The spleen is the part of the lymphatic system and it plays a vital role in healthy functioning of the immune system. The spleen filters blood and controls the amount of blood in the body. All vertebrate animals have this organ.
Role of the Spleen in the Immune SystemThe spleen consists of two types of tissue that are intermixed: red pulp and white pulp. The red pulp tissue has a role to produce lymphocytes and to destroy deteriorating red blood cells and recycle their hemoglobin. The white pulp is a lymphoid tissue that produces certain immune cells. It also filters blood from foreign matter and germs like bacteria, viruses and parasites. Before a person is born, the spleen produces red blood cells but after birth bone marrow performs this task. Another function of the spleen is to store blood. It acts like reservoir of blood that is supplied in emergency situations like excess loss of blood due to injury or cuts. The spleen stores the platelets and white blood cells. Role of this organ in the immune system is very important since white blood cells in the spleen trap disease-causing agents.
Location of the SpleenThe spleen is strategically positioned in the body. It is located is the upper left part of the abdomen, to the left of the stomach, below the diaphragm. The spleen is an oval shaped organ and it is about the size of a fist. It is approximately 4 inches long and weighs less than ½ lb. During and after digestion, the size of the organ increases. The spleen has gray and purple color. This organ cannot be felt by touch since it is protected by the rib cage unless the spleen becomes abnormally enlarged due to certain health conditions.
The spleen is susceptible to injury due to its location. Spleen injury can result from direct injury caused by an accident. It can also occur due to fracture of the ribs on the left side. In rare cases, the spleen can be injured in contact sports such as hockey and football. If the injury is severe, the spleen may instantaneously rupture and cause internal hemorrhage. It is a serious condition that requires emergency treatment otherwise it can be life threatening. Location of the spleen also makes this organ vulnerable to infections and diseases. This organ can be damaged due to diseases like mononucleosis, leukemia, tuberculosis, hepatitis and sickle cell disease. In case of ruptured spleen or severe damage by certain medical condition, the spleen can be removed. However, people who have their spleen removed are prone to infections and they have to be vaccinated to reduce the risk of infection.