Question of the Day

This is a basophil, typically associated with allergy or parasite infestation. Basophils (BSO), eosinophils (EOS), and neutrophils (PMNs) are the three types of granulocytic white blood cells.

Phagocytosis is an important function of EOS and PMNs but this is not a primary role of BSOs. Granulocytic phagocytes have segmented nuclei and cytoplasmic granules – orange/pink in EOS; purple/dark blue in BSOs; pale pink in PMNs.

The granules of basophils contain many mediators of inflammation and large amounts of histamine. They commonly respond to allergic conditions and parasite infestation, similar to eosinophils.

For more info and images, see the Cornell Clin Path website: Hematology Atlas, and Equine blood cells.

Image courtesy of Guy Waterval.