Article

Basophils contribute to T(H)2-IgE responses in vivo via IL-4 production and presentation of peptide-MHC class II complexes to CD4+ T cells.

Department of Immunology and Medical Zoology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan.
Nature Immunology (Impact Factor: 24.97). 08/2009; 10(7):706-12. DOI: 10.1038/ni.1737
Source: PubMed

ABSTRACT Basophils express major histocompatibility complex class II, CD80 and CD86 and produce interleukin 4 (IL-4) in various conditions. Here we show that when incubated with IL-3 and antigen or complexes of antigen and immunoglobulin E (IgE), basophils internalized, processed and presented antigen as complexes of peptide and major histocompatibility complex class II and produced IL-4. Intravenous administration of ovalbumin-pulsed basophils into naive mice 'preferentially' induced the development of naive ovalbumin-specific CD4+ T cells into T helper type 2 (T(H)2) cells. Mice immunized in this way, when challenged by intravenous administration of ovalbumin, promptly produced ovalbumin-specific IgG1 and IgE. Finally, intravenous administration of IgE complexes rapidly induced T(H)2 cells only in the presence of endogenous basophils, which suggests that basophils are potent antigen-presenting cells that 'preferentially' augment T(H)2-IgE responses by capturing IgE complex.

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