Driving Gene Expression Specifically in Dendritic Cells

Lymphoid dendritic cells (DC) play an important role in the immune system. They are potent inducers of primary T cell responses and play a crucial part as MHC class II+ “interdigitating cells” in the thymus during thymocyte development. Most of our knowledge about DC was obtained using highly invasive and manipulatory experimental protocols. Since the functions of DC after these in vitro manipulations have been reported not to be identical to those of DC in vivo (1), we intended to establish a system that would allow us to investigate DC-function avoiding artificial interferences due to handling. Here we present a transgenic mouse system in which we targeted gene expression specifically to DC. Using the mouse CD11c promoter we expressed MHC class II I-E molecules specifically on DC of all tissues, but not on other cell types.