Dendritic cell migration to peripheral lymph nodes.

Dendritic cells are potent antigen-presenting cells endowed with the unique ability to prime T-cell responses. To present foreign antigens to na ive T cells, dendritic cells must migrate from inflamed or injured peripheral tissues to the closest draining lymph nodes through afferent lymphatic vessels. In addition, conventional dendritic cells, plasmacytoid dendritic cells and monocytes enter lymph nodes from blood crossing high endothelial venules. The selective migration of dendritic cells and their residence in non lymphoid as well as in lymphoid organs are tightly regulated events, whose molecular control is being unraveled rapidly. In this chapter, we review key aspects of what is known about dendritic cell traffic to peripheral nodes from tissues, in particular skin, and from blood. A better understanding of the regulation of dendritic cell migration for optimal priming of T-cell responses is essential for future advances in manipulating dendritic cell traffic as a means to improve immune responses in clinical settings.