Medulla of lymph node
Encyclopedia
The medulla of lymph node, or medullary sinus, is the central portion of the lymph node
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There are two named structures in the medulla:
Lymph node
A lymph node is a small ball or an oval-shaped organ of the immune system, distributed widely throughout the body including the armpit and stomach/gut and linked by lymphatic vessels. Lymph nodes are garrisons of B, T, and other immune cells. Lymph nodes are found all through the body, and act as...
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There are two named structures in the medulla:
- The medullary cords are cords of lymphatic tissue, and include plasma cellPlasma cellPlasma cells, also called plasma B cells, plasmocytes, and effector B cells, are white blood cells which produce large volumes of antibodies. They are transported by the blood plasma and the lymphatic system...
s, macrophages, and B cellB cellB cells are lymphocytes that play a large role in the humoral immune response . The principal functions of B cells are to make antibodies against antigens, perform the role of antigen-presenting cells and eventually develop into memory B cells after activation by antigen interaction...
s - The medullary sinuses (or sinusoids) are vessel-like spaces separating the medullary cords. The Lymph flows into the medullary sinuses from cortical sinuses, and into efferent lymphatic vessels. Medullary sinuses contain histiocyteHistiocyteA histiocyte is a cell that is part of the mononuclear phagocyte system . The mononuclear phagocytic system is part of the organism's immune system...
s (immobile macrophages) and reticular cellReticular cellA reticular cell is a type of fibroblast that synthesises type III collagen and uses it to produce reticular fibers. The cell surrounds the fibers with its cytoplasm, isolating it from other tissue components and cells....
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