Spleen Function in Immune System

The immune system is the key unit which protects the body against all kinds of diseases and infections. There are various types of immunity; active, passive, cellular, humoral and herd immunity. The immune system in vertebrates is more sophisticated and consists of many types of proteins, cells, organs and tissues. Among these many parts, located in the left upper abdomen, underneath the left rib cage in humans, is an organ known as the spleen. This organ is present virtually in all vertebrate animals.

The spleen in humans is a soft organ and of the size of a fist. It is dark purple in appearance, and 12 cm length, 7 cm height and 4 cm thickness are the average statistics of this organ. The spleen can weigh from 100 to 205 g, depending on the age and health of an adult. Although the spleen is not necessary for human survival, its absence would make us more vulnerable to infections. Now let's come to a broader explanation of spleen function in immune system.

Spleen Function in Humans
Spleen function in immune system is incomplete with its two distinct components; the red pulp and the white pulp. The red pulp is responsible for the filtration function of the spleen and acts as a reservoir for the blood. This filtration process of the red pulp involves removal of old or damaged red blood cells from the circulation. The large number of sinuses and sinusoids filled with blood, which act as a storage, provide the supply of blood in case of any emergency which may cause severe blood loss. The immunological function of spleen in human body is looked after by the white pulp which consists of aggregates of lymphoid tissue. Its main purpose is to mount an immunological response to antigens within the blood and this is what plays a vital role in fighting infections. Precisely, it can be said that spleen function in immune system is to filter the blood, store the blood cells and destroy old blood cells.

Factors Which May Hamper Spleen Function in Immune System
Enlargement of the spleen is one of the most critical spleen problems which may affect the function of this organ in the immune system. Diseases such as mononucleosis, liver cirrhosis, lymphoma, leukemia, and polycythemia vera has spleen enlargement as one of its severe symptoms. Spleen enlargement raises concerns as it takes the risk of developing infections to a higher level. This is due to the fact that when the organ enlarges in its size, it tends to trap more than required red and white blood cells and platelets at an abnormal rate. This causes a lack of the amount of blood cells in the blood stream which are required to protect the body against infections.

This disorder of the spleen is cyclic in nature. The more the organ traps the blood cells, the more it increases in size and eventually it causes major turmoils in the spleen function in immune system. At a severe stage, the spleen may run out of its own blood supply and it may cease to function or die. Another medical disorder known as sickle cell anemia causes the spleen to shrink and become non-functional.

To sum up, apart from giving you a brief idea about the importance of spleen function in immune system, this article about immune system and spleen also briefed you about some of the factors which may disrupt it. Knowing about the different causes and symptoms of any disorder of this vital part of the immune system is as important as being aware of its function. The treatment is centered around addressing the underlying cause of the disorder through non-invasive procedures. In some cases, surgical removal of the spleen (splenectomy) may also be required.