Macrophages and neutrophils in the White Pulp of the spleen phagocytize old and degenerating RBCs. Lymphatic capillaries are typically lined by endothelium without a basal lamina. Dense lymphatic tissue consists primarily of macrophages, fibroblasts and collagen fibers. The splenic sinuses trap old RBCs and remove HJ bodies. Aggregates of white blood cells surround the incoming arterioles.
Some capillaries are open on one end and release RBCs into the spaces surrounding the blood sinuses.
Macrophages are in abundance surrounding the penicillar arterioles, where old RBCs are phagocytized leaving behind reddish-brown pigment. The marginal zone of the spleen contains blood sinuses that filter antigen for presentation to macrophages and lymphocytes. Hemal nodes do not contain lymphatic vessels. Hemal lymph nodes would be confused with hemorrhagic spleens. The cortex region of the lymph node contains T and B lymphocytes 1.