Granulocytes are a category of white blood cells, characterised by the fact that all types have differently staining granules in their cytoplasm on light microscopy. They are also called polymorphonuclear leukocytes (PMN or PML) because of the varying shapes of the nucleus, which is usually lobed into three segments. In common parlance, the term polymorphonuclear leukocyte often refers specifically to neutrophil granulocytes, the most abundant of the granulocytes. more...
There are three types of granulocytes:
- Neutrophil granulocytes
- Eosinophil granulocytes
- Basophil granulocytes
Their names are derived from their staining characteristics; for example, the most abundant granulocyte is the neutrophil granulocyte, which has neutrally-staining cytoplasmic granules.
Other white blood cells which are not granulocytes are mainly lymphocytes and monocytes.
Granulocytopenia is an abnormally low concentration granulocytes in the blood. This condition reduces the body's resistance to many infections. Closely related terms include agranulocytosis and neutropenia.
A granuloma is a tumor containing granulocytes, and a "granulomatosis" is a necrotizing granuloma.
Read more at Wikipedia.org