{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T15:28:42Z","timestamp":1772465322085,"version":"3.50.1"},"reference-count":43,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T00:00:00Z","timestamp":1772236800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German research association DFG","award":["BR 3754\/10-1"],"award-info":[{"award-number":["BR 3754\/10-1"]}]},{"name":"German research association DFG","award":["BR 3754\/6-1"],"award-info":[{"award-number":["BR 3754\/6-1"]}]},{"name":"Wellcome Investigator award","award":["221914\/Z\/20\/Z"],"award-info":[{"award-number":["221914\/Z\/20\/Z"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Helminths infect a quarter of the human population and are controlled in the frame of a canonical type-2 immune response. Interleukin-9 is a cytokine with pleiotropic functions during type-2 immunity that can be produced by many different cells. Accumulating evidence suggest that IL-9 is of particular relevance in controlling intestinal helminth infections. Using mice infected with the parasitic nematode Strongyloides ratti, we showed previously that ejection from the intestine depends on IL-9 and IL-9-mediated activation of mucosal mast cells. Here we use IL-9 reporter mice to identify the relevant cellular sources of IL-9 in vivo. We report that predominantly CD4+ T cells and group 2 innate lymphoid cells (ILC2s) produced IL-9 in S. ratti-infected or IL-33-treated mice. Interestingly, the IL-33-mediated induction of IL-9 and subsequent mast cell degranulation was modulated by concurrent S. ratti infection. While the IL-33-mediated expansion of IL-9-producing ILC2s was supressed by S. ratti infection, IL-9-producing CD4+ T cells were proportionally increased. Finally, we show that S. ratti-derived E\/S products interfered with IL-9 production by BM-derived ILC2 in vitro. In conclusion, we have identified that ILC2 and CD4+ T cells produce IL-9 during S. ratti infection, and that ILC2 responses are suppressed by S. ratti products.<\/jats:p>","DOI":"10.3390\/pathogens15030257","type":"journal-article","created":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T14:06:56Z","timestamp":1772460416000},"page":"257","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Dynamics of Interleukin-9 Producing Lymphocytes in Strongyloides ratti-Infected Mice"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4998-0586","authenticated-orcid":false,"given":"Wiebke","family":"Hartmann","sequence":"first","affiliation":[{"name":"Helminth Immunology, Section Interface, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lennart","family":"Heepmann","sequence":"additional","affiliation":[{"name":"Helminth Immunology, Section Interface, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4963-2888","authenticated-orcid":false,"given":"Lara","family":"Linnemann","sequence":"additional","affiliation":[{"name":"Helminth Immunology, Section Interface, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paula","family":"Licona-Limon","sequence":"additional","affiliation":[{"name":"Departamento de Biolog\u00eda Celular y del Desarrollo, Instituto de Fisiolog\u00eda Celular, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Mexico City 04510, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Florent","family":"Colomb","sequence":"additional","affiliation":[{"name":"Faculty of Life Sciences, University of Dundee, Dundee DD1 5EH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tania","family":"Frangova","sequence":"additional","affiliation":[{"name":"Faculty of Life Sciences, University of Dundee, Dundee DD1 5EH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Henry J.","family":"McSorley","sequence":"additional","affiliation":[{"name":"Faculty of Life Sciences, University of Dundee, Dundee DD1 5EH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6199-4908","authenticated-orcid":false,"given":"Minka","family":"Breloer","sequence":"additional","affiliation":[{"name":"Helminth Immunology, Section Interface, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany"},{"name":"Department of Biology, University Hamburg, 22609 Hamburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"252","DOI":"10.1016\/S0140-6736(17)31930-X","article-title":"Soil-transmitted helminth infections","volume":"391","author":"Jourdan","year":"2017","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Buonfrate, D., Bisanzio, D., Giorli, G., Odermatt, P., Furst, T., Greenaway, C., French, M., Reithinger, R., Gobbi, F., and Montresor, A. 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