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Immune and lymphatic systems of the leg and foot

Immune and lymphatic systems of the leg and foot


The primary structures of the lymphatic and immune systems in the lower extremities are the lymph vessels. The large bones of the leg are also important, as these contain bone marrow that produces a large number of lymphocytes.

Immune and lymphatic systems of the arm and hand



The primary structures of the lymphatic and immune systems in the upper extremities are the axillary nodes, which are located just under the armpit (some extend into the chest cavity as well) and the lymph vessels of the arm and hands, which move lymph throughout this region.

The Peyer’s patches

The Peyer’s patches


Peyer’s patches are small masses of lymphatic tissue found throughout the ileum region of the small intestine. Also known as aggregated lymphoid nodules, they form an important part of the immune system by monitoring intestinal bacteria populations and preventing the growth of pathogenic bacteria in the intestines.

The immune and lymphatic systems of the lower torso



The immune and lymphatic systems of the lower torso provides many vital functions to the body, including protection of the body from pathogens and the filtration and transportation of lymph, blood, and lipids. Many different structures, from red bone marrow in bones to the spleen, contribute to these processes.

A wide network of dozens of lymph nodes and countless lymphatic vessels spreads throughout the lower torso. This lymphatic network fulfills the important task of returning the interstitial fluid surrounding the tissues of the legs and lower torso to the blood supply. Interstitial fluid is absorbed by tiny lymphatic capillaries in the tissues, forming the fluid known as lymph. Many lymph nodes in the inguinal and iliac regions connect the lymphatic vessels of these regions and filter lymph as it is carried toward the upper torso. Pathogenic components (such as bacteria or viruses), cellular debris, dead cells, and even cancerous tumor cells are trapped by the lymph nodes and prevented from spreading through the body.

The mediastinal nodes



The mediastinal nodes are a group of lymph nodes located in the thoracic cavity of the body. These nodes play an important role in the filtration of lymph before it is returned to circulatory system.

The axillary nodes



The axillary nodes are a group of lymph nodes located in the axillary (or armpit) region of the body. They perform the vital function of filtration and conduction of lymph from the upper limbs, pectoral region, and upper back.

The axillary lymph nodes are a group of twenty to thirty large lymph nodes located in the deep tissues in and around the armpit. These nodes are arranged into five distinct groups: pectoral (anterior), lateral, subscapular (posterior), central (intermediate), and subclavicular (medial). Each group of lymph nodes receives lymph from a specific region of the body or from another group of lymph nodes.

The immune and lymphatic systems of the upper torso



The upper torso contains many important structures of the lymphatic and immune systems including many lymph nodes, the lymphatic ducts, thymus gland, and red bone marrow. These structures work together to perform the vital functions of producing immune responses to deadly pathogens; producing blood cells; transporting lymph and lipids; and filtering contaminants from lymph.

A vast network of lymph nodes and lymphatic vessels spreads throughout the diverse tissues of the upper torso. This lymphatic network performs the vital task of draining interstitial fluid from the tissues of the thorax and returning it to the blood supply. Many lymphatic vessels also carry lymph to the upper torso from the limbs, abdomen, head and neck.

The palatine tonsils



The palatine tonsils are located at the back of the throat. One tonsil is located on the left side of the throat and the other is located on the right side. The tonsils play a role in protecting the body against respiratory and gastrointestinal infections.

The lingual tonsils



The lingual tonsil is a small mound of lymphatic tissue located at the back of the base of the tongue. Two lingual tonsils are in the mouth, one on each side of the tongue. They are composed of lymphatic tissue that functions to assist the immune system in the production of antibodies in response to invading bacteria or viruses. If the tonsils are repeatedly swollen or infected over an extended period of time, they may need to be removed.

The cervical nodes



The cervical nodes are one of the six major locations of lymph nodes. They are grouped along the lower border of the jaw, in front of and behind the ears, and deep in the neck along the larger blood vessels. They drain the skin of the scalp, face, tissues of the nasal cavity, and the pharynx. All lymph nodes have the primary function of the production of lymphocytes, which help defend the body against microorganisms and against harmful foreign particles and debris from lymph before it is returned to the blood stream.