5. Clear in xylol; mount in balsam.
c. Unna’s Method for Mast and Plasma Cells.
1. Harden in absolute alcohol; imbed; cut.
2. Stain in Unna’s polychrome methylene blue ¼-12 hours.
3. Wash in water.
4. Differentiate in Unna’s glycerin-ether mixture (Grübler) 15 seconds to several minutes.
5. Wash carefully in water.
6. Dehydrate in absolute alcohol; clear in xylol; mount in balsam.
Mast cell granules are red; plasma cell granules blue.
d. Various modifications of the Romanowsky method stain mast- and plasma-cells very well.