The Spleen: A Vital Organ You Need to Understand Now

4. Red Pulp

The spleen contains red pulp that consists of connective tissue -- the cords of Billroth -- and blood vessels with open pores or sinusoids. The red pulp makes up over 75 percent of the spleen and acts as a storage area for monocytes. Billroth’s cords hold the monocytes in clusters. Many other types of cells such as white blood cells, splenic cells, macrophages, and red blood cells. The red pulp macrophages, like all phagocytes, protect the blood by ingesting foreign materials and aged red blood cells.

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