How do the red pulp and white pulp of the spleen differ?

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Diagram of the human lymphatic system highlighting lymphatic vessels and major lymphoid organs, including lymph nodes, adenoids, tonsils, thymus gland, spleen, appendix, bone marrow, and ducts. — lymphatic system The human lymphatic system, showing the lymphatic vessels and lymphoid organs.

The spleen contains two distinct types of tissue, red pulp and white pulp, which are intermingled throughout the organ rather than separated into distinct regions.1

White Pulp: This is lymphoid tissue that typically surrounds splenic blood vessels. It contains lymphocytes, plasma cells, and lymphatic nodules (follicles). Its germinal centres serve as sites for lymphocyte production, and it plays a key role in initiating immune reactions against antigens in the bloodstream.1
Red Pulp: This consists of a network of splenic cords and sinusoids filled with blood. It is the primary site for blood filtration and the destruction of aged red blood cells. Additionally, the red pulp acts as a reservoir for monocytes and other phagocytic cells that help regulate inflammation and facilitate tissue healing following injury.1

Both types of pulp contain macrophages that remove foreign material from the blood.1