Lymphocytes in the white pulp of the spleen (400X)

Thsi image shows details of the white pulp. It consists of lymphoid tissue surrounding central arteries, organized into lymphoid follicles that include a periarteriolar lymphoid sheath (PALS) predominantly made up of T lymphocytes. Surrounding the PALS are germinal centers, which primarily contain B lymphocytes and macrophages. This area plays a crucial role in the immune response by producing lymphocytes and antibodies, with germinal centers serving as sites for B cell proliferation and differentiation.

The histological architecture of the spleen is crucial for its dual role in filtering blood and mounting an immune response. The lymphoid follicles contain proliferating B cells, the PALS is the site of T cell activity, and the marginal zone is key for capturing antigens from the blood.