Lymphatic System Organs

A part of the immune system, the lymphatic system does work of circulating lymph, a clear liquid in the body; the tissue fluids are drained by lymphatic system. Description of the lymphatic system was first provided by Thomas Bartholin and Olaus Rudbeck. Lymphatic tissues and vessels carry out the circulation of lymph. The flow of lymph through lymphatic system takes place only towards heart. The different organs which together carry out production and circulation of lymphocytes include the spleen, thymus, etc.

Organs of the Lymphatic System

The lymphatic system organs are described one-by-one in this article. Lymph node is an important component of the lymphatic system. Information about this and other organs are presented through following paragraphs.

Lymph Node: The lymph node is an organ of lymphatic system and which is present at different locations in the body. This organ is important from the point of smooth functioning of immune system. The lymph nodes are formed of lymphatic tissues and a fibrous capsule enclose them. Carrying out the filtration of lymph is main function of these nodes. The filtration work involves separation of phagocytes, microorganisms and damaged cells. Production of lymphocytes, antitoxins and antibodies also is an important function of lymph nodes. Lymph nodes are found in the head & neck, thorax arms and lower limbs.

The number of lymph nodes present in our body ranges between 500 and 600. Lymph nodes present in head & neck region are cervical, tonsillar, sub-mandibular and retropharyngeal lymph nodes. The cervical nodes are two in number i.e. anterior and posterior cervical. Sub-mental and Supraclavicular are the two retropharyngeal lymph nodes. Lymph nodes of lungs are subsegmental, lobar, segmental and interlobar; the other lymph node of thoracic region is mediastinal lymph node. Supratrochlear and deltopectoral are superficial lymph nodes of arm. Lateral, pectoral, intermediate, subscapular and subclavicular are the deep lymph glands of arm. Superficial inguinal, popliteal and deep inguinal lymph nodes are located in the lower limbs.

Cisternae Chyli: This organ of the lymphatic system is at the front part of abdominal vertebrae (upper). Cisternae chyli is the organ which receives lymph fluid from abdominal cavity, pelvic cavity and legs. A duct called the thoracic duct emerges from cysternae chyli; it carries out the function of transporting lymph from left side of body. This duct carries lymph through subclavian vein. Lymph from right side of the body is carried by right lymphatic duct through right subclavian vein.

Thymus: This organ is located behind sternum and in front of the heart. Thymus plays an important role in the functioning of immune system. Structure of thymus is characterized by two lobes which have an identical appearance; this organ carries out the production and secretion of thymosins. T-lymphocytes, the important cells of adaptive immune system are controlled by thymosins. Central region of thymus is the medulla, while cortex is present at the periphery. The whole structure is surrounded by a capsule. The development process of T-lymphocyte cells is supported by thymus; this organ provides the development process with an inductive environment.

Spleen: The spleen is a secondary lymphoid organ. It is located in the abdominal cavity just behind stomach and to the left side of body. A collagenous capsule encloses the sac-like structure of spleen. Spleen is normally purple/red in color. The organ turns pink when it is in the process of fighting off infection. Collagenous extensions known as trabeculae are present in the spleen and form a part of support structure of this organ. A network of reticular fibers originate from trabeculae; this network appears more like the plant root system. Reticular cells are present on top of the reticular fibers.

The lymphatic system which protects the body from pathogens is divided into various organs. Explanation of these lymphatic system organs help understand more about their functioning. These organs are important from the point of immune system functioning.