Characterization of the thymic IL-7 niche in vivo
Nuno L Alves, Odile Richard-Le Goff, Nicholas D Huntington, Ana Patricia Sousa, Vera SG Ribeiro, Allison Bordack, Francina Langa Vives, Lucie Peduto, Ann Chidgey, Ana Cumano, Richard Boyd, Gerard Eberl, James P Di Santo
Proceedings of the National Academy of Sciences | NATL ACAD SCIENCES | Published : 2009
The thymus represents the "cradle" for T cell development, with thymic stroma providing multiple soluble and membrane cues to developing thymocytes. Although IL-7 is recognized as an essential factor for thymopoiesis, the "environmental niche" of thymic IL-7 activity remains poorly characterized in vivo. Using bacterial artificial chromosome transgenic mice in which YFP is under control of IL-7 promoter, we identify a subset of thymic epithelial cells (TECs) that co-express YFP and high levels of Il7 transcripts (IL-7(hi) cells). IL-7(hi) TECs arise during early fetal development, persist throughout life, and co-express homeostatic chemokines (Ccl19, Ccl25, Cxcl12) and cytokines (Il15) that ..View full abstract
We thank S. Lesjean-Pottier for technical support. We thank Dr. Paulo Vieira for helpful discussions and critical reading of the manuscript. This work was funded by Institut Pasteur, INSERM, and the Ligue Nationale Contre le Cancer (Equipe Labellisee). N.L.A. was funded by a long-term fellowship from the European Molecular Biology Organization.