1. Recirculating Foxp3+ regulatory T cells are restimulated in the thymus under Aire control
- Author
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Jonathan Charaix, Alexia Borelli, Jérémy C. Santamaria, Lionel Chasson, Matthieu Giraud, Arnauld Sergé, Magali Irla, Centre d'Immunologie de Marseille - Luminy (CIML), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche en Transplantation et Immunologie - Center for Research in Transplantation and Translational Immunology (U1064 Inserm - CR2TI), Institut National de la Santé et de la Recherche Médicale (INSERM)-Nantes Université - UFR de Médecine et des Techniques Médicales (Nantes Univ - UFR MEDECINE), Nantes Université - pôle Santé, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Santé, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Adhésion et Inflammation (LAI), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), ANR-19-CE18-0021,RANKLthym,Évaluer le potentiel de RANK ligand pour rétablir des fonctions thymiques efficaces après greffe de moelle osseuse et vieillissement(2019), and ANR-10-INBS-0009,France-Génomique,Organisation et montée en puissance d'une Infrastructure Nationale de Génomique(2010)
- Subjects
Pharmacology ,Cellular and Molecular Neuroscience ,[SDV]Life Sciences [q-bio] ,Autoimmune regulator ,Molecular Medicine ,Medullary thymic epithelial cells ,Autoimmunity ,Cell Biology ,Foxp3+ regulatory T cells ,Molecular Biology ,Thymus - Abstract
International audience; Thymically-derived Foxp3+ regulatory T cells (Treg) critically control immunological tolerance. These cells are generated in the medulla through high affinity interactions with medullary thymic epithelial cells (mTEC) expressing the Autoimmune regulator (Aire). Recent advances have revealed that thymic Treg contain not only developing but also recirculating cells from the periphery. Although Aire is implicated in the generation of Foxp3+ Treg, its role in the biology of recirculating Treg remains elusive. Here, we show that Aire regulates the suppressive signature of recirculating Treg independently of the remodeling of the medullary 3D organization throughout life where Treg reside. Accordingly, the adoptive transfer of peripheral Foxp3+ Treg in AireKO recipients led to an impaired suppressive signature upon their entry into the thymus. Furthermore, recirculating Treg from AireKO mice failed to attenuate the severity of multiorgan autoimmunity, demonstrating that their suppressive function is altered. Using bone marrow chimeras, we reveal that mTEC-specific expression of Aire controls the suppressive signature of recirculating Treg. Finally, mature mTEC lacking Aire were inefficient in stimulating peripheral Treg both in polyclonal and antigen-specific co-culture assays. Overall, this study demonstrates that Aire confers to mTEC the ability to restimulate recirculating Treg, unravelling a novel function for this master regulator in Treg biology.
- Published
- 2022