The development of LTi cells

Institut Pasteur, Lymphoid Tissue Development Unit, Paris 75724, France.
Current opinion in immunology (Impact Factor: 10.88). 03/2012; 24(2):178-83. DOI: 10.1016/j.coi.2012.02.003
Source: PubMed

ABSTRACT Lymphoid tissue inducer (LTi) cells are programmed by the mammalian fetus to induce the development of lymph nodes and Peyer's patches. LTi cells share a pro-inflammatory profile with Th17 cells, as well as their requirement for the transcription factor RORγt. We discuss here the latest data on the fetal and post-natal development of LTi cells, and their relationship with the larger family of innate lymphoid cells (ILCs). We suggest that the re-programming of RORγt in a subset of common lymphoid progenitors allowed mammals to develop lymphoid organs before birth, whereas other vertebrates only develop such organs in response to infection or injury.

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