Plasticity of TH17 cells in Peyer's patches is responsible for the induction of T cell-dependent IgA responses.

1] Division of Molecular Immunology, Medical Research Council National Institute for Medical Research, Mill Hill, London, UK. [2].
Nature Immunology (Impact Factor: 24.97). 03/2013; DOI: 10.1038/ni.2552
Source: PubMed

ABSTRACT Intestinal Peyer's patches are essential lymphoid organs for the generation of T cell-dependent immunoglobulin A (IgA) for gut homeostasis. Through the use of interleukin 17 (IL-17) fate-reporter mice, we found here that endogenous cells of the TH17 subset of helper T cells in lymphoid organs of naive mice 'preferentially' homed to the intestines and were maintained independently of IL-23. In Peyer's patches, such TH17 cells acquired a follicular helper T cell (TFH cell) phenotype and induced the development of IgA-producing germinal center B cells. Mice deficient in TH17 cells failed to generate antigen-specific IgA responses, which provides evidence that TH17 cells are the crucial subset required for the production of high-affinity T cell-dependent IgA.

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