Dynamics of Interleukin-9 Producing Lymphocytes in Strongyloides ratti-Infected Mice

TY - JOUR

T1 - Dynamics of Interleukin-9 Producing Lymphocytes in Strongyloides ratti-Infected Mice

AU - Hartmann, Wiebke

AU - Heepmann, Lennart

AU - Linnemann, Lara

AU - Licona-Limon, Paula

AU - Colomb, Florent

AU - Frangova, Tania

AU - McSorley, Henry J.

AU - Breloer, Minka

N1 - Copyright: © 2026 by the authors.

PY - 2026/3

Y1 - 2026/3

N2 - 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.

AB - 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.

KW - CD4 T cells

KW - IL-9

KW - ILC2

KW - immunosuppression

KW - Strongyloides

UR - https://www.scopus.com/pages/publications/105034076399

U2 - 10.3390/pathogens15030257

DO - 10.3390/pathogens15030257

M3 - Article

C2 - 41901710

AN - SCOPUS:105034076399

VL - 15

JO - Pathogens

JF - Pathogens

IS - 3

M1 - 257

ER -