In Vivo Tracking of Dendritic Cell Migration.

Dendritic cells (DCs) in peripheral tissue serve as a sentinel to invasion and maintain tolerance. They ingest and carry antigens to the draining lymph nodes and present antigens to antigen-specific T cells to initiate acquired immune responses. Thus, understanding DC migration from peripheral tissues and function is critical for understanding DCs' roles in immune homeostasis. Here, we introduced the KikGR in vivo photolabeling system, an ideal tool for monitoring precise cellular movements and related functions in vivo under physiological conditions and during various immune responses that occur in pathologic condition. Using a mouse line expressing photoconvertible fluorescent protein KikGR, we can label DCs in peripheral tissues by changing the color of KikGR from green to red after exposure to violet light and accurately track DC migration from each peripheral tissue to its respective draining lymph nodes.