Basophils are a type of white blood cell, specifically a granulocyte, that plays a role in the immune system. They are a part of the innate immune response and are involved in the body’s defense against parasitic infections and allergic reactions. Basophils are characterized by the presence of large, dark-staining granules in their cytoplasm, which contain substances such as histamine and heparin.
Histamine is released by basophils in response to allergens or injury, causing blood vessels to dilate and become more permeable, which leads to the characteristic symptoms of inflammation, such as redness, swelling, and itching. Heparin is an anticoagulant that helps to prevent blood clotting.
Basophils are produced in the bone marrow and circulate in the bloodstream. They are relatively rare, making up only a small percentage of total white blood cells. However, they are important for mounting immune responses against certain pathogens and for regulating inflammatory reactions.