July 1, 2023
Basophils are a type of white blood cell (WBC) that play a role in the body’s immune response. Basophils are similar in appearance to mast cells and are known for their large, dark-staining granules in the cytoplasm (body of the cell). Basophils are relatively rare, making up between 0.5% to 1.0% of circulating white blood cells.
Basophils are part of the innate immune system and play a role in the body’s defense against parasitic infections and allergic reactions. They release histamine, heparin, and other chemical mediators in response to certain stimuli, such as allergens, that can trigger an immune response.
Histamine is a potent vasodilator that increases blood flow and permeability in the surrounding tissues, allowing immune cells and other molecules to access the site of infection or inflammation. Heparin is an anticoagulant that prevents blood clots from forming at the site of inflammation.
Basophils also produce cytokines, such as interleukin-4 (IL-4), which help to activate and recruit other immune cells, such as T cells, B cells, and eosinophils, to the site of infection or inflammation.
After being produced in the bone marrow, basophils travel in the blood to sites of injury or infection. Under normal conditions, only a small number of basophils are usually found in the blood.
Basopenia means that your body is not producing enough basophils. Conditions associated with basopenia include infections, allergic reactions, and hyperthyroidism (too much thyroid hormone).
Basophilia means that you have too many basophils in your blood. Conditions associated with basophilia include leukemia (a cancer of the blood), polycythemia vera, myelofibrosis, inflammatory bowel disease (ulcerative colitis or Crohn’s disease), autoimmune disease, or hypothyroidism (too little thyroid hormone).