Submitted August 28, 2008
Accepted February 14, 2009
Novel function for interleukin-7 in dendritic cell development
Tobias K. Vogt, Alexander Link, John Perrin, Daniela Finke, and Sanjiv A. Luther*
Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
Developmental Immunology, Department of Biomedicine, University of Basel, Basel, Switzerland
* Corresponding author; email: sanjiv.luther{at}unil.ch.
Interleukin-7 (IL-7) is crucial for the development of T and B lymphocytes from common lymphoid progenitors (CLP) and for the maintenance of mature T lymphocytes. Its in vivo role for dendritic cells (DC) has been poorly defined. Here we investigated whether IL-7 is important for the development or maintenance of different DC types. Bone marrow-derived DCs expressed the IL-7 receptor (IL-7R) and survived significantly longer in the presence of IL-7. Migratory DCs (migDC) isolated from lymph nodes also expressed IL-7R. Surprisingly, IL-7R was not required for their maintenance but indirectly for their development. Conventional DCs (cDC) and plasmacytoid DCs (pDC) resident in lymph nodes and spleen were IL-7R-negative. Using mixed bone marrow chimeras we observed an intrinsic requirement for IL-7R signals in their development. As the number of CLPs but not myeloid progenitors was reduced in the absence of IL-7 signals, we propose that a large fraction of cDCs and pDCs derives from CLPs and shares not only the lymphoid origin but also the IL-7 requirement with lymphocyte precursors.
