Through the Microscope: Blood Cells - Life's Blood

Eosinophil

Eosinophils are the mature granulocytes that respond to parasitic infections and allergic conditions. Eosinophils comprise about 1 to 4% of the peripheral leukocytes. They are usually 9 to 15 µm in diameter. Granules stain a bright reddish-orange with Wright's or Giemsa stains. The nucleus contains one to three lobes. The chromatin pattern is coarse and clumped. The cytoplasm is abundant with a full complement of bright reddish-orange specific granules.