White pulp

The White Pulp is a part of the spleen that is associated with immune functions. It is named for its white appearance due to the abundance of lymphocytes and macrophages, which are types of white blood cells. The white pulp is surrounded by the red pulp, which is involved in filtering the blood.

Structure

The white pulp is organized around the arterioles, or small arteries, within the spleen. It is composed of lymphoid tissue, which includes lymphocytes and macrophages. These cells are involved in the immune response, including the production of antibodies and the destruction of bacteria and other foreign substances.

The white pulp is divided into two main areas: the periarteriolar lymphoid sheaths (PALS) and the lymphoid follicles. The PALS are areas of T lymphocytes that surround the arterioles, while the lymphoid follicles are areas of B lymphocytes.

Function

The primary function of the white pulp is to mount an immune response. This is done through the production of antibodies by the B lymphocytes and the destruction of foreign substances by the macrophages. The white pulp also plays a role in the activation of T lymphocytes, which are involved in cell-mediated immunity.

In addition to its immune functions, the white pulp also plays a role in filtering the blood. This is done through the removal of old or damaged red blood cells and the recycling of iron.

Clinical significance

Diseases or conditions that affect the spleen, such as splenomegaly or spleen rupture, can also affect the function of the white pulp. In addition, certain infections, such as malaria, can specifically target the white pulp.

See also

• Red pulp
• Lymphoid tissue
• Spleen

References

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  Illustration of the spleen
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  Gray's Anatomy illustration 1191