-Derived Metabolites Suppress Pathology in a Mouse Model of Colitis and Inhibit Secretion of Key Inflammatory Cytokines in Primary Human Leukocytes.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets