While it was believed in the Middle Ages that the spleen degrades the black bile produced by the liver - an abundance of black bile was also responsible for the outbreak of leprosy - it is now known that spleen tissue is a filter for blood and pathogens. The spleen leads rather a shadowy existence. Few people know exactly where they are, let alone what they do. It is the filter system of our blood system and an important part of our immune system - and presumably it causes side stabbing.
What does the spleen look like and where is it exactly?
The spleen (synonyms: Splen, Lien) is a relatively small organ - usually you can not feel it from the outside. It is about 11 cm long, 7 cm wide and 4 cm thick and weighs between 150 g and 200 g. It has the shape of a bean and feels soft, its color varies between cherry red and blue violet.
The spleen is located below the diaphragm in the left upper abdomen: it borders there on the stomach, the left kidney and the pancreas, so the pancreas. Through connective tissue ligaments it is connected to the neighboring organs. From the outside, the spleen surrounds a connective tissue capsule (tunica fibrosa) that protects the soft interior.
From here, supporting beams lead inwards, between which the spleen pulp (lat. Pulpa = meat) sits. This pulp is divided into the so-called red pulp (Pulpa rubra) and white pulp (Pulpa alba) - they fulfill different tasks. The names are related to the appearance of the spleen areas: when the spleen is cut open, the red pulp appears as a red tissue in which the white pulp sits as white nodules.
The spleen is supplied with blood via the spleen artery (arteria lienalis), and from the spleen the blood flows via the vena lienalis to the liver. The spleen is well supplied with blood: our complete blood is pumped through it about 500 times a day!
What functions does the spleen have?
The red pulp consists of a well-perfused connective tissue network (Reticulum splenicum), in which old blood cells (erythrocytes) get stuck, which are no longer so elastic and are "caught" by the net - they are then broken down by macrophages. The spleen "recycles" the iron from the hemoglobin (red blood pigment). Even small blood clots and "spent" platelets (platelets) are sorted out in the spleen and broken down.
The white pulp belongs to our immune system. On the one hand, it stores lymphocytes (that is a certain kind of white blood cells), which also partially mature in the spleen. About 30 percent of all white blood cells are stored this way. The lymphocytes react to pathogens such as bacteria, which enter the spleen with the blood, and can thus ward off an infection. If necessary, the lymphocytes stored in the spleen are also released into the blood. In addition, in the white pulp immunoglobulins are formed, which are special antibodies against pathogens.
In addition, the spleen always stores a certain amount of blood, which can be released, for example, during a bleeding in the body or in case of great effort. This probably creates the sideways, which sometimes plagues us during sports.
The spleen in the course of life
In unborn children, the spleen significantly produces the blood cells. This function normally ceases after birth - the bone marrow then takes over the production of blood. However, if blood cell production of the bone marrow is disturbed by a disease (for example, leukemia), the spleen may become active again.
All the tasks performed by the spleen are also taken care of by other organs in the body: the bone marrow produces blood cells and the lymph nodes fight infiltrating pathogens. This makes the spleen dispensable, you can survive without them. However, this may increase the susceptibility of certain pathogens, for example, pneumococcus appear more likely to trigger dangerous meningitis or pneumonia - a vaccine then provides protection.