Analysis of the Trichuris suis excretory/secretory proteins as a function of life cycle stage and their immunomodulatory properties

Authors: LEROUX, LOUIS-PHILIPPE - McGill University - Canada; NASR, MOHAMAD - McGill University - Canada; VALANPARAMABIL, RAJESH - McGill University - Canada; TAM, MIFONG - McGill University - Canada; ROSA, BRUCE - Washington University; SICILIANI, ELIZABETH - McGill University - Canada; Hill, Dolores; Zarlenga, Dante; JARAMILLO, MARITZA - McGill University - Canada; WEINSTOCK, JOEL - Tufts Medical Center; GEARY, TIMOTHY - McGill University - Canada; STEVENSON, MARY - McGill University - Canada; Urban, Joseph; MAKEDONKA, MITREVA - Washington University; JARDIM, ARMANDO - McGill University - Canada

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/12/2018
Publication Date: 10/29/2018
Citation: Leroux, L., Nasr, M., Valanparamabil, R., Tam, M., Rosa, B.A., Siciliani, E., Hill, D.E., Zarlenga, D.S., Jaramillo, M., Weinstock, J.V., Geary, T.G., Stevenson, M.M., Urban Jr, J.F., Makedonka, M., Jardim, A. 2018. Analysis of the Trichuris suis excretory/secretory proteins as a function of life cycle stage and their immunomodulatory properties. Scientific Reports. 8:15921. https://doi.org/10.1038/s41598-018-34174-4.
DOI: https://doi.org/10.1038/s41598-018-34174-4

Interpretive Summary: The incidence of immune-mediated inflammatory disorders in industrialized or "westernized" countries has increased dramatically over the past century. This has been postulated to be due to a significant decrease in the incidence of infectious diseases due to antibiotic use, vaccination, improved hygiene, and generally better socio-economic conditions. Worm parasites (helminths) or molecules derived from these worms are being explored as therapeutic agents to treat inflammatory diseases. Clinical trials using the porcine whip worm, Trichuris suis, has gained attention as a potential therapeutic agent, and there are reports that whip worm proteins have immune modulating activity. This current report used a molecular screen of the expression of worm genes and a profiling of the proteins produced to effect the function of mouse immune cells as a screening system. The crude protein mixtures derived from the worm were separated by chemical procedures and tested for activity against these immune cells. Some of the protein targets that showed activity were genetically cloned and shown to have comparable activity supporting the immune modulating properties of theses individual molecules. This information is important to those interested in identifying specific molecules derived from worms that modulate both animal and human health, and regulate immunity and inflammation to generate more appropriate responses to infection that is not harmful.

Technical Abstract: Parasitic worms have a remarkable ability to modulate host immune responses through several mechanisms including excreted/secreted proteins (ESP), yet the exact nature of these proteins and their targets often remain elusive. Here, we performed mass spectrometry analyses of ESP (TsESP) from larval and adult stages of the pig whipworm Trichuris suis (Ts) and identified ~350 proteins. Transcriptomic analyses revealed large subsets of differentially expressed genes in the various life cycle stages of the parasite. Exposure of bone marrow-derived macrophages and dendritic cells to TsESP markedly diminished secretion of the pro-inflammatory cytokines TNF and IL-12p70. Conversely, TsESP exposure strongly induced release of the anti-inflammatory cytokine IL-10, and also induced high levels of nitric oxide (NO) and upregulated arginase activity in macrophages. Interestingly, TsESP failed to directly induce CD4+ CD25+ FoxP3+ regulatory T cells (Treg cells), while OVA-pulsed TsESP-treated dendritic cells suppressed antigen-specific OT-II CD4+ T cell proliferation. Fractionation of TsESP identified a subset of proteins that promoted anti-inflammatory functions, an activity that was recapitulated using recombinant T. suis triosephosphate isomerase (TPI) and nucleoside diphosphate kinase (NDK). Our study helps illuminate the intricate balance that is characteristic of parasite-host interactions at the immunological interface, and further establishes the principle that specific parasite-derived proteins can modulate immune cell functions.