Development of lymph node circulation and homing mechanisms

The blood vasculature provides both oxygen and nutrients to the high energetic environment of lymphoid tissue and provides a portal for entry of lymphocytes. The vasculature is uniquely different from that found in other organs due to the requirement for efficient recruitment of lymphocytes under non-inflammatory, physiological conditions. It is highly spatially organised, controlling both the site of cellular entry and contributing to the structural organisation of lymphoid tissues. Understanding the mechanisms of blood vasculature development and function is central to understanding how lymphoid tissues form and to understanding mechanisms regulating adaptive immune responses and disease pathologies. Here, we review the development, maintenance and plasticity of lymphoid blood vasculature, as well as the tissue-specific expression patterns of high endothelial venules, which govern lymphocyte trafficking in steady state and during inflammation. © Springer-Verlag Berlin Heidelberg 2011.