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Development and evolution of RORγt+ cells in a microbe's world
1Lymphoid Tissue Development Unit, Institut Pasteur, Paris, France. CNRS, URA1961, Paris, France. gerard.eberl@pasteur.fr
Immunological Reviews
|December 16, 2011
Summary
Retinoid-related orphan receptor γt (RORγt) drives inflammation in immune cells, producing key cytokines. RORγt(+) cells are crucial for developing immune organs and maintaining gut health with microbes.
Area of Science:
- Immunology
- Molecular Biology
- Developmental Biology
Background:
- Retinoid-related orphan receptor γt (RORγt) is a nuclear hormone receptor.
- RORγt orchestrates a pro-inflammatory program in lymphoid cells, including IL-6, IL-17, IL-22, GM-CSF, and TNF production.
Purpose of the Study:
- To investigate the role of RORγt in immune cell development and function.
- To understand the involvement of RORγt(+) cells in host-microbe interactions and tissue homeostasis.
Main Methods:
- Analysis of RORγt expression during immune cell ontogeny.
- Characterization of RORγt(+) innate lymphoid cells (ILCs) and T cells.
Main Results:
- RORγt is first expressed in lymphoid tissue inducer cells during fetal development, essential for lymph node and Peyer's patch formation.
- Postnatally, RORγt(+) ILCs and T cells defend epithelial surfaces against microbes.
- These cells are vital for maintaining intestinal homeostasis with symbiotic microbiota.
Conclusions:
- RORγt plays a critical role in immune system development and inflammatory responses.
- RORγt(+) cells are key players in establishing and maintaining the host-microbe interface, particularly in the gut.
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