Location: wide distribution throughout the body, concentration in axilla, groin, and mesenteries. They are interposed in the pathway of lymphatic vessels.
Function: filtration of the lymph, phagocytosis of particulate material, presentation of antigens to immunocompetent B cells.
Location: the outer portion of the node.
Location: the inner part of the node.
Function: lymph channels, monitoring the lymph as it percolates the sinus.
Composition: the discontinious endothelium. The lumen is span with macrophage processes and reticular fibers surrounded by reticular cell processes.