Eosinophil granulocyte

Eosinophils - short also called eosinophils - are among the leukocytes. They make up about 1-5% of the cells in the differential blood count and are involved in cellular immune defense. Your name they refer the dye eosin, with which they can be stained. Eos ( ancient Greek ) means dawn.

In their interior contain eosinophils vesicles, also called granules, the basic proteins, such as major basic protein and lysosomal hydrolytic enzymes include peroxidase. The content of the granules can be discharged to the environment by exocytosis. Trigger this include antibodies of the IgE class. In addition, they are capable of chemotaxis, ie they can amoeboid toward an attractant substance ( Attractant ) move. In addition to the toxic effects of their granules, eosinophils have the capacity for phagocytosis.

Eosinophils play an important role in defense against parasites. Once the parasite surface is occupied by IgE, eosinophils bind thereto. This serves as a stimulus for the release of the toxic contents of the granules on the surface of the parasite. At the same time, in addition to the damage to the parasites that exozytierten proteins serve as attractants for other eosinophils, so that the defense can be strengthened.

However, eosinophils may also play a role in self-destructive for the organism. In bronchial asthma, for example, the lung epithelium is attacked by the basic ingredients of eosinophils. Triggered eosinophils rare diseases are eosinophils fasciitis and the hypereosinophilic syndrome and eosinophilic esophagitis.

Physiologically, the eosinophils in the lymphocytic - eosinophilic healing phase are propagated. Even with allergies, the number is increased, so that the so-called eosinophilia is an important indicator of the presence of allergy. A reduction in the eosinophil count is called eosinopenia.