 As part of the reticular network, there are follicular dendritic cells in the B cell follicle and fibroblastic reticular cells in the T cell cortex.The reticular network provides structural support and a surface for adhesion of the dendritic cells, macrophages and lymphocytes.It also allows exchange of material with blood through the high endothelial venules and provides the growth and regulatory factors necessary for activation and maturation of immune cells.