Moving to the suburbs: T-cell positioning within lymph nodes during activation and memory.

Lymph nodes are highly organized secondary lymphoid structures crucial for the initiation of immune responses. Naive T cells are strategically located within lymph nodes to optimize their encounter with antigen-loaded dendritic cells. Recent advances in 3D lymph node imaging and tissue reconstruction along with methods for the detection of chemokine expression and gradients have highlighted how T cells position themselves during activation and memory responses. This article covers new insights into the guidance mechanisms that co-ordinate T-cell responses within draining lymph nodes. Furthering our understanding of how these pathways are regulated and promoted will lead to the exploitation of T-cell positioning to further strategize vaccine design.