Natural killer T cells contribute to airway eosinophilic inflammation induced by ragweed through enhanced IL-4 and eotaxin production

Authors

  • Laura Bilenki,

    1. Department of Immunology, Immune Regulation of Allergy Research Group, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
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  • Jie Yang,

    1. Department of Medical Microbiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
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  • Yijun Fan,

    1. Department of Medical Microbiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
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  • Shuhe Wang,

    1. Department of Medical Microbiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
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  • Xi Yang

    Corresponding author
    1. Department of Immunology, Immune Regulation of Allergy Research Group, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
    2. Department of Medical Microbiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
    • Department of Medical Microbiology, Faculty of Medicine, University of Manitoba, Room 523, 730 William Avenue, Winnipeg, Manitoba, Canada R3E 0W3 Fax: +1-204-789-3926
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Abstract

Although NKT cells have been found to be capable of modulating immune responses in several model systems, the role of NKT cells in allergy remains unclear. Using CD1 gene knockout (KO) mice, which lack NKT cells, we examined the function of NKT cells in the development of allergic inflammation induced by a common airborne human allergen, ragweed. The data showed that airway eosinophilia and mucus overproduction induced by ragweed were significantly reduced in CD1 KO mice, which was correlated with significantly lower allergen-driven IL-4 production and lower eotaxin responses in the airways of CD1 KO mice. Moreover, both ragweed-specific and total serum IgE levels in CD1 KO mice were significantly lower than those in control BALB/c mice. The reduced allergic reaction in CD1 KO mice is not due to intrinsic deficiency because they showed normal levels of immune cells and function. In addition, in vivo stimulation of NKT cells using their natural ligand, α-galactosylceramide, enhanced ragweed-induced airway eosinophilia, IL-4, and eotaxin production in control, but not CD1 KO mice. These data provide in vivo evidence for the involvementof NKT cells in the allergic mechanisms responsible for allergen-driven cytokine and chemokine production and airway inflammation.

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