Effector T-cell responses in non-lymphoid tissues: insights from in vivo imaging

T-cell responses are initiated within secondary lymphoid organs, and effector T-cells are released into the circulation where they home to inflamed tissues and mediate protective immune responses. Within non-lymphoid tissues, the types of cellular interactions and the dynamics that lead to clearance of infections are still relatively poorly understood. Here I review how imaging of effector T-cells within tissues has contributed to our understanding of immune responses, and examine some of the remaining questions that may benefit from in vivo imaging to reveal the intricacies of how immune cells function. A detailed understanding of the dynamics of T-cell responses within non-lymphoid tissues is important for the rational design of targeted therapies that influence key steps in disease progression. Immunology and Cell Biology (2013) 91, 290-296; doi:10.1038/icb.2012.75; published online 8 January 2013