Table 3. Recommended markers to delineate between basophils, eosinophils and mast cells.
| Technique | Cell type | Markers and expected staining reactions with cells |
|||||
|---|---|---|---|---|---|---|---|
| CD34 | BB1 | 2D7 | Tryptase | CD117/KIT | EMBP | ||
| Flow cytometry | |||||||
| Myeloblast | + | n.k. | n.k. | − (+/ − a) | + | n.k. | |
| Basophil | − | n.k. | n.k. | n.k. | − | n.k. | |
| Eosinophil | − | n.k. | n.k. | n.k. | − | n.k. | |
| Mast cell | − | n.k. | n.k. | +a | + | n.k. | |
| Immunohistochemistry | |||||||
| Myeloblast | + | − | − | − (+/ − a) | + | − | |
| Basophil | − | + | + | +/ − b | − | +/ − | |
| Eosinophil | − | + | + | − | − | + | |
| Mast cell | − | +/ − | +/ − | + | + | − | |
Abbreviations: EMBP, eosinophil major basic protein; n.k., not known.
a
In a subset of patients with acute myeloid leukemia, myeloblasts stain positive for tryptase by immunohistochemistry and flow cytometry; and in patients with mastocytosis, tryptase can be detected in mast cells by flow cytometry using a cytoplasmic staining protocol.
b
In chronic myeloid leukemia, immature basophils display substantial amounts of tryptase.