title: Stat6 signaling promotes protective immunity against Trichinella spiralis through a mast cell- and T cell-dependent mechanism.
abstract: Studies in mice infected with the gastrointestinal nematode parasite Nippostrongylus brasiliensis demonstrated that IL-4/IL-13 activation of Stat6 suppresses development of intestinal mastocytosis and does not contribute to IL-4/IL-13 production, but is still essential for parasite expulsion. Because expulsion of another gastrointestinal nematode, Trichinella spiralis, unlike N. brasiliensis expulsion, is mast cell dependent, these observations suggested that T. spiralis expulsion would be Stat6 independent. Instead, we find that Stat6 activation by IL-4/IL-13 is required in T. spiralis-infected mice for the mast cell responses that induce worm expulsion and for the cytokine responses that induce intestinal mastocytosis. Furthermore, although IL-4 induces N. brasiliensis expulsion in the absence of B cells, T cells, and mast cells, mast cells and T cells are required for IL-4 induction of T. spiralis expulsion. Thus, Stat6 signaling is required for host protection against N. brasiliensis and T. spiralis but contributes to expulsion of these two worms by different mechanisms. The induction of multiple effector mechanisms by Stat6 signaling provides a way for a cytokine response induced by most gastrointestinal nematode parasites to protect against most of these parasites, even though different effector mechanisms are required for protection against different nematodes.
authors.affiliation: U.S. Department of Agriculture, Beltsville, MD, 20705, USA.
authors.forename: J F
authors.initials: JF
authors.lastname: Urban
authors.forename: L
authors.initials: L
authors.lastname: Schopf
authors.forename: S C
authors.initials: SC
authors.lastname: Morris
authors.forename: T
authors.initials: T
authors.lastname: Orekhova
authors.forename: K B
authors.initials: KB
authors.lastname: Madden
authors.forename: C J
authors.initials: CJ
authors.lastname: Betts
authors.forename: H R
authors.initials: HR
authors.lastname: Gamble
authors.forename: C
authors.initials: C
authors.lastname: Byrd
authors.forename: D
authors.initials: D
authors.lastname: Donaldson
authors.forename: K
authors.initials: K
authors.lastname: Else
authors.forename: F D
authors.initials: FD
authors.lastname: Finkelman
mesh_terms: D000818:Animals; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D007113:Immunity, Innate; D007074:Immunoglobulin G / Q000096:biosynthesis; D007371:Interferon-gamma / Q000502:physiology; D018793:Interleukin-13 / Q000502:physiology; D015847:Interleukin-4 / Q000502:physiology; D008297:Male; D008407:Mast Cells / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D008819:Mice, Nude; D019948:Receptors, Interleukin-4 / Q000378:metabolism; D050800:STAT6 Transcription Factor; D015398:Signal Transduction / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism; D015534:Trans-Activators / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D017160:Trichinella spiralis / Q000276:immunology* / Q000502:physiology; D014235:Trichinellosis / Q000276:immunology* / Q000469:parasitology / Q000517:prevention & control
chemical_list: D016207:Cytokines; D007074:Immunoglobulin G; D018793:Interleukin-13; D019948:Receptors, Interleukin-4; D050800:STAT6 Transcription Factor; C494100:Stat6 protein, mouse; D015534:Trans-Activators; D015847:Interleukin-4; D007371:Interferon-gamma