Segregation of B cells and T cells in a lymph node

The schematic diagram illustrates the path by which naive T and B lymphocytes migrate to different areas of a lymph node.  The lymphoyctes enter through an artery and reach an High Endothelial Venule (HEV), shown in cross-section, from where naive lymphocytes are drawn to different areas of the node by chemokines that are produced in these areas and bind selectively to either cell type.  Also shown is the migration of dendritic cells, which pick up antigens from the sites of antigen entry, enter through afferent lymphatic vessels, and migrate to the T cell-rich areas of the node.