Eosinophils are a type of white blood cell that play a crucial role in the immune system. They are part of the innate immune response and their main function is to defend the body against parasitic infections and other foreign substances. Eosinophils are characterized by their large, bi-lobed nucleus and the presence of prominent granules within their cytoplasm, which contain a substance called eosinophilic cationic protein.
These cells are primarily found in tissues throughout the body, including the gastrointestinal tract, respiratory system, and skin. They are attracted to sites of inflammation and infection through a process called chemotaxis, where they release chemical signals to navigate towards the affected area.
Eosinophils are particularly effective against parasites as they release toxic molecules, such as major basic protein and eosinophil peroxidase, that can destroy the parasite's cell membranes. Additionally, they help regulate inflammation and play a role in allergic responses, such as asthma and allergic rhinitis, where they release histamines and other chemical mediators.
Abnormal levels of eosinophils can indicate various health conditions. Eosinophilia, an increase in eosinophil count, may occur in response to allergic reactions, asthma, certain infections, autoimmune diseases, or certain types of cancers. Eosinopenia, a decrease in eosinophil count, can be an indicator of stress, severe infections, or the use of certain medications.
In conclusion, eosinophils are specialized white blood cells that contribute to the body's defense against parasites, participate in allergic reactions, and regulate inflammation.
